OEM Brake upgrades

[Canadian818]

While I had my heart set on wilwoods, I've decided to use the OEM brakes until such time that I NEED more brakes or I have money to burn. Perhaps those members who have been racing subarus can chime in.

SS lines are a must IMO
Any aftermarket slotted rotors?
What fluid?
What pads for street/race? What about swapping pads for the track?

I'll do some research tonight, but wanted to post up before I forgot :)

[StatGSR]

What factory brakes are your running? i would expect that with the right pad combo, you will never need more brake than the factory units could supply.

Pro Tip, don't bother with slotted rotors, plain rotors work just fine and wont wear pads as quickly. I would recommend Centric rotors with the black coating on the hats.
Fluid, I would say ATE super blue, but that has been discontinued, so i would go with ATE Type 200 which is the same fluid, just a normal gold color.
Almost any good track pad will be a bit of a compromise on the street, nothing wrong with swapping pads for a track day. Some pads that "might" work well enough on the track and still work on the street would be Hawk HP+ or Axxis Ultimate. Both have a fairly high heat threshold but will both dust a bit more than desirable on the street. Pads much more aggressive than those will be a little crappy on the street and will dust like crazy. If you were to do street pads/track pads, i would recommend Hawk HPS for the street and Hawk Blue for the track, Blues are kind of a entry level track pad, but they are at a good price point and are fantastic pad for HPDEs, they are pretty hard too cook and i have been running the same front set for 3 years on my integra, you probably wouldnt want to run Blues in the back though, might have too much friction.

[Santiago]

I'd second what StatGSR said, so mostly I'll just offer some personal experience.

I run a fairly heavy Mustang that I've tracked for about 6 years. For the first few years I used the OEM brakes with nothing other than a pad change. I used to use dedicated rotors (OEM take-offs, plain rotors) that I'd swap out along with the pads. Later I graduated to just doing pad swaps once I switched over all my pads (street/track) to the same manufacturer (Carbotech - they don't play well with other compounds, so you either have a dedicated rotor/pad set or you have street pads and track pads from them). Hawks are more forgiving of interfacing with different compounds, since they're more abrasive and sort of "self-clean" the rotor face as they begin to bed.

That combination worked extremely well. Really, for most HPDE duty it was very adequate with nothing more than a good brake cooling set up (mandatory), upgraded fluid (mandatory), and appropriate track-only pads (highly recommended). For fluid I use Motul RBF600 (Boiling point Dry: 594F (312C), Wet: 421F (216C)). When choosing a brake fluid, don't just look at the dry boiling point, look at the wet as well, since this is closer to what you'll have after a while if you're not religious about bleeding the brakes after each event.

I run w/other guys who have the same S197 chassis I do, and they too got along very well for a long time with the stock 12.5" OEM brakes up front and 11" in back. We've since upgraded to BBK systems, but for specific reasons. That is, we made the change to address specific things we increasingly felt needed attention. These were:

1. Thermal capacity of the rotor: the need was to have a larger mass (14" rotors) to better deal with heat over longer periods of use. The larger rotors are more expensive, but we're replacing them with far less frequency. The OEM rotors crack in a shorter period of time. I get a full season (or touch more) out of my rotors now, whereas I would go through 3 sets a season using the OEM ones.

2. Rigidity/durability of the caliper: one of my buddies was going through a set of front calipers a season due to caliper spreading. You could see the pads taper from outer edge to inner edge as they'd begin to lose their parallelism. The rear calipers still do this, but far-far less frequently than the fronts ever did.

Notice there is no mention of "stopping quicker or sooner," since that is best accomplished with better tires. We switched because we were simply going through equipment at an increasing rate and it became tedious. Upgrading made sense in the context of frequent and very hard use. BTW, both of us are NASA instructors, so we're doing a lot of events, giving a lot of instructional rides on top of our own runs.

I should end by saying that we did get "better braking performance" in the upgrade, but not in terms of "stopping distance." We got better pedal feel, better modulation (pad selection has a lot to do with this too), and better consistency (my buddy does enduros, so the poor things out there for 4 hours at a time). Pad choice also gives my set up better initial bite, but that's something you can get out of the pads alone.

Hope that helps.

Best,
-j

[Rasmus]

SS lines are a must IMO
No they're not. They don't increase pedal feel at all. 100% of the pedal feel increase guys report when swapping to SS lines is due to flushing the fluid. With all the tiny air bubbles and water flushed the pedal feels much better. I know becuase I did a flush then two weeks later swapped to SS lines. No increase in pedal "feel" from the lines. Difference felt after flushing fluid. Don't waste your money on SS lines.


Any aftermarket slotted rotors?
No holes. No slots. The most extreme road race rotors are blank face. Blank face only. Centric Premiums are nice. I've also used Autozone brand blank face for track days. They're inexpensive at $20-$40 per, and absorb heat really well. Track days eat rotors for breakfast. You'll be going though a lot of them if you do a lot of track days. So much easier to eat $60 for a new set of two than $460.


What fluid?
Dot 5. I use Gunk Brand. It's a pretty color too.


What pads for street/race? What about swapping pads for the track?
There is no such thing as street/race pads. Anything that advertizes that's it is a street/race pad is lying to you and wouldn't do both well. It's marketing.


You're gonna want two full sets of rotors and pads. Yes two.

One set will only be for track days. Because if you do it right the pads are bedded to the rotors and you don't want to **** that up one you get it done. They become a set. These pads won't do well when cold. In fact, you might think they're not working right at first application. But once they get up to temp you'll get bruises on your collarbones because they will just keep braking 'til the end of the session. That is, you'll never experience fade during a session. Street/race pads will fade. And if they don't you're not driving hard enough.

Your second set will be your everyday/cruise pads and rotors. Get the lowest dust pad there is and bed them to a set of rotors.

[Rasmus]

The best "Poor Man's Big Brake Kit" in my opinion for the front of a WRX is

https://sphotos-a.xx.fbcdn.net/hphotos-prn1/67375_339138542853174_340617949_n.jpg
Z32 Nissan Aluminum calipers, with KNS Brakes Z32 to WRX adapter. Legacy GT/B9 Tribeca rotor.

KNS sells the whole set up, less pads, for $400. (http://www.knsbrakes.com/c/item/53589_Subaru+Z32+Front+Brakes) That's a deal!

[Canadian818]

Wow! Thanks everyone for the info/advice. I wasn't expecting such detail.

I'm using 07rs brakes, 11" front, not sure the rear or piston #'s, I'll check when I get home. Cheap rotors and good pads it is! I'll get some fluid, not sure what brand I can readily get locally, but when I do I'll post. I wasn't sure if seperate rotors were necessary, but it makes sense.

