Feedback on 235/40 18 on the front
 

Please provide your feedback on the use of 235/40 18 on the front axle and 295/30 18 on the rear. I want to fit a set of PS2's and from the reseach I've done its still within the 4% tolerance given by Porsche for 4WD...

Has anyone had PSM or Diff problems? How does the car handle?

Curious to know as well.

I have the PS2s with 235/40/18 in front and 295/30/18 in back. No PSM or Diff problems so far. I haven't taken it on the track yet, but turn in does feel better. I don't think the front tire diameter is different enough to trigger the PSM.

I did some research and this is what I found but still need to hear your opinions, this diameter issue shouldn't be an issue since the 235/40 is (when both new) 1,7% bigger than the 295's.

New 225/ new 295 = 0.5%
new 225/worn 295 = 1,8%
new 235/ new 295 = 1,7%
New 235/worn 295 = 2,6%

Which is the same as 225 new/295 worn combination and EVEN on the new235/worn 295 combination is still within the 4% tolerance given by Porsche as PCNA tecnical advisers answered here on a similar question.

http://www.pca.org/tech/tech_qa_question.asp?id={66185E6B-B499-4E70-8A9B-D7E57E43B5DA}

No one has anything to add?

I am running 235 front and 315 rear with no problems. I think the diameter of these tires is virtually identical. I doubt 235 fr and 295 rear would trigger any problems.

I would go for it. the extra grip in front will come in handy.

I'm running 245/40/18 front and 335/30/18 rear (9" wide front and 11.5" rears). TOYO RA1's.

Spidey, do the 335's rub?

No they dont, even with PSS9's and "almost" Gt2 ride height.

Pic attached. I'll measure clearance tomorrow.

i'm thinking about getting the toyo's for track use on stock rims. will i have any rubing problems. i have the stock sus but plan on installing jiz in future. how do like the ra1s? 245f and 335r??

I run Mich Pilot Sport Cups 235/40 and 315/30 on stock rims with H&R coil overs. I do have rubbing in the rear on the inside back. They had to pull back with zip ties so the tires would not rub...FYI.

As well, my HRE rims for the street rubbed too.

bumping this one, curious if there are any new thoughts on this...

I replied in detail on the Rennlist thread, but in short love my 235/40 & 295/30/18 Advan AD08Rs....