W i d e Body

[Vman7]

Thought I would just throw this out there. Has anybody thought about a wide body version based on the current 818 design?

David

[Rasmus]

Do it.
http://i539.photobucket.com/albums/ff355/Brittani-94/DSCN0874-1.jpg
Only way to fit 335/35R17 Kumho Ecsta XS tires under there.

[RM1SepEx]

that's a big beastly tire!

[D2W]

Thought I would just throw this out there. Has anybody thought about a wide body version based on the current 818 design?

David

^I know a guy who has the talent to photoshop it^

[Vman7]

^I know a guy who has the talent to photoshop it^

lol........

[bbjones121]

Vman7 you back in action?

[Vman7]

Vman7 you back in action?

Not yet, at least on the 818. Still waiting to get some things confirmed and get some more detailed pictures to work with. Mostly working on GTM stuff right now. I might play around with a front/side shot of the 818 for a wide body. I am debating about posting some mock-up front view ideas I did sometime back.

David

[jimgood]

There's a threshold in tire width at which point you will not be able to get enough heat into the tires to make them stick. I have no idea what is that threshold, but I wouldn't jones for wider tires until FFR has a chance to find the optimal width. And they will.

[bromikl]

There's a threshold in tire width at which point you will not be able to get enough heat into the tires to make them stick.

Right on. Wide tires may look cool, but sometimes narrow tires perform better - especially in rain or snow.

[metalmaker12]

To run more than a 255-275 at most you will have to change the lower rear control arm set up drastically, which I already knew but I asked this question to Jim anyway. He confirmed. Plus the 818 is already rather wide, the way its designed. You want the car to grip, but you also want it to slide when you want.

[Vman7]

Yeah that is the big ?, is just how wide can we go before it gets to the point where there is no benefit.

I was thinking no more then 1"-1.5" per/side up front, and no more then 1.5"-2" per/side in the rear. The more I look at the 818 there are a few ways to give it a wider look without really going to wide, mostly by getting rid the the fender lips and bringing the rest of the fender out to where the lip used to be.

Tire sizes I had in mind are the same ones I based my Vantage on.

These are the tires on the Vantage that I ended up with:
Track: Front- 58.5" / Rear- 58.3"

Tires: Front 225/40-18 / Rear 255/35-18

Tires Opt. Front 235/40-18 / Rear 265/35-18, 275/35-18

Here are the tires sizes I used when deciding on which ones to go with:

------------Tire Size / SW/ DIA
Front/Rear 225/45-17 / 8.9" / 25"
opt. Rear 255/40-17 / 10" / 25"

opt. Front 225/40-18 / 8.9"/ 25.1"
opt. Rear 255/35-18 / 10" /25"

opt. Front 235/40-18 / 9.3" /25.4"
opt. Rear 265/35-18 / 10.4" / 25.3"
opt. Rear 275/35-18 / 10.8" / 25.6"

[Vman7]

Vman7 you back in action?

I put up some front mock-ups. They are ok, but not what I really have in mind. Just a few ideas I sometime back.
http://thefactoryfiveforum.com/showthread.php?8906-Vman-s-818-Design-Mod-s

I started working on some others the last day or so, just need a better picture. The one I used is ok, view is right on, just not a real good picture.

[metalmaker12]

I like this front design, it is cool and makes it look meaner, I need to get a design program, I got some good ideas to put down.

[Vman7]

I like this front design, it is cool and makes it look meaner, I need to get a design program, I got some good ideas to put down.

Which front design are you talking about?
I just use photoshop for right now. If you can somewhat layout your idea, so I (someone) can get an idea of your ideas, I or someone can draw them up.

[FFR-ADV]

I need to get a design program, I got some good ideas to put down.

Hi metalmaker12,

No question Photoshop is top of the line. If you want to try something low cost (FREE) you might want to try GIMP. There are many Youtube videos of how to use the program to edit cars, just search for: Gimp cars. I look forward to seeing you get your ideas onto the screen.

Vman7,

I really like what you are doing with the 818. The front almost has fangs ;) and the back end mod screams "Super Car"

Cheers!