I hadn't thought about the fluid being the difference when installing ss lines in my 240sx, but it makes sense. I still want them, but more for bling than anything I guess. If frequent fluid changes are in my future, I should invest in Mikes res-relocation kit.

Also, I put this in the wrong section, could an admin please move it.

Thanks, Adam

[Rasmus]

Notice there is no mention of "stopping quicker or sooner," since that is best accomplished with better tires. We switched because we were simply going through equipment at an increasing rate and it became tedious.

A big hearty, "Hear! Hear!" for the above statement.

Tire compound, track/surface conditions, and vehicle weight are what determine stopping distance.

Rotors and pads determine how many times back to back to back you can 10/10ths brake until the system overheats and you drive into the sand because the pad starts smearing.

[Wayne Presley]

A set of Hawk HP+ or DTC30's do wonders for feel and power of the brakes. I'd replace the lines with SS because they do feel better and reusing the stock lines to save $125 seems foolish compared to a line failure...

[Xusia]

I bought a set of SS brake lines mostly for the looks, but the enhanced reliability and potential improvement in feel certainly won't hurt.

[flynntuna]

IMHO since your their with easy access, rebuilding the calipers and such, adding SS lines for me is just a " might as well" item.

[Oppenheimer]

Back in the day switching to SS lines made a huge difference in pedal feel, and not just because of the bleed necessitated by changing the lines. I suspect new school cars this is just no longer the case. That the standard rubber lines used today don't have the issues the rubber lines of old did, so it no longer makes a noticible difference. But of course race/track cars still use them for the safety aspect, so guys see them on these cars and think they still have a performance benefit.

[Racebrewer]

Hi Rasmus,

Anything similar for the rear?

John


The best "Poor Man's Big Brake Kit" in my opinion for the front of a WRX is

https://sphotos-a.xx.fbcdn.net/hphotos-prn1/67375_339138542853174_340617949_n.jpg
Z32 Nissan Aluminum calipers, with KNS Brakes Z32 to WRX adapter. Legacy GT/B9 Tribeca rotor.

KNS sells the whole set up, less pads, for $400. (http://www.knsbrakes.com/c/item/53589_Subaru+Z32+Front+Brakes) That's a deal!

[longislandwrx]

If you want something cheap for the rear just do an H6 upgrade. a 1.1" larger rotor and you can do it for about $120 if you get good deals.

That with the right pads will make a SUBSTANTIAL difference. The H6 upgrade has been talked about several times on this board

[Rasmus]

Anything similar for the rear?


H6 upgrade. a 1.1" larger rotor and you can do it for about $120 if you get good deals. That with the right pads will make a SUBSTANTIAL difference.

What LongIsland wrote. The H6 upgrade. A Good "Poor Man's Big Rear Brake Kit".

http://i162.photobucket.com/albums/t278/RasmusHansen/SubaruParts/IMG_2994.jpg
That red brake adapter above is from the (H6 Legacy's? ) Subaru Catalog. It essentially spaces out the caliper.

http://i162.photobucket.com/albums/t278/RasmusHansen/SubaruParts/IMG_2997.jpg
http://i162.photobucket.com/albums/t278/RasmusHansen/SubaruParts/IMG_2996.jpg
Then you just run your stock caliper on the larger H6 rotor. Parking brake works and everything.

[Rasmus]

And if your still generating too much heat with the z32 Poor Man's Big Brake Kit because you're running some seriously sticky racing slicks. You need water injection.

http://i220.photobucket.com/albums/dd209/sivadleoj/P1010057.jpg
The above is JDWhiteWrx set up on his WRX over on Nabisco. It's just like the V8 Supercars from Aussyland. Just a nice fine mist of water and you'll be able dissipate all the heat you could ever possibly generate at a track day. I'd guess you tie the water misting into the brake light on a delayed relay system. For example the mist would start 1 - 2 seconds after you hit the brakes and would stop 3-4 seconds after you release the brakes.

Just think how cool that'd look with clouds of puffy white steam coming out your front wheels after a hard braking zone.

[Rasmus]

I'm still of the opinion that the z32 conversion is the best "Poor Man's Big Brake Kit" but if $400 is still too much for you there's

http://i162.photobucket.com/albums/t278/RasmusHansen/SubaruParts/IMG_3462.jpg
the Legacy GT brake conversion for the WRX

http://i162.photobucket.com/albums/t278/RasmusHansen/SubaruParts/IMG_4970.jpg
It uses the same rotors as the z32 "Poor Man's Big Brake Kit" but Legacy GT calipers instead. It's a good compromise. You're not having to source the spacer bracket or the aluminum z32 caliper so you save some coin. But you make up for it by the mass of the Leggy's cast iron calipers. It's heavy. The worst kind of heavy. Un-sprung heavy. The above is what it would like like under a 17 inch wheel.

http://www.lotustalk.com/gallery/files/15813-02_wrx_4pot_brakes.jpg
The above is the stock rotor under a 17 inch wheel. You can easily see the size difference.

Poor Man's Big Brake Kits
Best: z32 caliper conversion on Legacy GT rotors
Good: Legacy GT calipers on Legacy GT rotors

[KNS Brakes]

The best "Poor Man's Big Brake Kit" in my opinion for the front of a WRX is

https://sphotos-a.xx.fbcdn.net/hphotos-prn1/67375_339138542853174_340617949_n.jpg
Z32 Nissan Aluminum calipers, with KNS Brakes Z32 to WRX adapter. Legacy GT/B9 Tribeca rotor.

KNS sells the whole set up, less pads, for $400. (http://www.knsbrakes.com/c/item/53589_Subaru+Z32+Front+Brakes) That's a deal!

Wow!

Our little brake kit has made the rounds!

-Ken

[Rasmus]

I touched the internet's NO NO place and hotlinked an image right from another website. :o At least I provided a link to the commercial site hosting the image. :rolleyes:

Or maaaaybe I did a Beetlejuice and said KNS three times.

[Canadian818]

Thanks Rasmus!

I've done a little reading, and I think this is the way to go. Can you confirm that the rear calliper brackets and both front/rear rotors come from 05-09 LGT's? Will subaru brake lines fit the Nissan calliper? And do I just cut the lip off my dust shields? (Painting and installing spindles this weekend)

[StatGSR]

Thanks Rasmus!

I've done a little reading, and I think this is the way to go. Can you confirm that the rear calliper brackets and both front/rear rotors come from 05-09 LGT's? Will subaru brake lines fit the Nissan calliper? And do I just cut the lip off my dust shields? (Painting and installing spindles this weekend)


pretty sure the "H6" rear upgrade uses 00-03 legacy rotors

http://forums.nasioc.com/forums/showthread.php?s=&threadid=522006
https://www.flatironstuning.com/p-1827-legacy-h6-rear-brake-upgrade-for-02-05-wrx.aspx

may want to verify rear calipers/brakets if you plan on using the RS calipers.

