they say ever 100 lbs' is a 10'th, and those rims are about 20-25 each, so if you get some light ones, i am guessing about 1/10'th faster at best with lighter rotating mass, but i cant be sure
That's unsprung weight - it makes a much bigger difference than simply lightening the body or whatnot. Weld Draglites are very light and strong, and you will gain somewhat with them, at least a tenth if not more. There is a rule of thumb for unsprung weight to sprung weight comparison.
I don't remember what magazine it was but there was a comparison test on a Chevelle. It was the stock steel rims vs. other lighter alloy rims (don't remember the brands) and the overall conclusion was it shaved as much as .1 sec off of the Chevelle's ET.
GN-
you're right, there was a test in a magazine. it was Car Craft that ran it. the results were that it shaved off around 18-25 ?pounds and improved the ET by one tenth. my 2 pennys...