[bnr32jason]

I think the widebody issue could easily be solved with simple fender flares or perhaps some riveted on blister fenders. If they are designed correctly they shouldn't look tacky at all. We can very likely squeeze a 235 in the front without much issue with stock width, not sure if there is need for more front tire on such a light car. But it seems from the look of the photos we've seen from the track testing day, 255's in the rear are already pushing it. So put on some widen it by about 30-40 mm's on each side and we should be able to throw 285's or maybe even some 305 R-compounds on it.

[0100]

235/40-18 and 265/35-18 street tires should fit no problem on the stock 818 body with the proper wheel width and offset.

[Red Tag]

I was already planning on a wide body, or more likely fender flares (I like fender flares). The main issue is tire selections. As Jimgood pointed out, one of the keys is to get heat into the tires, especially for track use. This is more of a tire compound issue than size. From my point of view the best tire size / selection out there are the Hoosier A6/R6 range. They heat up quickly and provide tremendous grip. The BFG R1 are very good and wear like iron, but may have an issue getting heat into them.

I am planning on using 265/35R18 fronts and 285/30R18 Michelin Pilot Sport Cups (already have a set) for the street and A6/R6 for the track.

VMAN, are you using ALIAS for your surfacing? I plan to and use the wireframes to create the molds. I need to recreate the front suspension on Inventor and finalize the wheel offsets, make adapters, and order wheels/tires. I really wish we had data from the actual cars so I can start cutting steel and get out of this planning mode.

[Vman7]

VMAN, are you using ALIAS for your surfacing? I plan to and use the wireframes to create the molds. I need to recreate the front suspension on Inventor and finalize the wheel offsets, make adapters, and order wheels/tires. I really wish we had data from the actual cars so I can start cutting steel and get out of this planning mode.

No, right now I do everything in Photoshop.

[Samiam1017]

I've seen tire sizes for the two cars listed but what are the wheels sizes and offsets? Are they out there somewere?

[Red Tag]

I'm not 100% sure, but I think the tires/wheels on the SEMA 818S were:
Front: 225/40R17, 17"X8", offset = 35mm
Rear: 255/35R18, 18"X9", offset = 35mm

(Stock WRX wheels/tires are P205/55R16 on 16"X6.5", offset = 53mm)

[Red Tag]

1565715658

I took pictures of the front and rear suspension, and I do not know if you can tell from the pictures, but both the front and rear are constrained inward by the suspension links. The only way bigger than the wheels and tires shown at SEMA / Moochfest is to go outward, resulting in fender flairs or a widebody.

[Mechie3]

I(Stock WRX wheels/tires are P205/55R16 on 16"X6.5", offset = 53mm)

06 WRX has stock wheels with these parameters:
Stock wheel dimensions: 17 x 7.0"
Stock wheel offset: 53mm
Stock tire: 205/50R17

[0100]

The front has like 3 inches of space before you even have to think about fender flairs.

15681

[Matty_STi]

265 fronts 285 rears would be perfect. beyond that you will have to rely on down force, HP and heavy braking to build enough heat.. Tire width thresholds only come into play when you can't build enough heat in the tread to make them sticky bigger issue on R-compound and slicks than with smaller tread block high performance tires. Course you can go so wide and heavy that the engine just bogs down but i would think if you need to run 275+tread you've the power already to use that grip.

275 also would be a good.

I wouldn't run any less than 255's on my build, but then again I am going to be putting upwards of 700whp to the pavement and making sure to eek out all the downforce and aero goodness that I can. maaayyybe 295 read and 275 fronts if they fit thought goofing the suspension all up. Though that can always be fixed with some re-engineering.

Also subscribed to thread.

-Matt

[bnr32jason]

700whp?! May I ask why so much power? That is approaching F1 levels of power to weight ratio.

[longislandwrx]

I wouldn't run any less than 255's on my build, but then again I am going to be putting upwards of 700whp

-Matt
WOAH.

I don't think you could pull this off reliably for under $50k and probably alot more... but I would love to read a new thread about your build.
There also the question of whether the chassis is designed to withstand anywhere near that much power without overstressing it.

[Martin]

I don't think anyone has ever managed to break an FFR chassis because of too much power.

The chassis is one of the main reasons a lot of people go for an FFR. Apart from being a piece of art work to look at, they are designed for racing and extreme use.

I'm not saying you couldn't break it, but there is an FFR GTM with 1200hp in it, they were breaking the wheels loose before the chassis had any problems. With the roadster, there are cars out there with upwards of 800hp, and they are struggling with traction and gear boxes *LONG* before the chassis gives up any surprises.

