Rear Wilwood Brake Alignment

[metros]

I have the front wilwood kit adjusted and installed perfectly. With the front caliper mount you're able to use provided shims to get the caliper and brake pads adjusted to the edge of the rotor perfectly. That way you don't have the brake pads overhanging the edge of the rotor.

However, with the rear kit you're limited to the mounting holes on the hub, which obviously aren't adjustable. Both sides have the brake pads hanging outside the rotor by 1/8". The performance won't be noticeably impacted, but leaving the brake pads with a high spot like that will end up crumbling the pads on the outside edge. The only way I can think to get the pads to sit closer to the center is to hog the mounting holes out, which would potentially allow the calipers to move. Not something I'd like to compromise.

http://i100.photobucket.com/albums/m35/mxmetros6/818%20Build%20Album/20140703_214625_zpsydkdqrs3.jpg

Ideas?

[Boog]

I can only assume that there is enough additional space (distance for increased rotor diameter) to cause there to not be an overhang when mounted on whatever car these were originally designed for.

Worst case scenario we need to find a new rotor with the same bolt pattern, hub diameter, shoe diameter and width, and disk offset and approx thickness but is 15mm larger in diameter?

[C.Plavan]

This may sound crazy, but did you happen to mix up the front and rear rotors? The rears are actually a tad bigger in diameter than the fronts. I thought that was weird.

[metros]

Doesn't sound crazy at all. When assembling I only worked on one end at a time because of that. Sizes have been confirmed as correct. Front are 12" and rears are a touch over 12".

[Frank818]

12.19" rear, yes.
The Wilwood manual doesn't say anything for the rear adjustment? They just assume it fits perfect?
I will get the parts out of the box tomorrow, so I have not checked yet.

[Slatt]

Or maybe Wilwood sent the brackets for the other kit, the 12.88"?

[Frank818]

Metros, I thought I'd install my rear ones yesterday, but I broke off a hat bolt and after 2h I couldn't succeed to drill through it, so that ate up most of my time yesterday. Then the removing of the heat shield, then the grinding and cutting of the 2 ears on the back plate of each side (4), I was about to fit one caliper but the lower ear was not cut enough and then I was out of time. :( Next Saturday I will know if I have the same prob as you with the pads.

[Jaime]

Mine overhang too.

http://i871.photobucket.com/albums/ab273/jaime398/818%20Build/20140706_112652_zpswy7ukdsh.jpg

There's plenty of room to move in.

http://i871.photobucket.com/albums/ab273/jaime398/818%20Build/20140706_112756_zpszylapi5h.jpg

[metros]

Mine has plenty of room to move in as well. But the only way I see to do that is hog the mounting holes out, which worries me about strength of the final set up. The mounting bracket could be part of the problem. I'll be contacting Wilwood about this once I get a chance.

[Frank818]

I was about to contact them (next w-e) if I get that prob too. I guess if we are 2 to contact them for the same kit, same car (WRX), they might light up some bulbs in their brains.

[C.Plavan]

I popped off my rear wheel- Mine are the same. Not too worried about it.

http://i.imgur.com/JKRYB8Ol.jpg

[Frank818]

Why are you not too worried, Chad?

[C.Plavan]

Why are you not too worried, Chad?

Just because they are the rear brakes. If it were the front, I would be pissed. I think you guys are right though. I think their measurements for the adapter are off. Maybe they don't know.

[longislandwrx]

what's the thermal expansion of a 12.19" steel rotor?

I thought a rule of thumb was .001 per inch per 100 degrees Fahrenheit so get those things to 600 degrees and you'll expand .030 that will get you closer to the pads edge.

[Frank818]

Same problem here as well.

312413124231243

[Frank818]

@metros
@Jaime

Remind me your Wilwood part # for the rear kit?
140-7006 1999-2004 Impreza WRX?

[metros]

I have the same overall part number for the rear kit 140-7006. The caliper mount bracket part number in question is 250-6982. That's the actual part that would provide different placement of the caliper.

[Frank818]

Same caliper bracket part number, man.

I mailed Wilwood on Sat night, no answer yet, but hey it's Sunday, I'll give them a chance. :)

[metros]

IIRC they're only open M-F, which would explain the lack of response. I'm also going to try emailing and including a picture. Hopefully tomorrow while I'm on work time.

[Frank818]

Big places are often closed on w-es and I was joking about the lack of response cuz I knew they weren't open. :)
Big places also sometimes tend to not listen to little situations like this one. So we'll see... I guess if we are 2-3 to send them the same issue they might do something.

[metros]

Just emailed, included that I'll be reporting back here with the response.

[Frank818]

I was expecting that:


Thank you for your inquiry with Wilwood Disc Brakes. We have sold quite a number of these kits, none of which that have had any issues. For any type of warranty claim please give us a call at 805-388-1188.