[Rasmus]

What StatGSR wrote.

The Poor Man's Big Brake Kit is a Frankenstein Monster. It works when you finally source everything, but you'll be going though a few graves looking for the right parts.

Just don't get anything labeled "Abby Normal".

[Scargo]

Wow!

Our little brake kit has made the rounds!

-Ken As do you! Have been thinking about you and my Stoptechs... I couldn't be happier with my Trophies on the STi. Now that I am getting an 818R I wonder what KNS recommends? I am going to go with a modified STi rear upright. Is that the same as what's on a WRX as far as how the caliper brackets fit?

Everyone: I wonder why nobody is mentioning the Brembos from an STi? As above, do they not fit a WRX rear upright? Are they rare as hen's teeth?
It's OK and fine by me that the discussion seems focused on "economical" or "bang for the buck", but it also is "a compromise". Several are talking "track" and some have the experience so how about some time and energy towards that aspect?
As an example, why not talk about the next level up, which is much lighter floating rotors? I've really liked the Gyrodisc rotors on the back of my STi with the stock Brembos. I'm at a bit of a loss with GD's, but it was easy to drill out the spot-welds on my GR backing plates and get rid of them to make things a bit cooler back there, not to mention the weight loss.

[StatGSR]

I would say we are not talking about the brembos because that was not in the interest of this thread, everyone knows you can spend 3 grand and get "better" brakes, less people know that you can spend $400-$800 on the right pads/rotors/calipers and get more braking power than you will ever need.... This has always been a major frustration for me with the subaru community. They rather buy larger more expensive brake setups with fancy calipers and continue to run crappy pads and talk about how awesome they are. My track integra runs factory rear 10 inch solid rotors with Axis ultimate pads and front 11" rotors upgrade with Integra Type R/Accord single piston calipers with hawk blue pads, I can easily out brake my tires and can slow down faster than most cars on the track, and its still just a $400-500 dollar setup (including all rotors and calipers). It is extremely cheap to maintain, lasts dozens of track days, and this is a car that is a good 600-700 lbs more than an a 818.

[Rasmus]

Once again, ditto StatGSR.

OEM Brembo's are great if you can find them and you want to pay for them. They are not inexpensive. Nothing wrong at all with them. Great brake setup with the right pads.

[Wayne Presley]

I spent 4 days in the prototypes at the track with stock rotors/calipers with upgraded pads (Hawk DTC-60) and was able to lock the wheels at will. I don't see the real need for any street 818 to go to the big brakes kits unless you just want the look in the wheel.

[metalmaker12]

Rebuilt 4pots/2pots for the street and track for me.

[FFRSpec72]

I'm going cheap, getting the 4 piston 12" Willwoods in black, this way I'm under $2000. In my challenge car which is about 650lbs heaver I use the Cobra 2 piston 13" front rotor and the GT 1 piston 11" rear rotors and no issues at all ever and use Carbotech pads, which I will run on the Willwoods also.

I also noticed that places like JEGS are cheaper and don't charge for shipping so you can save another ~$280 going this route and not ordering as part of the kit. That more than pays for my radiator. FFR does not offer just the slotted version and that is all I was looking for as I had my issues with frilled rotors on the track and will stick with just slotted.

[KNS Brakes]

As do you! Have been thinking about you and my Stoptechs... I couldn't be happier with my Trophies on the STi. Now that I am getting an 818R I wonder what KNS recommends? I am going to go with a modified STi rear upright. Is that the same as what's on a WRX as far as how the caliper brackets fit?

Everyone: I wonder why nobody is mentioning the Brembos from an STi? As above, do they not fit a WRX rear upright? Are they rare as hen's teeth?
It's OK and fine by me that the discussion seems focused on "economical" or "bang for the buck", but it also is "a compromise". Several are talking "track" and some have the experience so how about some time and energy towards that aspect?
As an example, why not talk about the next level up, which is much lighter floating rotors? I've really liked the Gyrodisc rotors on the back of my STi with the stock Brembos. I'm at a bit of a loss with GD's, but it was easy to drill out the spot-welds on my GR backing plates and get rid of them to make things a bit cooler back there, not to mention the weight loss.

To put Brembo's on a WRX hub you need a bracket and some way to deal w/ the difference in park brake if you want it to work.

http://www.knsbrakes.com/c/kns-bracket shows a few of the options in that regard.

If it were a track car I would want the bolt in front bearing and the 06-07 WRX rear knuckle so I can mount the rear Subaru 2 pot directly.

I would be Subaru's 4/2 piston setup would do pretty well and certainly would be a good start for any car. Those brakes have stood the test of time on many Subaru's and are still pretty good. They were pretty good on the WRX until I got pretty fast on track w/ some sub 200 TW tire. Then it started eating front pads/rotors.

I would think an adjustable prop valve is all but necessary.

[Ravendas]

No they're not. They don't increase pedal feel at all. 100% of the pedal feel increase guys report when swapping to SS lines is due to flushing the fluid. With all the tiny air bubbles and water flushed the pedal feels much better. I know becuase I did a flush then two weeks later swapped to SS lines. No increase in pedal "feel" from the lines. Difference felt after flushing fluid. Don't waste your money on SS lines.

I gotta disagree. I changed to SS lines from OEM a couple of years ago and it made a huge difference! Of course I went from 8 year old leaking hard-as-a-rock rubber lines to SS.


;-)

[longislandwrx]

Once again, ditto StatGSR.

OEM Brembo's are great if you can find them and you want to pay for them. They are not inexpensive. Nothing wrong at all with them. Great brake setup with the right pads.

Also, in terms of upgraded brakes, Brembos also weigh a ton.... literally all four on a scale weigh 2000lbs. If you got a crazy deal on a set of 04 brembos, it might be worth it but otherwise its a lot of cash, and there's easier/better/lighter ways to do it.

[STiPWRD]

I bought a set of V7 JDM Brembos with rotors, pads, and spindles for my 818S. Spent $1000 for everything and total weight was 194 lbs (they included the rear trailing arms but I will be using aftermarket ones). The brembos are probably overkill but I got them for looks as well. Buying them with the spindles solves the rear caliper bracket problem and I'll probably sell the front spindles since they are the same as the ones I already have.

On a side note, I've also used the Axxis Ultimate pads on my wrx and certainly noticed a difference but they do get very dusty.

