ok.. I know you said acceleration, but I thought it might be nice to mention that braking will be affected too.. more weight to slow down..

I heard that every 1lbs. unsprung weight you lose is equal to 4lbs. sprung weight, in terms of acceleration. Also, the heavier the wheel, the more work the suspension has to do. You just have to weigh(pun intended) your options. Are you willing to take the added weight in exchange for wider tires/stiffer sidewalls?