Martin



WOAH.

I don't think you could pull this off reliably for under $50k and probably alot more... but I would love to read a new thread about your build.
There also the question of whether the chassis is designed to withstand anywhere near that much power without overstressing it.

[carbon fiber]

700 hp!? good luck keeping it on the road. this car is rwd only and LIGHT. at that level, traction control would be an absolute must. i'm putting around 500-550 in my gtm and that's pushing traction. once you go so high with hp, it's only good in a straight line. attempting to put power down coming out of a turn would be hairy at best.

[Erik W. Treves]

Yeah.. 700 RWHP... really?? I think you reach the point/risk of just throwing money at something just to say you have a number. My Roadster at 2550 lbs has more HP and TQ than most and after actually driving it around for 3+ years....I can tell you that I would probably never build one like that again...probably....It's neat to roast the tires at 100...but you have to be ON all the time in a car like that and it is metally exhausting...if I am at all tired or not feeling 100% I don't even attempt to get behind the wheel of that car...Not to get this off topic..though.. so I will stop right there.

[Nuul]

Yeah.. 700 RWHP... really?? I think you reach the point/risk of just throwing money at something just to say you have a number. My Roadster at 2550 lbs has more HP and TQ than most and after actually driving it around for 3+ years....I can tell you that I would probably never build one like that again...probably....It's neat to roast the tires at 100...but you have to be ON all the time in a car like that and it is metally exhausting...if I am at all tired or not feeling 100% I don't even attempt to get behind the wheel of that car...Not to get this off topic..though.. so I will stop right there.

I know what you mean. I decided I wanted "only" 300HP for the reasons you listed. Especially since we're not going to have traction control or any of the modern go fast helpers that you'd get with a BMW/Porsche/etc. 700HP is just asking to end up on the news. I see we're getting very derailed so I'll shut up now.

[carbon fiber]

that mentally exhausting part is spot on, you're NEVER relaxed while driving it. i've got a '91 mustang notch with 600hp @ 2900 lbs. and it's a handful. forget driving it in the rain, ever. fun to roast 'em at 100mph plus with a roll on, but not fun trying to turn and accelerate. aftermarket traction control is available and would help, but it's still going to be a handful.

[Xusia]

Yeah.. 700 RWHP... really?? I think you reach the point/risk of just throwing money at something just to say you have a number. My Roadster at 2550 lbs has more HP and TQ than most and after actually driving it around for 3+ years....I can tell you that I would probably never build one like that again...probably....It's neat to roast the tires at 100...but you have to be ON all the time in a car like that and it is metally exhausting...if I am at all tired or not feeling 100% I don't even attempt to get behind the wheel of that car...Not to get this off topic..though.. so I will stop right there.

Eric is spot on. My sportbike has a power-to-weight ratio of 3.65 pounds (my weight included) per HP, and it's a handful to ride. I honestly have more fun riding my buddy's 600 with only 5.6 pounds per HP - and it's because I don't have to spend the mental energy to be the traction control. I can give it a handful of throttle coming off a corner and not worry near as much because I don't have to be as precise. Sure, I'd get more acceleration on my bike, but for me it's about fun, not lap times or other numbers. Because of this, I'm planning on ~250 RWHP for my 818. It will still faster than most cars, but a lot easier to drive. :)

[carbon fiber]

i know what you mean. i've got a 2007 cbr1000rr with some mods and it's addictive as far as the speed in a straight line. but on twisty roads i still miss my 600. lots more corner speed. i used to wear out the tires from corner speed, now they wear out from the extra weight. i can't win!

[Mechie3]

He won't have problems driving a 700whp car for a few reasons.

1: 700whp is 823 bhp. I remember back in 2007 (?) the first privatetly owned STI broke 800hp. All the other (by all, I mean the very few) that also did that were all shop owned cars who spent way too much money and time doing this.

2: 700whp will break the 5 speed. It will break all 5 speed gears available. It will even break the stock 6 speed. He won't go very far.