[Rasmus]

I gotta disagree. I changed to SS lines from OEM a couple of years ago and it made a huge difference! Of course I went from 8 year old leaking hard-as-a-rock rubber lines to SS.

How many times did you flush the fluid in your 8 year old OEM lines before swapping to SS lines? How close in time was your last fluid flush on the OEM setup before your swap to SS? I reiterate: "100% of the pedal feel increase guys report when swapping to SS lines is due to flushing the fluid."

It's fine if you want SS for the look or abrasion resistance. But to swap for "pedal feel" is just falling prey to marketing.

[Scargo]

... Brembos also weigh a ton.... literally all four on a scale weigh 2000lbs. ... Is that with the 818 attached to the brakes plus hyperbole? Or is it with your thumb on the scale?
Front STI Brembo calipers (04-08) fit 06-07 WRX front uprights. The brake caliper bolts need to correspond to the MY Brembo caliper.
I did not think of my front '08 Brembos as being that heavy.

[longislandwrx]

LOL I may have been leaning on the scale a little but the rotors are heavy and the calipers aren't exactly featherweights... aluminum hats save lbs but that's more $$$ a set of gyrodiscs are going to set you back $1000

[StatGSR]

^ to be fair, some amount of weight is actually a good thing for brakes, helps resist heat build up and boiling brake fluid.

[Scargo]

High performance two-piece rotors weight far less and perform far better at removing heat. All that iron mass is not required to keep things cool.
The weight, the rotating mass and unsprung weight is huge for some of us racers. And we must deal with the heat.
Yes, it cost money to correct it.

For street cars, if you don't address it, and then occasionally drive the car aggressively, the brakes get too hot, then need better, more expensive pads and fluids. Regardless, the massive stock rotors are harder to stop rolling and perform rather inefficiently. Hurts acceleration and braking performance, hurts gas mileage and is harder on the suspension components and tires. The saving money logic is kinda counterproductive to me.
If you don't upgrade the rotors you can still add Ti backing plates and do some simple air ducting-air deflecting to the brakes.

[StatGSR]

I already said that we all know you can blow a huge chunk of change on on expensive rotors and brakes and they are better... in theory. But in reality, your talk of better acceleration, braking performance, and fuel mileage are a huge stretch for your average HPDE driver. If your going into competitive racing then yes, ever little ounce helps, but your average track day enthusiast can gain seconds per lap just by spending more time behind the wheel, not because of how much money he spend on his brake setup all they need is a brake setup that performs well consistently. Dropping 5lbs from each corner of the car will be completely unnoticed by almost every car enthusiast.

[Scargo]

My point really is, it goes beyond performance track driving and racing. I mean, why are there BMWs for the masses? How many ever see the track? Or an STi with its lighter wheels and better brakes than a WRX. People do notice. We are dealing with a sports car, kit car, not a family WRX sedan anymore.
Perhaps it's not apples to apples, because there's consumables involved, but why do people spend extra money for "high efficiency" appliances? It brings down their utility bills and pays off in the long-run.

With wheels and brakes for my '08 STi (with already lighter BBS wheels) I think I shaved, or lopped off, about 15 pounds on each front suspension. That's 30 pounds of unsprung weight on the front... Less weight savings in the rear.
Girodisc 2-pc fronts are $700 and 10 pounds less than a stock rotor. DBA 5000's 2-pc rotors are much cheaper and save six pounds each.

[flynntuna]

Could it be for the same reason people buy trucks and suv's with 4wd? 90% of them never see dirt.

[StatGSR]

My point really is, it goes beyond performance track driving and racing. I mean, why are there BMWs for the masses? How many ever see the track? Or an STi with its lighter wheels and better brakes than a WRX. People do notice. We are dealing with a sports car, kit car, not a family WRX sedan anymore.
Perhaps it's not apples to apples, because there's consumables involved, but why do people spend extra money for "high efficiency" appliances? It brings down their utility bills and pays off in the long-run.

With wheels and brakes for my '08 STi (with already lighter BBS wheels) I think I shaved, or lopped off, about 15 pounds on each front suspension. That's 30 pounds of unsprung weight on the front... Less weight savings in the rear.
Girodisc 2-pc fronts are $700 and 10 pounds less than a stock rotor. DBA 5000's 2-pc rotors are much cheaper and save six pounds each.

I'm guna keep beating this dead horse since that's my style.

Not sure what point your trying to make, BMWs are not all that fancy, they are comfy taxi's and commuters for the rest of the world, only the US has a glorified opinion of them, and dont have anything special in the way of brakes outside of "M" cars. Yes the STI has larger (and heavier) brakes than the WRX, bigger brakes and ligher wheels are to be expected of the top performance model from any car manufacturer. brakes torque and feel are improved by the larger rotor size and the increased number of pistons. High efficiency appliances? yea cause a brake job is cheaper on an STI because its more efficient? pretty sure its the opposite.

Again, yes you can shed unsprung weight (and doing so is never bad), but can average people even notice it? no your average guy cannot, they will also see no real improvement in braking performance, acceleration, or MPGs. A change in tire diameter by half an inch will have a larger impact on all of those things.

As noted, this thread is about OEM brake options and how much braking power is needed, not about how much my money can be blown for infinitesimal performance increases. No mater how you slice it we are taking a braking setup designed for a car that was 1000lbs heavier, the increase in braking performance already exists.

[Scargo]

Just a reminder fellas, the title of this thread is "OEM Brake upgrades". Perhaps we should start another thread to discuss brake setups outside of that scope? Carbon-carbon rotors: GO!
I am talking about upgrades to OEM brakes.:rolleyes:

[longislandwrx]

also, if you wanted to take your z32 brakes to the next level, order them without the rotors, (saving $100)
and get yourself some DBA 5000 series rotors with aluminum hats for $600

[Scargo]

also, if you wanted to take your z32 brakes to the next level, order them without the rotors, (saving $100)
and get yourself some DBA 5000 series rotors with aluminum hats for $600
OR... even lighter Girodisc A1-007 for $710 delivered from Amazon.

[Santiago]

Do they offer hats and friction rings separate for either Girodiscs or DBAs? I'm ok w/a $600-$700 entry fee, but only if I can get replacement rings for less. Eventually you have to replace the hats as well, but they'll last many times longer than the rings, and this brings the cost of running these down considerably.

On my Mustang I have 2-pc rotors (14" front) that I can source for $800/pr. Ouch. BUT, I can get replacement rings for around $200/ea., so that's half the cost per set than getting the whole assembly. I do have two sets of hats, but that's just to allow me assembly time in the garage rather than doing it track-side when the rings are done. Along with the longer life these have given me in general, the added expense isn't as bad as it sounds and they are much lighter than their solid counterparts.

