Feedback on 235/40 18 on the front
#1
02-11-2006, 04:16 PM
Join Date: Jul 2005
Location: Porto/Portugal
Age: 46
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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?
Has anyone had PSM or Diff problems? How does the car handle?
#3
02-11-2006, 08:01 PM
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.
#4
02-11-2006, 08:17 PM
Join Date: Jul 2005
Location: Porto/Portugal
Age: 46
Posts: 429
Rep Power: 36
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}
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}
#7
02-12-2006, 10:14 PM
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#10
02-14-2006, 12:35 AM
Originally Posted by ebaker
Spidey, do the 335's rub?
Pic attached. I'll measure clearance tomorrow.
Last edited by spidey; 09-23-2006 at 10:30 AM.
#11
02-14-2006, 11:49 AM
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??
#12
02-14-2006, 07:46 PM
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Join Date: Oct 2005
Location: Alpharetta, GA
Age: 58
Posts: 152
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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.
As well, my HRE rims for the street rubbed too.
#15
09-22-2018, 01:17 PM
For street driving maybe the combo 235/40 + 295/30 might work but on the track, i am pretty sure the psm and abs go crazy,
And I wouldnt believe any given tire diameter on the web. Ask the tire company directly.
You will be surprised sometimes.
simply use 255/35
And I wouldnt believe any given tire diameter on the web. Ask the tire company directly.
You will be surprised sometimes.
simply use 255/35
Last edited by ghostofpain; 09-22-2018 at 01:20 PM.