How much difference in track times is there between 20 inch wheels weighing in at 70 pounds and stock wheels weighing in at 42 pounds. The 20s have a 265/50/20 toyo proxes st and the stocks are 235/70/16 firestones
I have talked to ppl who say there is no difference as long as the overall tire size remains the same

 

Sorry I meant to put this under truck performance

 

First off, those people are WRONG. Wheel weight has a big effect on power. OD has nothing to do with it in your case. When you cange OD, you are changing the gear ratio vs stock. Your looking at over 100# different with the wheel you speak of. A good rule of thumb is for every 100#, you gain or loose a 10th. There is another formula for wheel mass and how it effects the parisitic loss, but I don't remember it right off hand.

BTW, I'll move this back to the performance section for you.

 

I can tell you this much from my own experience. I have a 2000 ECSB with a HPP3 and a magnaflow catback. My truck with stock wheels is .2 to .25 (tenths) quicker than with the 20's. I have the centerline lexi IV's w/ 285/50/20. They are a bit taller, so that explains some of it. My best time with stock wheels was 15.20, and my best time with the Centerlines was 15.43. Hope this helps.

 

Well, you are going to be slower w/ the 20s than the stockers. Now, if the overall size of each was the same, AS WELL AS, the weight, you probably wouldnt see any major difference, but being most 20s arent lightweight wheels, there is going to take a lil bit of power away.

Personally, 20s look good and fill the wheel well up better, but i'd much rather stick w/ 18s. To me, they just look better. They've still got that shine to 'em, but i just dont wanna be like everyone else sayin "hey man, check out my dubs"