Best,
-j

EDIT: Ok, I see the friction rings now (in the neighborhood of $450/set for front & $350/set for rears), how about hats? I guess you could go w/2 full sets and have the extra hats once both sets of friction rings have been used up. That's actually how I got my two sets of hats for the Mustang - it was cheaper that way.

[Scargo]

About $360 for Girodisc replacement rings and hardware. DBAs you can get but there was a design change about 1-1/2 to 2 years ago that caused some grief and uncertainty about getting them for older hats.
I have several sets of two-piece rotors, but they are for the GR STi. That's how I know about weight differences.

[Rasmus]

Thought I'd bump this thread for fellas that may not have seen it.

[CanadianYank]

Thought I'd bump this thread for fellas that may not have seen it.

Thanks Rasmus, great info its bookmarked...

Frank

[Gary Livingston]

Here's a challenge. . . and seemingly (but not really) stupid question. What would be the lightest, smallest barely legal brakes set up . . . assuming no real need for actual braking . . and no issues with heat? I just want something to pass inspection and hold the car still when stopped. No stopping friction required.
Will aluminum rear calipers fit on the front? What are the smallest, lightest rotors available. I want to loose the un-sprung weight as much as possible. I think there are aluminum rotors for drag racers (illegal I think for the road) but there are aluminum rotors with steel inserts . . probably ridiculous expensive. I don't what to get into coating aluminum. . . I just want something light and legal . . . stopping capability not important. Electric drive uses regenerative braking so, no need for these to do much.

[Bob_n_Cincy]

Here's a challenge. . . and seemingly (but not really) stupid question. What would be the lightest, smallest barely legal brakes set up . . . assuming no real need for actual braking . . and no issues with heat? I just want something to pass inspection and hold the car still when stopped. No stopping friction required.
Will aluminum rear calipers fit on the front? What are the smallest, lightest rotors available. I want to loose the un-sprung weight as much as possible. I think there are aluminum rotors for drag racers (illegal I think for the road) but there are aluminum rotors with steel inserts . . probably ridiculous expensive. I don't what to get into coating aluminum. . . I just want something light and legal . . . stopping capability not important. Electric drive uses regenerative braking so, no need for these to do much.

Hey Gary
First I'll tell you that I have been involved in building EVs for 20 years.
I agree that with regen you don't have to worry about brake heat.
I totally disagree with brakes that have no stopping function .
Two Words "PANIC STOP"
Brakes can typically apply 4 to 6 time torque to wheel than motor controller can.
On the 818 you would only have rear wheel regen braking. Standard brakes use all four wheels.
I would not trust electronics in a panic stop. A high current panic stop would be the most likely place to blow a fuse or transistor.
When batteries are full regen doesn't work as there is no place to put the power.
Please think about this before you proceed down this path.
Bob

Here is the front brakes on front of a tesla model S
34270

[Gary Livingston]

Hi Bob,

Yes I get your point . . . and ,of course they would be functional. I was just trying to get my point across to help people understand what I was searching for. Also, it will have AWD and all wheel regen braking, tune-able for front rear distribution of course.

Of course the Tesla modelS is only rear wheel drive, so. . . very significant point to have front wheel brakes since they tend to do most of the braking.

[Turboguy]

Gary, perhaps you would benefit from going back and re-reading Bob's post again. I am left with the impression that you did not get his point.

[Gary Livingston]

It wouldn't be the first time Turbo. . . lol OK so I read it again. I think I got it all the first time. The problem is I think with my original description. It doesn't paint a very accurate picture of what I want. In fact it is rather misleading. It sounds as though I want no brakes at all. I should have started by saying that I would have 4 wheel regen that would have helped Bob and others realize I wasn't trying to stop this thing with rear wheel regen only. Let me try again.
Most brakes on performance cars are over sized to deal with the heat build up that occurs from multiple high energy events. This is what this thread is really focused on. My set up, under normal driving (and racing) won't have this issue as the brake pads will seldom, if ever be engaged. That said, they still need to be capable of stopping the car, especially as Bob points out, in some kind of failure mode. But this ability does not need to be engineered to accommodate the additional heat build up of non-regenerative applications. So, most of the high end performance brake components focus on reduced weight and increased friction capability as well as heat dissipation. My focus is on reducing the unsprung weight primarily while still maintaining the capability to stop the car if needed. There are likely few if any components designed with this in mind. So, questions like, will "rear brakes fit on the front" and such become potentially viable options. The Tesla example is a bit off because it deals with a very heavy rear wheel drive only vehicle. We all know that front brakes tend to 70% of the stopping. . or at least some number above 50%.

Regarding safety, most cars have three separate systems. The master cylinders are made with dual pistons and separate hydraulic systems to separate the front from the rear and reduce the failure mode impact. The third is the ebrake. Mine will have 5 systems. The three described plus the front and rear electric drive systems which are completely separate systems.

Bob is 100% correct though, I do agree with him in the context is was written. Plus he has a lot more experience than I do in this field.

regards,
Gary

[Gary Livingston]

A question for Subaru gurus. . . is there not some alternative to the drum ebrake system? In my mind, this is terrible. I want to loose this weight. An ebrake can be incorporated into the caliper. I just did the brakes on my daughters VW beetle a few weeks ago. It has a lever which mechanically rotates and forces the caliper piston forward. Weight would be fractional. Complication is a 1 compared to a 9. What are the options? Do we have to fit VW brakes?

[Bob_n_Cincy]

Hi Gary
The Tesla model S is a very low center of gravity car. So brake shifting to the front wheels is not as pronounces as most cars.
The 818 is similar in the respect.

This is a picture of the Tesla rear brakes. It is a 4 pot caliper. It also has a separate small caliper for the e-brake. it is an electrically activated parking brake, which engages automatically when you put the car in park
34300
bob

[Gary Livingston]

Hey Bob. Thanks! I'm a bit perplexed by the "Emergency" vs "parking" brake thing. The emergency brake may serve also as a parking brake, but not vice versa as I understand it. I once tried to apply my "parking" brake on the volt when I was going down a slippery, snow covered hill in the winter. The front wheels started to skid (due to regen, I might add. . . which I have an issue with and need to try and convince GM to change their algorithm for regen on slippery roads)f Anyways, using the ebrake is something I have done many times in this situation. Putting the transmission in neutral also make a big difference and can stop this situation often as most who drive in winter conditions would likely know. Anyways, I hit the going down this hill to engage the rear brakes more and nothing happens. They seem to work only as a parking brake! Not impressed.!

[Turboguy]

Gary- I still think you're missing some of the message here. Actually the majority of it --well-- actually ALL of it.