3: If he's sticking with a 2.5motor, his turbo won't spool until really late. This guy only makes 400hp peak, but at 4500rpms he's still only making 200hp. There's a local guy with an STI that makes up to 500 some hp (he has different maps). He puts it on the low map because it's undriveable with AWD at anything higher that his low hp map.

http://www.ionperformance.com/dyno/050403dyno2.jpg

I find it hard to take him seriously, at all.

[longislandwrx]

He has a pretty serious build planned.

http://forums.nasioc.com/forums/showthread.php?t=2442916

talking about a $5000 ECU here so who knows, maybe his pockets are a big as his goals. Calling him on it now seems premature.

[carbon fiber]

auto x with 650-700hp? more like doughnut competitions.

[Mechie3]

I'm not saying he couldnt' do it with enough money, just that I find it hard to take someone who thinks an 818 needs or will do well with 700whp seriously. ;) His thread does say 600whp too, which is more easily obtained than 700whp. That old 80/20 rule.

Also, I've seen too many people come and go with the "I'm going to build X00 hp" and nothing happens. I didn't know he had that other thread, so I'll at least take his build seriously, but not that in an 818.

It'd sure be interesting to see, but in the end, it's like the old Supra joke. What's the difference between a 1000hp and a 500hp supra? They both run 11's. In an AWD Subaru, sure, in an 818? Don't think it'll be worth it.

[Erik W. Treves]

He has a pretty serious build planned.

http://forums.nasioc.com/forums/showthread.php?t=2442916

talking about a $5000 ECU here so who knows, maybe his pockets are a big as his goals. Calling him on it now seems premature.

nobody was saying you couldn't do it...but from the perspective and experience of off the chart HP to Weight building, the point being, that for real life enjoyment of actually being able to drive the car every day..not really reasonable...doing 700HP in a WRX is nothing and really do mean NOTHING...did I say that strongly enough...NOTHING like doing it in a 2500# Cobra let alone 1800# 818...but to each his own...game , set, match.....how about that wide body thread....

[timmy318]

Dang...... 700 HP??????

[longislandwrx]

doing 700HP in a WRX is nothing and really do mean NOTHING...did I say that strongly enough...NOTHING like doing it in a 2500# Cobra let alone 1800# 818...but to each his own.

I'm right there with you. preaching to the choir...

I was referring to Mechie saying hard to take him seriously... even though I have to agree somewhat, just giving him the chance.


I remember reading along time ago, back when Steve Millen was at the top of the Nissan game. His team at Stillen had built an insane 300zx with the biggest turbos available at the time and every other mod under the sun. It made a ridiculous amount of power. They gave the car to Steve who took it out for a spin. He returned a while later, handed back the keys and uttered one word. "Undrivable" End of project.

Insane projects do do one thing, they set the bar.

[metalmaker12]

Silly if you ask me, 700whp in an sti is crazy enough. You might get power to weight kinda close to an f1, but you will never get close to that overall performance in any 818, never going to happen. Even if I was loaded and could do it, I wouldn't. I think 400-500 whp is asking for it, but hell to each there own build

[Mechie3]

I'd rather see him build a 400hp motor and spend the rest of his money doing more development on the 818 (suspension, body work, aero, etc). That would be more fun to see.

I will gladly eat my words humbly if he actually does build a 700hp 818.

[metalmaker12]

+1 mechie, but if he does, it will be undrivable

[Oppenheimer]

Crazy dollar builds with crazy power, that is what the GTM is for (among other things). Silly to do that in the 818. But its his $.

[Matty_STi]

I'm not saying he couldnt' do it with enough money, just that I find it hard to take someone who thinks an 818 needs or will do well with 700whp seriously. ;) His thread does say 600whp too, which is more easily obtained than 700whp. That old 80/20 rule.

Also, I've seen too many people come and go with the "I'm going to build X00 hp" and nothing happens. I didn't know he had that other thread, so I'll at least take his build seriously, but not that in an 818.

It'd sure be interesting to see, but in the end, it's like the old Supra joke. What's the difference between a 1000hp and a 500hp supra? They both run 11's. In an AWD Subaru, sure, in an 818? Don't think it'll be worth it.

okay everybody sloooooooooow doooooown

My motor build for my STi is in capable hands but until that finishes my STi build is at a stand still. 818 will be somewhat similar

I changed my goals for my 818 and haven't updated to reflect that. My 818 won't be used for anything other than track days and as a way to play around with some crazy ideas I have. 700whp is absolute max. And also i'll be using a syvecs as well. The nice thing about the syvecs is I can dial in a tonne of different maps and flip them on the fly, also per gear boost settings, built in TCS and lots of other goodies. 700whp will be for mile events and straight line stuff. More likely to be around 500-550 for track days.

