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Got my wheel/tire setup installed, and the results are...puzzling

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Alright guys, after multiple threads asking advice on wheel and tire setups, I finally bought everything and had it installed. Unfortunately, it didn't turn out quite like I expected. So here's the setup:
Forgestar F14's
Front: 19x10 +41 285/35/19 MPSS
Rear: 19x11 +53 305/35/19 MPSS

I had this setup designed by a popular vendor, so I was really hopeful that it would work well. The fronts ended up rubbing the inner wheel well liner just a little bit at full lock, which was solved with a small amount of trimming. The rears, however, are rubbing substantially on the inner wheel well liner. I know the MPSS run super wide, and the rim protector on them is definitely part of the problem, but there are multiple places in which the tire is rubbing alot, as well as a place where the wheel itself is in contact with the liner. I've seen other people using these offsets, so what is the deal with mine? Is it because I'm lowered on T Springs? I am also using an adjustable panhard rod (that is centered).

In addition, it looks to me like the fronts stick out of the fenders, while the rears are recessed in the fenders. It could be because of the way the tires fit (the fronts are a little bulgy and the rears arent), its hard to tell. But I don't know how im going to solve my rubbing problem, I do not want to cut out half the inner wheel liners. Especially when I was assured this setup would work well. Anyway, here are pics:

13043776_10208824275861614_4401130703961814886_n.jpg


13055440_10208824276141621_3379641224460390295_n.jpg


13061941_10208824276501630_8049991730298142537_n.jpg


13076547_10208824277221648_2318652911913222248_n.jpg


13062315_10208824277381652_6368447921781344464_n.jpg


What do you guys think of the fitment? Does it look normal?

And has anyone else had problems with a 19x11 +53 rubbing on the inner wheel well liner?
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
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arabbit said:
So here's the setup:
Forgestar F14's
Front: 19x10 +41 285/35/19 MPSS
Rear: 19x11 +53 305/35/19 MPSS

I had this setup designed by a popular vendor, so I was really hopeful that it would work well.

Especially when I was assured this setup would work well.

Arabbit:

Sorry to learn about the fitment issues.

However in view of your above statements, you have to go right back to the vendor for answers and the fix.

Did you check the actual offset of the wheels, (it's cast on the inner side of the wheel spokes)? Maybe they are different from your invoice? Good luck and let us know how you make out.

302 Hi Pro
 
The rear wheels look like they are too far in. The tire should almost be rubbing the inside of the outer wheel well opening. Looks like there is a lot of room there. Front looks good for not having a lot of camber.
 
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I've had a very similar issue with forgestar and MPSS. My guess is the same person speced them out. Only answer I've gotten is its the MPSS and need to go smaller.77ccb80442b2efa50c0e14bb81ff0834.jpgf1be829b56d3360c003230f36a4d7341.jpg


Sent from my iPhone using Tapatalk
 
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Ahh another person bitten by the oversized MPSS curse. Sorry you have joined our club!

Front: 19x10 ET41 is what I ran on my CF5s at all 4 corners and never had any rubbing with 285/35/19 Bridgestone RE-11s, but the MPSS is a wider tire in the same size. I am wondering how much camber you have because I was at 1.7 degrees on P springs first then lowered even more on KW coilovers (and a little more camber) and never got any rub, even during aggressive driving over bumps. The extra width of the Michelins is probably the root cause.

Rear: 19x11 ET53 is a size I have heard of but am unfamiliar with personally. If you look at one of the big Mustang Forgestar vendors (American Muscle), they spec out their CF5 and F14 19x11s at 56mm, which means the rear tires sits a little further inboard than yours do. So I am really surprised that your wheel (the actual wheel, not the tire) is rubbing on the liner.

The 305/35/19 PSS is actually a narrow tire for it's width (10.7" treadwidth vs 11.8" treadwidth for the 305/30/20 PSS, although both are listed at 12.3" section width), but it is a littler taller than OE. I know you said that you have adjusted your PHB to center the body over the axle, but you might want to double check via plumb bob just to make sure because even 1/4" can make a huge difference with rubbing (my 295/30/20 PSS rubbed on one side even though I was positive that the axle was centered - a double-check revealed I was off by about 1/8" and fixing that made the difference).

Anyway, I can completely understand your frustration because you just spent a lot of $$$ and it isn't working right. Hopefully your vendor can help out. Good luck!

John
 
Yeah I don't understand how it's rubbing either. I'm going to take it back to the tire shop this week and have them measure the offset to make sure it is indeed correct. Like you guys, I have been told that the MPSS are to blame. However, when the tire techs looked at it, they told me that no matter the tire, it would rub due to the construction of the wheel. And after looking at it closer myself, it looks like that is true, because it isn't only the tire that's rubbing, the wheel itself is touching the liner too. If it was stock height, it probably would've worked but being lowered, it's rubbing like crazy. Which is frustrating, because I informed the vendor of my mods before everything was built.
 
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You should have about 8-3/32" of backspace with a +53 offset. That puts the rim about flush with the outside fender. I have a 305/30/19 MPSS tire and don't rub but I have a Watts link which might help. Do both tires rub or just one? If just one than it could be an adjustment issue or the panhard bar arc is enough to cause a rub. I thought The T springs are pretty soft so with the extra grip with the wider rubber you might have more body roll. My track set-up uses a +55 18" CF5 with the 305 35 18 nittos and that doesn't rub either.
 
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What frustrates me here is that Michelin can just make tires that are too big for the size. How is this cool? I can't even figure out if I go from my 285/35/20 to 275/35/20 if it will work.

It's driving me nuts


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They rub on both sides the same way, it doesn't appear to be an alignment issue. And yes, it frustrates me too, I don't know how these tires stay in production with sizing like this.
 
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Tire size depends on the manufacturer, at best a specific size is "close" but I've seen a lot of difference between manufacturers, the simple way out is a set of quality spacers, Eibach makes some decent ones that I've autocrossed on before. Just make sure the studs penetrate enough to be secure.
 

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