Your original post left no confusion either, so let's not back-pedal here: in a nutshell, you are looking for the absolute minimum installation that will 'look like' a real brake system, so you can slide through a safety inspection and get your car licensed for road use. The brake system that you describe would not be capable of stopping the car in a reasonably safe distance, let alone in a repeated stop situation. Most motorcycles are equipped with beefier braking systems than you propose for your 818.

In short, regenerative brakes are a great 'environmental' feature but they are woefully inadequate on their own for street use.........and would be absolutely laughable at the track (which you imply you will be going to by mentioning 'racing'). They are an assistive technology, not a replacement for a traditional brake system. It doesn't matter whether they are engaged on 2 wheels or all 4. The fact of the matter is that traditional brakes can apply 4 to 6 times the torque to a wheel than a regenerative system can. Unless your 818 is riding on bicycle tires, a modern mechanical brake system will generate far, far better stopping performance. Regenerative brakes also have failure modes which could very well cost you, your passenger -or another motorist- their life.


I believe Bob's responses, in part, are to demonstrate that even the most current state-of-the-art electric vehicle includes a high performance mechanical braking system at the same level as those found on very high performance cars. A braking system that would be completely capable of stopping the car in short order all on it's own.


Bob has been very diplomatic in his replies. As a fellow motorist sharing the roads in Ontario with you, I am not.

[Scargo]

From article about Porsche race cars using regenerative braking (http://www.popularmechanics.com/cars/alternative-fuel/hybrids/porsche-911-gt3r-hybrid-flywheel):
"In motorsports, drivers accelerate and brake a lot harder and a lot more frequently than the average commuter. The rate at which a chemical battery can absorb and release this energy is limited, and rapid charging/discharging causes it to overheat and form cracks in its electrodes. That's why hybrid vehicles are typically limited to about 0.3 g's of deceleration from regen braking. Race cars like the 911 Hybrid racer typically decelerate at over 1 g."

Most passenger cars can only realistically achieve .7 g's. This came from an internet article.
Thus, I would think .3 g's would be decent braking. I doubt it would throw anyone through a windshield, but it might give them a headache if they were unrestrained during a sudden application of the brakes. Around one G of acceleration keeps people pinned in their seat.

[Jaime]

You don't have to store the braking power. If you just put a big motor on all four wheel and connect the two wires of each motor together, you'll lock up all four wheels. That's exactly how the electric brake on a cordless tool works.

[Goldwing]

Yep, R/C cars have been doing that for a few decades now as well.

We might need to have our first beer summit. One of the best parts of this forum is the lack of arguments and trolling. Quite the opposite of many forums (NASIOC included), even repeat questions aren't barked at and usually linked to a helpful post or the advice is simply administered. I love that about this place. We just help each other out. Please understand the initial posts left a few with genuine concern. Things snowballed from there. Reading the above, there was enough room to lead to confusion. So, let's try a reset, a mulligan, whatever. Maybe it's the new dad in me, but I hesitate to lighten the capability of the brakes, even if the plan is to rarely use their capability. Perhaps you could compare the weights of various years of WRX's and swap to a lighter year? You'll likely find someone willing to trade with you if you have the 4 pot/ 2 pot setup on your donor. I might suggest, looking to lighter wheels, lighter suspension pieces, and maybe a lighter weight rotor first.

If you're skilled at fabricating, I had zero problems with my turbo beetle that had brakes you described above, and it's a similar weight car to a wrx. Remember that we are foregoing brake boost, so you would want to compare brake system pressures to be sure. It seems a lot of trouble for a few pounds, that while nicely integrated, does lose a little bit of redundancy. I like the separate brake pad setup of our ebrake. The caliper can fall off the car, and the ebrake will still work. Remember though, I'm a new dad, and paranoid and stuff.

Insert favorite beer here and enjoy.

[Sgt.Gator]

A question for Subaru gurus. . . is there not some alternative to the drum ebrake system? In my mind, this is terrible. I want to loose this weight. An ebrake can be incorporated into the caliper. I just did the brakes on my daughters VW beetle a few weeks ago. It has a lever which mechanically rotates and forces the caliper piston forward. Weight would be fractional. Complication is a 1 compared to a 9. What are the options? Do we have to fit VW brakes?

Check this out: http://store.revolutionbrake.com/mrparepabrso.html

[David Hodgkins]

Sorry guys, I had to remove 4 posts. Let's keep it civil please.

:)

[xxguitarist]

In case this is still about moderate upgrades for the stock braking system ;-)

We will be putting good brake fluid in from the beginning (whatever the yellow colored equivalent of the superblue is), and checking out the pads that came with the car- Lots of material left, but I suspect a bit weak.
If we replace, it'll be with EBC yellowstuff most likely. Good pad for auto-x weekends, while still street-able. A roadcourse would be asking a little too much of them.

[flynntuna]

Thought this thread should be bumped with all the brake discussion lately .

Found this on nasioc...


http://forums.nasioc.com/forums/showthread.php?t=1265631

[Innkeepr]

Looking at upgrading our donor while the boy is still driving it (04 RS sedan)
Has anyone had experience with the "power stop" brand calipers ? I found these at autoparts warehouse. They say direct replacement, and they are powder-coated red (bonus).
front and rear can be had for about $350. Adding the Centric rotors & pads adds another 275.
If this a good option for the 818C ? or am I wasting time because there is something better/cheaper ( don't belong in the same sentence..right)

Thanks for the input.
"E"

[Scargo]

From what I've read (at Summit's site) is that they are rebuilt calipers and many have various minor issues. Some, not that minor...
Given that they may not be perfect or you may have to return one or more of them to get a good, full set, then they may be a bargain.

[redfogo]

I have never had an issue with remanufactured calipers any any car. But I can't really say I have ever ordered that specific set.

[Bob_n_Cincy]

Looking at upgrading our donor while the boy is still driving it (04 RS sedan)
Has anyone had experience with the "power stop" brand calipers ? I found these at autoparts warehouse. They say direct replacement, and they are powder-coated red (bonus).
front and rear can be had for about $350. Adding the Centric rotors & pads adds another 275.
If this a good option for the 818C ? or am I wasting time because there is something better/cheaper ( don't belong in the same sentence..right)

Thanks for the input.
"E"

I would stick with the OEM brakes until you get the 818 running and then evaluate what you need.
Some are happy with OEM.
Some went with high performance pads.
Some went to expensive ap racing, brembo or wilwood brakes.
I went with larger OEM calipers in the rear and street/autocross/trackday pads all around. I am happy.
Bob

[Rasmus]

Just found another one for this thread.