Not sure yet what I'll do. It's not a warranty claim I need, it's a bracket fix.

[metros]

I haven't gotten any email back. Give them a call then.

[Frank818]

Well according to the new FFR R build thread, there is a Wilwood guy participating to the build. I think that guy could help us, he works for Wilwood so he certainly could sneak in the info to someone. I'll ask the thread.

[metros]

They asked me for pictures today. Just sent them many pictures of the whole rear assembly. Looking forward to any input they can provide.

[D Clary]

I think the problem could be where they glued the pad material to the backing plate. with passenger car replacement pads there is a great variation of material size and position. If wilwood has no great fix, I am with Chad it is no big deal. I would just bevel the top of the pads to so they will not lip over as they wear. Even if they do lip over it will only cause noise it will not alter their effectiveness.

[Frank818]

Even if they do lip over it will only cause noise

Which is really annoying on a street car. :(

[metros]

Wilwood has replied back asking for my contact information. They've been researching the issue and are looking into the chance for a manufacturing defect.

So far they're at least trying to verify where the problem is. Can't complain about that.

[Frank818]

I envy you! Let's see what they come up with and if they send you a new bracket, I will mail them back asking for one.

I knew it's always better when we are more than 1 to send the same question/situation/issue. :)

I just feel sad that Wilwood is totally inconsistent in their replies. :(

[C.Plavan]

Any update? I wonder if I order pads from a different manufacturer (Race Pads) if they will be off- (If brake pads were glued wrong)- otherwise the bracket is off.

[metros]

If this many of us are having the same problem I believe it's the bracket. Something along the way was tweaked or adjusted from the original. Or I'm hoping they didn't see the pad overhang and say close enough.

Haven't heard from them again since last week.

[Frank818]

Any update? I wonder if I order pads from a different manufacturer (Race Pads) if they will be off- (If brake pads were glued wrong)- otherwise the bracket is off.

Are you the 3rd one who sent them an email about that lately?

[bossman43]

If this many of us are having the same problem I believe it's the bracket. Something along the way was tweaked or adjusted from the original. Or I'm hoping they didn't see the pad overhang and say close enough.

Haven't heard from them again since last week.

metros, please keep us updated. I have the same issue...

31906

[Frank818]

Yup, exactly the same thing! If you have some time, it'd be appreciated if you could advise them as well, like I said, the more we are to send them an email about this issue, the better. :)

[C.Plavan]

On the phone now with them.... they are confused because they dont offer a rear kit for the 818........ I explained its a Wrx rear from a 02- 05.

I sent them this link also. Please reply with your donor year for clarity.

Email: pictures and MY to rbennett@wilwood.com Thats who I talked with. We need this fixed.

[metros]

My donor is also a 2002 subaru wrx.

Tell him to speak to some of his colleagues as they have told me they're doing some research into the issue as well. Although they never gave me a name via e-mail.

[C.Plavan]

My donor is also a 2002 subaru wrx.

Tell him to speak to some of his colleagues as they have told me they're doing some research into the issue as well. Although they never gave me a name via e-mail.

He was aware. I just don't understand what is taking so long. It's not like it is an isolated event. Everyone here is having the same issue.

[Frank818]

On the phone now with them.... they are confused because they dont offer a rear kit for the 818........ I explained its a Wrx rear from a 02- 05.

I sent them this link also. Please reply with your donor year for clarity.

Email: pictures and MY to rbennett@wilwood.com Thats who I talked with. We need this fixed.

Chad, you want us to send an email with the details to R. Bennett? You damn bet I will if that's what you were saying.

Of course there is no 818 kit loll, I even specified the part #, in my case, when I mailed them a few weeks ago. And I never mentioned 818, to make sure no confusion.

[C.Plavan]

Official Response....... Basically, thanks for pointing it out- We designed it that way (but we did not know).

This is unacceptable for a $1000+ kit. If I would of known, I would of not bought it. Should be pretty noisy for you street guys. What do you guys think?

"Greetings Chad,

This is the official response that I have received and been requested to send to our customers with the 140-7006-R kit.

Wilwood brake kit 140-7006 does indeed have a pad overhang. The top of the pad sits about .125” above the top of the rotor. This is an unfortunate interaction between all of the design elements those of us in the aftermarket performance parts business are confronted with on a daily basis. The factory upright uses an internal drum parking brake with a backing plate that doubles as the caliper mount. In an effort to keep cost down and make installation easy, the backing plate and internal drum brake are retained. We then attempt to use as many off the shelf Wilwood components as possible to complete the kit.

