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.

I am new here and accidentally posted this under truck appearance SORRY

 

Big difference. My 20's only weigh 61 and I can tell a big diff.

 

Well each pound you add on a whell is like 5 pounds of deadweight you add to your truck so you basically just added 560 pounds or about .5 secs.

 

Thanx redaddiction I am in the process of getting a g-tech to test it but your theory make a lot of sense. I am hoping I can stay in da 15s with my 20s on.

 

Are you serious? That much? Or are you embellishing?

 

i heard it was 2:1 not 5:1 but i may not be right

 

Thats a little embelishing. Truckin magazine did some testing and found that for every 10lb of increase for rims and tires at the same diameter of the stock rims, uses 5.5 to 7.5hp through the rpm range. Just like adding pulleys that give you a gain from idle to redline, it is the same kind of loss with rims and tires. That is why it is so noticable, even though you may only loose 6hp. So if the stockers were 42lbs, and the aftermarket were 70, then you may have lost up to a true 20hp, which would knock you down about .2 to .3 seconds in the quarter. What tires did you have. I weighed my rims and tires, 255/70/16s on polished GMC six stars, and they were 58.5lbs a piece. My new Stingray 20's with 275/45/20s are 61lbs a piece. I could barely feel a difference, but then again, that is why I chose the Centerline lightweight rims, and that is what everyone here recommended I do.

 

What rims are these that you are talkig about? I have heard centerline are one the lightest rims and do not affect performance with the GYGTII 275/45/20 tire.

 

i have lost approx 3 to 4 tenths of a second.

 

I have seen same results 3/10. I havn't run them since the tranny build or stall.
I run stock wheels up front with 215/70-16
and 28/11.50-16 in the rear. Both 28" tall.

All the stock wheels I've measured have been around 50-55lbs with varoius size tires so I'm anxious to what stock setup your talking about. Even the 215/70 which are quit a bit smaller than the stock-235/75, tip the scales at 48-49lbs on rims.