Tire size question - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Allen K. Littlefield · 06-30-2009, 06:36 PM

My '02 2.7 Tip has 7x17 front and 8.5x17 rear wheels. The current tire # is 205.50zr for front and 225.40zr for rear. Over the past months I have not seen the 225.40zr advertised for the rear but rather 225.45zr. Would this tire size be problematic to replace the .40zrs? Just want to make sure so any help appreciated and thanks in advance.

AKL

kabel · 07-01-2009, 05:12 AM

The 225 up front is no problem, many of us are running that combination.
I feel it actually cures a bit of the understeer the car can exhibit.

A couple previous discussions on the subject:

No more PS2 205/50ZR17???
No more PS2 205/50ZR17???

215 or 225 tires in front?
215 or 225 tires in front?

Adam · 07-01-2009, 05:24 AM

Kabel, I think he was asking about the rear tires. Allen, why so narrow in the back? Snow? Cost? The 45 will have a slighty more sidewall than the 40. It shouldn't be an issue.

Lil bastard · 07-01-2009, 07:25 AM

You will not have any issue. The difference in aspect ratio (% of Tire width) from a 40 series to a 45 series amounts to less than half an inch in sidewall height - 0.452" to be precise.

It may have a different feel in real high G maneuvering (not necessarily bad, just different) but I doubt you'd notice it on the street.

To keep the same sidewall height (approx), you'd have to drop to a 195 tread width and that would adversely affect the car's handling and feel.

kabel · 07-01-2009, 08:59 AM

Ah, ooops. Sorry about that.