I was messing around outside and decided to weight the wheels and tires of my truck and this is what i found out.

Centerline Stingrays III 20" with Cooper 275/45/20 = 70.5 lb

Stock GMC 16" with stock 255/70/16 tire = 56.5

Stcok iron spare rim with 255/70/16 = 64

The scale seem to be pretty acurate since all my 45 pound barbell plates came in at 46 lb.

I did not know my 20 were slowing me down that much. According to my brother in law who holds a Master in Mechanical Engineering, for every 1 pound you add to the wheels, it's like adding 4 pounds to the overall weight of the vehicle. He actually came up with an answer of 3.89XX. This figuire only hold true if tire/wheel combo weight distribution is the same. If the weight of the wheel in respect to the one being compared is more towards the middle, then the it would < ~ 4. If the weight of the wheel is more towords the outside, then it would be > ~ 4.

This being true, I am carrying ((70.5 - 56.5) X 4) X 4 = 224 pounds more with my 20's in place of my stock tires. This equates to ~.2 slower on the .25

 

yeah what he said.
basically in a nut shell for those with large (overall) diameter rims and tires. you will be a few tenths slower than some one with the SAME mods, and smaller diameter rims and tires

 

Cool! I'll update the wheel/tire weight thread.