If anyone thinks that I would try to get 700whp to hook up in 1st or 2nd or even 3rd gear is out of their minds. I will be running nice sticky r-comp rubber but that can only do so much. Aero and ECU control be my aces for this.

Aero is a big focus on this build and I have lots of cool tricks up my sleeve for that. As for lag, well I am going to try my hand at getting a holset variable turbo to play around with, there are other options available too. The weakness of the 5 speed isn't a big deal for me, there are lots of options out there that are superior i've got a few discussions going on with a couple different vendors.

This isn't a quest for mine bigger than yours or to impress anyone if I wanted to do that I sure as hell wouldn't be using an EJ series as the base and i wouldn't stop at 700.. The 818 is a great platform for me to play around with, that's it. I would use an elise or an exige but I wouldn't want to butcher either as I love lotus's.

There is more thought going into this build than most and over engineering is the name of the game. This also isn't my first high hp crazy build, but I don't want this to be like other stupid high hp builds so I am going to be doing things differently..

Also I am a young un-married (though not single) fairly well off guy. I don't plan on having kids nor does my gf for quite a long time.

Either way, I expect there to be lots of flack for a build like this. I also know it will be very expensive, and I also know it will take a lot of time and be a giant headache.. I'll live with it.. Oh and if I can't get things to work properly don't think I won't be the first to admit I f'd up.

Anyways my goal wasn't to hijack this thread... so If people want to discuss the merits of my build PM (good/bad/whatever). I haven't started the build yet so no point in a build thread it will just turn into a pile of crap before things actually get done. No need to get your feathers ruffled yet, too soon for that. :)

okay, back to the thread. (seriously guys don't clutter this thread, PM me or start a different thread, I will start a build thread when I am ready to start building).

Matt

**EDIT**

I should add I like doing off the wall projects, big ideas change things. That's why I have the money to do crazy projects because in my line of work big ideas go places - it's why my friends/peers, all of whom are well educated and in great jobs, make a fraction of what I do.

I could build a 400hp 818, but there will be lots of those.. I don't want to build just a 700whp freak machine that tries to kill me (aka frank profera's insane lotus), I want to build one that can be driven, and driven fast. Sure I want to scare my pants off sometimes but I still want something drivable. I think that can be done. The goal is 700whp, that goal could change depending on testing. And sure there are the insane GTM builds, I don't want to build a GTM, at least not yet. I believe I could do something crazy with this project that won't be replicatible. Why do what everyone else has done? That's formulaic and boring. If it was easy I wouldn't want to do it. These are kit cars for projects - this is my project - the 818 has no set goal other than a small lightweight kit based on wrx running gear. You all may not want to build a 700whp car or think it can't be done or think it will be a disaster piece, doesn't mean I don't think it can be done. Just because you wouldn't or couldn't doesn't mean others can't and won't - and do a kick *** job of it.. The spirit of my build is to try stuff, see what happens and push the limits, it can be done and done in a smart way.

*EDIT 2*

It's really weird and kinda freaky when people talk about you/refer to you in the third person... lol

[bbjones121]

So anyways, how about that wide body? Love the new work on the front Vman.

[Vman7]

Well that was interesting.......lol Actually I enjoyed reading a lot of this stuff, got some education from a lot of it.

[Movieman]

Just a thought: I never rain on anyones parade..700HP,7000HP, I just wish them luck.
Like an old story I heard years ago about this guy who was going to put a Alison P51 engine in a 64 Chev malibu..I chuckled and said Yea, sure and then he did it..
You build your dream Sir and the best of luck to you!

[philly15]

holset FTW! thats my input lol im gonna be looking into some borg warner stuff for future build plans.....

[bnr32jason]

Well, 700whp and widebody are things that actually should be discussed together. Because I'm pretty sure even R-compounds aren't going to stick unless you've got 300mm+ tire on the back.

[Mechie3]

Lots of words!!