Cadillac ATS-V (Brembo) calipers and 2004 STi Brake Rotors (the 5x100 ones) installed on a 5x100 Subaru (WRX).

it's about $650-$690 if you get all new parts but you get:
http://i.imgur.com/NGRe0CL.jpg

Head to this website: www.ctsvbrakeswap.com/

[Scargo]

That's a great idea for getting to STi level braking for cheap. Also opens the door for better and lighter rotors. Which, if I digress, makes me think about 5X114 wheels... (were I to have 5X100s)
After looking at the CTSV brake swap site (http://www.ctsvbrakeswap.com/) I went to their Facebook page (https://www.facebook.com/ctsvbrakeswap/), where there are lots of pictures and more info. Looking at what's involved I wonder what stops people from welding on a new boss and bypassing the adapter kit? I guess I've been fabbing and welding so long that it seems like a no-brainer.

[Samiam1017]

i don't believe they have a rear break upgrade, I don't have my car far enough along but I believe the car needs tons more rear brake before a front upgrade is in order?

[Wayne Presley]

i don't believe they have a rear break upgrade, I don't have my car far enough along but I believe the car needs tons more rear brake before a front upgrade is in order?

We have a winner

[Bob_n_Cincy]

i don't believe they have a rear break upgrade, I don't have my car far enough along but I believe the car needs tons more rear brake before a front upgrade is in order?


We have a winner

We ran 96 laps this past weekend at NCM 3.15 mile Grand Course.
Running front 04 FXT calipers on all 4 corners. PV on rears turned down 4 revolutions.
After 10 hot laps and a cool down lap, the back side of the pads were 220f front and 300f rear.

52672

The rear rotor I am running is designed to put sti brakes on a 5x100 wrx with 170mm ebrake.

I totally agree with Wayne and Samiam about the rear is where upgrades are warranted.
Bob

[Rasmus]

Clearly I've been out of the loop for a while. I'll have keep in mind that those that have actually been to the track with this car are heating up the rear brakes more than the fronts. Thanks fellas.

[MiniVanMan]

Looks like the ATS-V uses a 6 piston on the front and a 4 on the back. The conversion kit is for using the 4 piston on the front of the 818. So, that begs the question, who wants to model up a bracket/adapter for the rears to use the same 4 piston?

4 piston calipers all around, then adjust bias as necessary, which sounds like you shouldn't need to do much.

Sexy looking brakes with more than enough braking power, and with the additional braking power in the rear that is evidently needed. All for around $1300.00 with rotors and pads.

Plus, digging around, the parts are easy to source new.

Calipers are only $135.00 at Summit. They're Brembos supplied by AC Delco, AND they're aluminum. Somebody please do this. If you need to be spotted a caliper to do this, I'll be happy to oblige. Or somebody tell me I'm way off track.

http://www.summitracing.com/oh/parts/ado-172-2587/overview/year/2015/make/cadillac/model/ats

[Rasmus]

Looking at what's involved I wonder what stops people from welding on a new boss and bypassing the adapter kit? I guess I've been fabbing and welding so long that it seems like a no-brainer.

Glyn you must have some serious welding skills. I've taken a welding class at the local community college so I know if I tried to weld new bosses onto a cast iron knuckle I'd be without brakes soon. I just don't have the skills to trust that those welds would hold without cracking. If the knuckle was steel I might give it a go. Cast iron's a big nope.

[Mitch Wright]

Here is the rear adapter mount we made for the AP calipers I am using. the Black anidized adaptor is a bolt-on adaptor for the front from a BRZ brake kit which works on the WRX upright.
http://thefactoryfiveforum.com/showt...-arrived/page2

[DodgyTim]

I put a second set of the 2006 4 pots fronts on the rear, with larger diameter (316 mm) 5x100 rotors, to give better rear brakes and a slight rear bias.
It was cheap to do but took some time to modify the standard backing plates and machine the calliper mounts a little
http://thefactoryfiveforum.com/showthread.php?18211-Subaru-4-pot-front-callipers-on-the-front-and-the-rear
I still haven't really tested them in anger

[Scargo]

...If the knuckle was steel I might give it a go. Cast iron's a big nope.
I understand your concerns and they are warranted. There is filler rod specifically for cast iron and cast iron to steel. I had a Chevy where the owner and builder was an aeronautical engineer. He welded material to the spindles to convert it to disc brakes. He did have welds magnafluxed and he shot-peened everything. I am not sure if he did any annealing. I know picking the right filler is critical.
When I welded the up-pipes out of 321 SS I back-purged my welds with Argon to prevent oxidation of the back side of the welds, which is a known issue and causes serious weakening. I talked to a guy who does pretty exhaust work and no back-purging, so that ended our conversation. Full Race back-purges all their 316 welds.

[flynntuna]

Bumping this thread, I'm going to do the H6 rear upgrade that's been discussed here and on the Subaru forum. The caliper brackets I'm looking at on Rockauto are like $20 and rotors I'm considering are $59. Are these the right brackets?

https://www.rockauto.com/en/catalog/subaru,2004,outback,3.0l+h6,1426867,brake+&+wheel+hub,rotor,1896

https://www.rockauto.com/en/catalog/subaru,2004,outback,3.0l+h6,1426867,brake+&+wheel+hub,caliper+bracket,1714

[Bob_n_Cincy]

Bumping this thread, I'm going to do the H6 rear upgrade that's been discussed here and on the Subaru forum. The caliper brackets I'm looking at on Rockauto are like $20 and rotors I'm considering are $59. Are these the right brackets?

https://www.rockauto.com/en/catalog/subaru,2004,outback,3.0l+h6,1426867,brake+&+wheel+hub,rotor,1896

https://www.rockauto.com/en/catalog/subaru,2004,outback,3.0l+h6,1426867,brake+&+wheel+hub,caliper+bracket,1714

This rear brake upgrade will give you better rear rotors cooling. The H6 rotors are bigger, so some increase in performance. What you really need is more braking force from the rear wheels.

I don't know if your parts are correct.
Bob

[flynntuna]

This rear brake upgrade will give you better rear rotors cooling. The H6 rotors are bigger, so some increase in performance. What you really need is more braking force from the rear wheels.

I don't know if your parts are correct.
Bob

True, but I have the Wilwood pedal box and planning on using the EBC yellow stuff pads. Hopefully it will be enough for a starting point. If not the I can upgrade from there.

