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xmac
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Posts posted by xmac
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Ok I am going to take a little different approach here. The sizes you are running are not stock to begin with. With 18" wheels the OEM sizes are and revs per miles are as follows (all this is based on PS2's but this info is available for most tires on Tirerack.com). 225/40-18 are 829 and 265/35-18 are 822, so the fronts rev 7 more revolutions per miles or .8%. The PS2 is not made in a 285/30-18 but the 295/30-18 is 832, so the front revolve -3 or .4%. obviously the 285/30-18 would be smaller but I am not sure how much. The 285/35-18 is not made in the PS2.
I have run 235/40-18 fronts at 819 and 265/40-18 at 790 for several years with no problems. These are a difference of 29 revs per mile or 3.5%.
When you are evaluating these tires you should really look at the size/revs per mile and stay as close to the original as possible, although I have been told that 5% or less is OK. I know that starting in year 2002 (I think) the rears were changed to 285/30-18. I don't know if the PSM or the ABS computers were reprogrammed at that time.
By the way the Conti Sport Contact2 seems to be available in 295/30-18 at 827 revs with the 225/40-18 at 825 revs, so only 2 revs per mile different. But they are also much more expensive than the DW's.
Hope this may be helpful.
Dharn55,
Thanks for the help and noting the 295's are actually a closer in revs. I too have a 99 C4 and am in the exact same situation. Unfortunately in my case, I hit something on the freeway which damaged one of my rear tires and the fronts are in need of replacement. I too was looking at the Extreme DW's but they are on backorder. I am considering the Sumitomo HTRZ III's since these would be for daily driving.
Changing Tire Aspect Ratio
in 996 Series (Carrera, Carrera 4, Carrera 4S, Targa)
Posted
I just got off the phone with a rep from Discount Tire. He said the front (225's) are at least 45 days from coming in and the rear (285's) are indefinite. He said the tires are made in Portugal and they are having difficulties in producing enough tires or maybe they are not producing those sizes right now??
In any case, it looks like I need to pick another tire or park the car.