I'll admit an apology is due on my part. I jumped the gun a little. I'm a moderator on 2 Subaru forums and the number of people that come in and talk big and gather a huge fan club that says "OMG you're so awesome!" and then disappear without ever accomplishing anything is astounding. You had all the marks of one of those people: big goals (bigger than anything else), and a low post count.

I would like to see you start a build thread. Whether it works or not, it'll be fun to see it come together and perhaps spread ideas around as well.

[longislandwrx]

Back to the thread.. just looking at all the pictures posted it seems like 255's in the front would not be an issue, seems like plenty of room to the knuckles and to the fenders to get another 30mm.

hey if I can run a 255/35R18 all around that just means I can rotate my tires. 295 Hoosiers all around with some flairs would be crazy for track days. I don't know if my kidneys are up for the challenge though.

[metalmaker12]

Good luck Matty, get a build tread going, your still nuts lol:D

[THE ITALIAN]

I'm with Eric on the HP issue. My Roadster is mild compared to most although when I bring up this subject on the old forum, I get blasted.
I like to run straight when I take off without very much spin & when I shift the car goes forward, not sideways.
I've even been accused of not being able to spend the dollars on an insane motor.
Horse power is nothing if you can't turn a corner without having fun. I would rather babysit my skill, rather than babysit control.
As far as a wide body, Jeniffer Lopez's butt is too big for me, not for some.(dam that thing is big) A good flare in the back of the 818 would be nice IF it could actually work toward an advantage, and not something that breaks - that Turbo Porsche look has always been my fav- I would leave the front alone and maybe drop it to push weight toward the front more

By the way; they don't often show J lows butt on those magazine covers now do they? the page is only 8.5 inches wide

[flynntuna]

Lol

[Vman7]

I thought I would bring this subject up again, since right now I am somewhat working on the 818 2.0 and 818 GT versions.

The 818 GT version would be the one either with/without a wider body. If not wider, it would have the look of being wider, mostly in the rear.

My question is what wider tires for best performance would be within reason without going crazy, so I determine how much wider to go on the body design.

David

Post #11 (http://thefactoryfiveforum.com/showthread.php?9222-W-i-d-e-Body&p=90694&viewfull=1#post90694)

[Plebeian]

I think Sponaugle is using 275's on his build.

[ehansen007]

Yeah.. 700 RWHP... really?? I think you reach the point/risk of just throwing money at something just to say you have a number. My Roadster at 2550 lbs has more HP and TQ than most and after actually driving it around for 3+ years....I can tell you that I would probably never build one like that again...probably....It's neat to roast the tires at 100...but you have to be ON all the time in a car like that and it is metally exhausting...if I am at all tired or not feeling 100% I don't even attempt to get behind the wheel of that car...Not to get this off topic..though.. so I will stop right there.

Hey! What do you know about pal?????!!!!! Oh wait.....sorry...

e :)

[carbon fiber]

Maybe we can ask Matty_STi... oh, nevermind.:p Seriously, 275 rear, 245 front? That's seems pretty reasonable. Anything past that and you'd probably come up against the geometry/getting heat in the tires issues. Also, just more rotating mass. David, what about the idea of the widebody being part of the 4.0 vantage design? I like what Hennessy did with the Lotus Elise:3776537764

[Vman7]

Maybe we can ask Matty_STi... oh, nevermind.:p Seriously, 275 rear, 245 front? That's seems pretty reasonable. Anything past that and you'd probably come up against the geometry/getting heat in the tires issues. Also, just more rotating mass. David, what about the idea of the widebody being part of the 4.0 vantage design? I like what Hennessy did with the Lotus Elise:3776537764

That's what I was thinking when I designed the Vantage. Tires I posted in Post #1, max being 235 front/275 rear.

The Vantage 4.0 was going to be a combo of the current 818 body/vantage 3.0, but when I tired doing some of work, it doesn't look possible with doing real major body changes. So I figured the Vantage 4.0 should just be an alt body on it's own.

Lotus Elise/Exige is I like a lot. The Hennessy Venom, from my understanding was based on the Exige. The Elise and Exige are pretty close, unless you know what to look for, most ppl would know the difference.

Anyhoot, back to the widebody. I started working on the 818 2.0, then once that is done, I'll start working on the 818 GT, which will either have the look of a widebody or will be wider. I just have to find out what is the max tire width for the 818 right now to determine how much wider to go with the widebody and just how wide of tires.

