: Can I run a 27.1" tall tire? How about 26" tall?



nuck
08-21-12, 11:56 PM
Looking at a g-Force Sport COMP-2 tire in a 255ZR18 profile. These are almost 1/2" taller than stock. The slightly fatter 255/40ZR18 is .6" lower than stock. Will the height difference throw off the ABS or speedo? The 40 series is for a rim width range of 8.5-10" and a measured rim width of 9" according Tire Rack. Will I lose traction with this extra width on stock wheels? Mine is a blower car so I need all the stick I can get. Thanks for any responses.

odthetruth
08-22-12, 01:56 AM
I'm on 245 40 18s, which is an inch shorter then stock, with no ABS codes. You won't get a speedo code, but just remember it'll be off a tiny bit depending on what you change your stock size too, unless you can calibrate for it.

Andringa
08-22-12, 10:03 AM
I would think that you should be fine as long as all of the tires are consistent. The ABS/Stability system works on differential wheel speeds. i.e. if one wheel is significantly faster/slower than the others it will try to fix that. So a tall tire in front and a short one in the rear could cause the ABS computer to get different readings even though both wheels are traveling at the same speed.

If all the tires change, then they all report the same speed and the car can't tell the difference.

GDPossehl
08-22-12, 11:16 AM
I've been using this tire size calculator for years:
http://www.miata.net/garage/tirecalc.html

As long as you keep the fronts and the rears at 2% difference or less, you should be fine.

carlson_mn
08-22-12, 11:10 PM
With a blower I'd think you'd certainly want a taller tire. I think 1st gear is overly short as-is on a stock car. Go for the taller tire. Will fill in some of the wheel well gap as well.

nuck
08-22-12, 11:52 PM
Thanks guys,and Carlson, I should have thought of the height thing myself. Will definitely not go smaller diameter. I see some guys are actually running 275 40 on stock wheels which have a huge footprint (10.7" depending on manufacturer) and stock height. I think with a slight drop in tire pressure on saturday nights this might be the one for me, if I get one of the better dry traction tires.

thebigjimsho
08-23-12, 03:27 PM
With a blower I'd think you'd certainly want a taller tire. I think 1st gear is overly short as-is on a stock car. Go for the taller tire. Will fill in some of the wheel well gap as well.

And rip out your inner fender liner if you drive aggressively...