At some point I was thinking about getting new wheels to replace the 15" steelies on there now, but I don't want to sacrifice much if any acceleration. Would there be that large of an effect to go to lightweight 17" rims that weigh 15-20 lbs, as opposed to my steels that weight ~45? If so, what about 16" instead? Just wondering how much the rotational mass increase will hurt acceleration...

 

it will help it as long as the overall diameter of the tire is equal.

 

Depends on where the mass is. I had 3rd gen SE rims/tires for a while (stock stealies were bald). Then I got 18" rota subzeros w/tires. I put them both on a digital scale and they weigh the same. however, the 18" definitely slowed my straightline acceleration. the 18" rim itself was 17lb, but w/the tire on it just sucks.

Jae

 

sorry to **** your thread but i got 17s silver and it didnt slow me down, but i wam wondering if 18s chrome would?

 

sawblades only weigh 16.5 lbs...

 

really?? I don't know where I read that they were 40+ lbs. but I guess you can't believe everything you read. thanks

 

They are closer to 40lb w/the tires.

Jae

 

It depends on how much rotational inertia the wheels/tires have...which is dependent on not only the mass of the wheel/tire combo, but how far out from the center of the rim.

As a rule of thumb, each pound of weight on your wheels will affect your car like four pounds on the chassis, (from an acceleration/braking standpoint and assuming the moment of interia is the same from each combo)

For instance, I put Fikse FM10s (17 lbs each)on my '98 Camaro, then I put rear 275/40/17 out back (31 lbs each), and 255/40/17 up front (26 lbs each). These replaced my stock rims (26 lbs each) and original tires (31 lbs each). My total rotating mass was reduced by 46 lbs, which will seem like [about] 184 lbs on the chassis. It was like NOT having one of your buds in the car. Also, the suspension carries less inertia, so it can react quicker, thus improving your handling AND ride.

Good luck--Justin