[bow2091]

If you have not bought anything yet this Ebay # 292159266302 may be a option they also carry just calipers and brackets Ebay # 391850470943

[flynntuna]

Thanks for the links, but, this mod only replaces the capilper bracket to accomadate the larger rotor of the H6 outback. It keeps the stock caliper. While this mod by itself doesn't improve performance by much, it does improve cooling like Bob said in an earlier post and looks better in the wheel. :cool:
I'm hoping the the ability of the balance bar on the Wilwood pedal box and the yellow stuff pads as I said in my previous post will be enough for my needs.

https://forums.nasioc.com/forums/showthread.php?t=522006
http://www.scoobymods.com/showthread.php/usdm-2000-legacy-rear-disc-814.html?s=&threadid=814

[Bob_n_Cincy]

I'm hoping the the ability of the balance bar on the Wilwood pedal box and the yellow stuff pads as I said in my previous post will be enough for my needs.


You will be good to go fast with those 2 changes.
Bob

[tmoretta]

Is the H6 upgrade still considered an effective way to get more rear braking effort? My 818S has '02 WRX brakes (2 pot, 1 pot) and even with my bias valves limiting pressure to the front brakes, the rear brakes never lock. Any advantage to changing to 2 pot rear calipers?

[DanielsDM]

Any advantage to changing to 2 pot rear calipers?
Yes! Check out Frankc5r's thread on brake calculations.
The rear has more weight than the front and with the low COG there is less rear to front weight transfer under braking. The pressure limiting bias valve on the front is not a very good solution.

[phil1734]

The 2-pot calipers Frank suggests are wilwoods and have twice the piston area.

The Subaru 2-pot rears still have the same piston area as the single pots, so the only improvement comes from a marginally larger brake reaction moment since the calipers are mounted further out. I'm not sure what the piston area of the H6 calipers are, but I believe it's a similar situation.

For the cost involved and what is at stake, use Frank's wilwoods or adapt a set of front calipers.

[frankc5r]

The Wilwoods are very nice but do cost more than
adapting the stock fronts to rear like Bob
and Cincy.

[flynntuna]

I think I remember :confused: somewhere reading here on the forum of putting for street applications of standard brake pads in the front and yellow stuff in the rear. Does anyone else remember this, or am I imagining this?

[tmoretta]

I am currently running HP + pads in front, yellows in rear. Not a satisfactory solution.

[frankc5r]

I think I remember :confused: somewhere reading here on the forum of putting for street applications of standard brake pads in the front and yellow stuff in the rear. Does anyone else remember this, or am I imagining this?

My brake calc program showed a minor improvement with higher mu pads.

[tmoretta]

Is my '02 WRX rear caliper the same as the H6 rear caliper? So I only would then need to source the H6 brackets and larger diameter rotors?

[frankc5r]

Is my '02 WRX rear caliper the same as the H6 rear caliper? So I only would then need to source the H6 brackets and larger diameter rotors?

Not sure about that but the WRX rear caliper has small piston and is not the best to use.

[flynntuna]

Here's a link for interchangeable brakes

http://www.rs25.com/forums/f9/t221786-brake-interchangeability-faq.html

[EODTech87]

The caliper is the same. I originally purchased everything for the H6 rear conversion but decided I'm going Wilwood rears now.

[tmoretta]

Do you have those H6 parts to sell? PM me if so.

[flynntuna]

Grassroots motorsports magazine has a good article to add to the discussion....http://grassrootsmotorsports.com/articles/grm-vault-grassroots-guide-braking-systems/

[Scargo]

Grassroots motorsports magazine has a good article to add to the discussion....http://grassrootsmotorsports.com/articles/grm-vault-grassroots-guide-braking-systems/
Though dated, it is pretty good for those starting out or with little experience with brakes and racing. Written by "Staff Writer", I was a bit amused by how they started the Brake Pad section, where they contradict themselves about friction and then say the pads push against the rotors when it is the caliper's pistons that do the pushing. But that's minor and just hit me as odd in an overall good article.
I've known that pads not up to racing environs can literally crumble and fall apart from excessive heat but I thought of fade as a fluid only issue. Sorta like, the pads work or they don't work, given how much heat they are exposed to, not that they can go from good friction to lousy friction and work with varying degrees of efficiency based on heat and actually get to the "fade stage" quickly.
OTOH, now that I think about it, I have had a rare instance where Hawk DTC 70's got to where I ran out of brake and pushing harder on the pedal did not help and did not cause the ABS to engage.

[lsfourwheeler]

Grassroots motorsports magazine has a good article to add to the discussion....http://grassrootsmotorsports.com/articles/grm-vault-grassroots-guide-braking-systems/

If I'm honest, I think that article is quite misleading when it comes to their brake pad explanation. The pads 100% are responsible for the stopping and especially under high-temp conditions such as the track. That said, and perhaps what they were trying to get at, is for street usage a more aggressive pad will not reduce stopping distances. This is true as even the worst brakes on a new car today have the capability of locking up the tires and/or engaging ABS thus the real determining factor in street stopping distance is tire grip. But on track, a high temp pad is very important just as high temp fluid is. Both items contribute to the sensation of brake fade when they reach temperatures beyond their ideal operating range and both will degrade braking performance in those situations. When fluid boils, you have to push the pedal further for a desired braking force. When a pad overheats, you have to press the pedal harder for a desired braking force. Both can be unnerving to experience on track.

[flynntuna]

I have a newbie question. Do all non STI brake calipers have the same thread size and pitch for the hose connections? Can WRX brake lines be used on forester calipers?
I found out that WRX uses m10x1.00 on the banjo bolts from the Cobb website , wondering though if stainless steel brake lines are interchangeable ?

https://cobbtuning.zendesk.com/hc/en-us/articles/200025184-Subaru-Thread-Pitch-and-Hardware-Information

Thanks in advance

[Bob_n_Cincy]

I have a newbie question. Do all non STI brake calipers have the same thread size and pitch for the hose connections? Can WRX brake lines be used on forester calipers?
I found out that WRX uses m10x1.00 on the banjo bolts from the Cobb website , wondering though if stainless steel brake lines are interchangeable ?

https://cobbtuning.zendesk.com/hc/en-us/articles/200025184-Subaru-Thread-Pitch-and-Hardware-Information

Thanks in advance

My 07 & 06 NA impreza were M10x1.0
Also 'My 04 &05 Forester XT were M10 x 1.0
All cast iron calipers.
Bob

[Scargo]

I think Bob's correct and I can add that my '07 & '08 STi are the same and I think '05-'06 are too. Otherwise, differences in hoses are subtle.

[Mitch Wright]

I have AP calipers rotors on my R https://www.essexparts.com/essex-designed-ap-racing-competition-brake-kit-front-cp8350299brzfrsgt86 front and rear with DS2500 pads https://www.essexparts.com/ferodo-ds2500-brake-pads655 The brakes are awesome. The front is a bolt on to a WRX upright. I had a make and adaptor for the rear.