David

[Vman7]

Yeah that is the big ?, is just how wide can we go before it gets to the point where there is no benefit.

I was thinking no more then 1"-1.5" per/side up front, and no more then 1.5"-2" per/side in the rear. The more I look at the 818 there are a few ways to give it a wider look without really going to wide, mostly by getting rid the the fender lips and bringing the rest of the fender out to where the lip used to be.

Tire sizes I had in mind are the same ones I based my Vantage on.

These are the tires on the Vantage that I ended up with:
Track: Front- 58.5" / Rear- 58.3"

Tires: Front 225/40-18 / Rear 255/35-18

Tires Opt. Front 235/40-18 / Rear 265/35-18, 275/35-18

Here are the tires sizes I used when deciding on which ones to go with:

------------Tire Size / SW/ DIA
Front/Rear 225/45-17 / 8.9" / 25"
opt. Rear 255/40-17 / 10" / 25"

opt. Front 225/40-18 / 8.9"/ 25.1"
opt. Rear 255/35-18 / 10" /25"

opt. Front 235/40-18 / 9.3" /25.4"
opt. Rear 265/35-18 / 10.4" / 25.3"
opt. Rear 275/35-18 / 10.8" / 25.6"


Here is what I need answers to:

1. What is the max tire width & height the 818 can handle right now?

2. What is the max tire width & height without compormising performance?

By knowing the answer to the above two questions, I can determine how much wider to design the widebody.

thanks :)
David

[ph1tnessjunk1e]

To run more than a 255-275 at most you will have to change the lower rear control arm set up drastically, which I already knew but I asked this question to Jim anyway. He confirmed. Plus the 818 is already rather wide, the way its designed. You want the car to grip, but you also want it to slide when you want.

Couldn't you buy wheels with negative offset to keep from making major control arm changes?




Here is what I need answers to:

1. What is the max tire width & height the 818 can handle right now?

2. What is the max tire width & height without compormising performance?

By knowing the answer to the above two questions, I can determine how much wider to design the widebody.

thanks :)
David

How do you go about determining the answers to the above questions?

[Scargo]

You have forgotten the power factor for the "not compromising performance" question #2. Unless that's known then it can't be seriously answered.

To #1, I only know that you can get a 275x40x18 under the rear on a 32ET rim. I have 9.5" wide 17's with 32 ET on the rear and they work fine on my STi upright. I'm putting 245X40 Conti's on them today and I foresee no issues at all. The front on mine is not Subaru so I don't know if anything I do there will be valid for your research.
I don't see why you can't start with a known entity, like what some here have done successfully and work from there. Using a rim with relatively high ET, you can use washers or big nuts behind the wheel to vary and reduce the offset. Make tire profile silhouettes and tack the profile in with hot-melt, tape, etc. Rotate them around while in bump and full lock. Once you have removed the shock it should be a simple matter to move it around and evaluate the fit of the combo.

[Vman7]

Couldn't you buy wheels with negative offset to keep from making major control arm changes?





How do you go about determining the answers to the above questions?


You have forgotten the power factor for the "not compromising performance" question #2. Unless that's known then it can't be seriously answered.

To #1, I only know that you can get a 275x40x18 under the rear on a 32ET rim. I have 9.5" wide 17's with 32 ET on the rear and they work fine on my STi upright. I'm putting 245X40 Conti's on them today and I foresee no issues at all. The front on mine is not Subaru so I don't know if anything I do there will be valid for your research.
I don't see why you can't start with a known entity, like what some here have done successfully and work from there. Using a rim with relatively high ET, you can use washers or big nuts behind the wheel to vary and reduce the offset. Make tire profile silhouettes and tack the profile in with hot-melt, tape, etc. Rotate them around while in bump and full lock. Once you have removed the shock it should be a simple matter to move it around and evaluate the fit of the combo.

Basicly I would need the answers in post #62, which would come mostly from ppl who have worked on the 818 and have pretty much for the most part have figured out the max tire sizes etc.

Unfortunately at this point it really doesn't matter, since I am not working on 818 stuff anymore, as I posted in my Vman's 818 Design Ideas thread post #95 (http://thefactoryfiveforum.com/showthread.php?16689-Vman-s-818-Design-Ideas&p=185764&viewfull=1#post185764)

David