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Discussion Starter #1
Thinking about running a square setup to dial out a bit more understeer and allow me to rotate the tires. Running Dinan springs and sways on stock shocks right now.
Plus, a second set of wheels means a set for summer and a set for winter/all-season. This car is my daily.

Searching around this forum, I found the following threads:
I know owners have good luck with the 19x9.5 stock wheels with 20mm spacers up front. Then maybe a 10 or 12.5 out back to even up the stance.

No good pictures in those threads, though!

Anyone running anything like this and got pictures or experience with it? Rubbing issues?

I want aggressive, but not crazy, and I absolutely do not want to have to pull/roll the fenders.

So my hope, order a set of Forgestar F14 in 19x9.5 ET18. That way I run a 10mm spacer up front, none out back.
 

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There is a guy who ran 265/35 on all four. I just put my fronts 255/40, on the back with 15mm spacers and my backs 285/35, on the front with 8mm spacers. Everything fits but I haven't had a chance to drive it yet. I may drive it and get some pics tomorrow.
 

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Not sure why you care about understeer for a daily driver but... I ran 275/35/18s BFG R1s and needed 15mm spacers on the front. 12mm was not enough. They barely cleared the fenders using stock front geometry. You could add some camber to help if you have issues. Apex Arc-8 18x9.5, offset 22.

Most R tires are notoriously wider than street ones. There's no way a 285 R-spec would fit as Alan just tried with street rubber I assume.
 

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Here it is, 255/40-19, 8.5 wheel on the rear with 15mm spacers. 285/35-19, 9.5 wheel on the front with 8mm spacers. I think 275/35 would be just right.
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Just did a full day at the Ridge Motorsports track. A bunch of us were giving guest rides to celebrate the opening of the new clubhouse. We did four ninety minute sessions swapping passengers every 10-15min. I went through four tanks of fuel. It was pouring down rain most of the time!

Anyway the set up worked fine. Dropping down the hill from the carousel I would here a little rub. I inspected the tires and wheel wells and did not see any evidence of rubbing. There was one small spot on the inside of the fender that was bent but again I didn't see and evidence of rubbing. I guess you could get away with 285/ 35 up front if you really wanted to push it.
 

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Wait, wouldn't you have the opposite problem with 255s in the rear? Especially in the wet...

One thing that's a cheap/easy fix is to use the M6 sway bar in the rear, it's 2mm thicker IIRC.
 

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If you are talking about oversteer? I just was out with the Porsche club at a CCC. I volunteered so after the CCC was over the volunteers got to run on the autocross and a modified figure eight. I was really pushing the car to oversteer. Of course I was not ripping the throttle, in fact it was only set at 400hp. It was totally controllable, I could oversteer through a gate or around a pointer into a salom. If I had 285's on the rear it would have been even better/faster.

Getting as much rubber as you can on the track holding the weight is one goal. Being able to rotate the tires and get maximum life out of the tire is another goal. To that end the organizer of the last event that has several race cars also flips his tires. You flip the tire on the wheel and then mount the wheel on the opposite side of the car. Now the outside edge is the inside and you can finish wearing the tire. All of the groves cut into a tire are to allow water to be pushed out from under the tire. If you are on a track you really don't care about that, wear it down to the chords. When you spending $350-500 per tire and getting a few thousand miles you want to make them last. Just like the brakes, $500-800 a set for a few thousand miles. The rotors stay on until the are toast.
 

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As to your comment about sway bars. I'm not sure when you are pushing hard it really makes much difference? It would force the opposite wheel down in a corner to maintain contact. Adding a few mm may not be worth the effort. It really takes coilovers too get the adjustment and stability for a real improvement in traction at the limit.
 

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Discussion Starter #10
I actually ended up deciding not to go for wheels. Car has almost 100,000 on it. I can't make it make sense to spend much on wheels when the car is probably worth $15k.

Thanks for the input, all!
 

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I did a 10" square setup on mine for around a year
Hey Dan, which 2Forge Wheels are you running? What offset & tire sizes?
 
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