Short Inquiry, while I'm waiting for my new Rims to arrive, I had the tire shop put on new tires on my stock rims; I went with 245/40/18. These will also be the tires I'll be using at the Tracks. However, I noticed that the tire shop accidently put on 245/45/18. When I called back, he apologized for the mistake and gave me another 25% discount. I should of asked him to take it back, but I took discount instead, figures it's only temporay for a month, and I'll using them on track. Normally I'll run my 19's.

Anyway, enough being stupid. I check the tire calculator, and it said my new tires are 2.67% bigger than stock. Aside from the speedometer being off by 1.6 miles slower, the side walls is 0.36" higher, and overall diameter is 0.71" greater.

Would this difference have a big affect on the handling and braking? Or am I screwed?

BTW, the tire calculater said when changing tires and rims, to stay within 3% (+) or (-) of the original size.

Your feedbacks would be appreciated. Thanks!

 

Off hand I 'd say you may improve handling a bit, perhaps bit smoother and more stable, at the expense of acceleration/braking due to the extra unsprung size and weight and rotational inertia. In reality it may not amount to much noticeable on the street, maybe more at track. Still, nice discount you got!

 

i think you really wanted 245/40/18. i will get that size in toyo's when i burn the stock ones off. i will gain no weight, just friction.

 

You will give away some sidewall stiffness because of the increased sidewall & height, but in return you will get a bit more compliant ride. As long as you have the stock rims you are OK, in that you will not have any rubbing problems.

 

Thanks for the feedback guys =)