I just went from a 245/50/16 all around the car to, 245/40/17 in the front and 275/40/17 in the back. Will my car be slower? I don't think so, but I was just wondering. I think the new rims I got are lighter also. I went from salad shooters to 02 SS rims. (the 10 spoke) Thanks for the help

 

maybe a few hundreths, unless you needed the extra traction of the 275 REALLY badly

 

Well, I used to have 245/50/16 new street tires on it and I spun like crazy. I ended up putting my old drag radials on it and it was nice, but stil spun slightly. I haven't ran at the track with these tires yet, but I couldn't imagine it hurting me too much. It wouldn't make me go like a tenth slower or anything, would it? Because that is kind of a lot, you know?

 

when i went from a 275/40/17 to a 315/35/17 i lost almost 1 full mph..... thats when my car was bone stock.....

 

Well, that's a pretty big difference. I just looked up the rim weight and the SS rims are lighter. So, everything should be fine.

If anyone has time, take a look at my other thread. The moroso fitting one. I have some questions in there. Thanks for everyones help.

 

i didnt notice anything besides better traction.

 

yes it can be slower, it requires more work to get the car moving. think about a mountaine bike and a race bike (like lance armstrong, super skinny tires) which one requires less energy to get to the same speed? the one with the thinner tires takes less energy. i experienced this with my dakota, last summer i had 285 40 17s and 245 55 17s front and the traction was good, however i could feel the truck trying to move those wide tires up the road. then for winter i put in 215 70 15s all around and the truck moved like a hot knife thru butter. also my mpg increased nicely. so u have to look at the positive and negative, better traction, better stance, but slightly slower and a drag on mpg.

 

just get some slicks and say **** it!

 

Rear tire diamiter is almost exactly the same. The only real difference that you would see is in weight. if your that worried about it get a set of racing wheels for the track.

 

Most people forget that when you add weight to something that rotates it is effectivly heavier than just the static weight. Its called rotational weight.

Roughly its like 3 times the normal weight so if your rim and tire weigh approx. 45 pounds (1 tire 1 rim) then effectivly as far as performance it is like 135 pounds.

Hence lighter rims and less tires make you go faster, less weight you need to get rolling.