In this case, the factory caliper mounts extend pretty far from the center of the axle. They’re nearly the same center to center distance as our caliper mounts. This means that the Wilwood caliper mount ears would interfere with the Subaru caliper mounts if we tried to push the caliper any lower. We could create a new billet caliper with narrow mounts and a lower mounting height. This would switch the kit from using a high volume caliper to using an application specific, low volume caliper. The costs for an application specific, low volume caliper is about double the cost of current caliper. That would likely add $200 or more to the price of the brake kit.

The next option would be to use a larger diameter rotor. The rotor required would need to be 12.45” in diameter to match up with the top of the pad. While this would solve the problem, it’s also expensive. We would need to have a new casting made which incurs tooling costs and a minimum order of 1,000 pieces. That’s roughly a 10 year supply of an application specific part at current sales levels. A new rotor would likely raise the brake kit price more than a new caliper.

We prioritize keeping the cost of our products within reach of our consumers, so the decision was made to let the pad overhang the rotor a little rather than drive up costs. The overhang may make a mathematical reduction in brake torque versus a pad that is flush with the top of the rotor; however, the real world difference would be nearly impossible to detect. The friction material overhanging the rotor will break off easily (if not on its own) and won’t cause any problems. All in all, it comes down to a cost/benefit analysis; and in this case the benefit of keeping the brake kit affordable was chosen as the overhang problem seems minimal and fixing it would be expensive.

All that being said, we are looking into options for correcting the pad overhang, and we’d like our customers weigh in on the issue. As a customer would you be willing to pay an extra couple hundred dollars for a kit without the pad overhang? Would you be interested in retrofitting the kit you already purchased if it cost a couple hundred dollars? Considering the extra costs, would you make the same choice we did and live with the overhang? Email us at customerreply@wilwood.com and let us know what you think.

Ryan"

[D Clary]

This is pretty much what I would expect from the aftermarket aims at tuner guys who wouldn't even notice the overhang or care about the noise,( and there will be noise.) I think the simplest solution for them is to redesign the pad so it doesn't overhang but they probably wont. You may look at other pad manufacturers to see if their pads fit differently. I have not installed my rear brakes yet so I will cross this bridge soon. If the overhang is only 1/8 I will probably bevel the pads and run it.

[Frank818]

What I think, Chad? Couple of things.

First, we now know they sell 100 per year of these kits. loll

Second, I totally understand their decision and it makes sense, sometimes in R&D you hit a wall for which AT THAT TIME no solution is a winner and compromises arise. Add 2 points to Wilwood.
That being said, they SHOULD have at least written that info on their installation sheets. To at least advise the buyers of that problem and why. Even better, to advise before buying, saying the kit is not a perfect fit and blahblahblah. Deduct 10 points to Wilwood.

Third, yes I'd pay an extra $200 to get an application specific caliper, IF I cannot easily remove the pad material myself to prevent any noise. I do not want noise anymore on my brakes of any of my cars, sick of that.

I will mail them about my choice.

[metros]

Wow, that's incredibly disappointing. I don't understand why they couldn't use the same caliper mount with different bolt position for the caliper mount side. We're already grinding the ears off the tabs to fit the caliper as is. A little more would make a big difference as 1/8" that I'm getting is too much.

I too would have purchased another kit had I known. Sure it would cost a little more but I'm a perfectionist. I installed/removed the fronts probably 5x to get the perfect fit with the shims.

I will also be emailing.

[C.Plavan]

After one track day you can see the grooves from Wilwoods bad math..... (stock pads suck- I went with a racing compound now)
http://i.imgur.com/JNsfbHAl.jpg

[Hobby Racer]

Chad - what compound pads are you running now?

[C.Plavan]

Chad - what compound pads are you running now?

Raybestos racing compound ST45

[Hobby Racer]

Raybestos racing compound ST45

Have you ever tried Essex RC6 sintered pads? I run them on my Lotus Elise and love them!

[DMC7492]

Here's what belt sander massaging produces. Just like the rest of the project, custom engineering to "my liking"
50457

[RetroRacing]

We made custom mounting brackets to get the pads in the right place.

[Frank818]

I wonder if a bench grinder with a 60 or 90-grit wheel would do it too?

Pretty nice what you did!

[metros]

We made custom mounting brackets to get the pads in the right place.

Pics? Maybe you could sell the design to wilwood and spend some time educating them.

[DSR-3]

Are you willing to share drawings, dimensions, ? I would rather make my own too, but I don't have any of the rear brake .parts to measure, etc.

We made custom mounting brackets to get the pads in the right place.

[metros]

Craig should create a bracket on wilwoods behalf. Clearly their team can't hack it.

[RetroRacing]

I will take some pics and measurements when I get back from Palm Springs in a week. It was not to tough to do, but does require welding.