Well i havea 94Z,, with subframe connectors..panhardbar...i just installed Zr1 wheels with 275 40's on then...now i raced my friend the other night and at around 110-115 the rear felt like it was shakin from left to right..i know the tires arent the greatest.. sumitumo cheapies offa tire rack..just wondering if that could b the cause..or the extra rims size and tire size could effect this..if so what could i do to eliminate it..thanks

 

Take the wheels off and check the balance. There was another guy on here that raced after getting new tires mounted and the tires ended up spinning on the rim because of the grease they put on when mounting the tires, thats what threw off the ballance.

 

110 is against the law there sonny boy. definately the tires. if you're going to be hitting over 100 often, makre sure they balance them to excacts. most specs allow for one side of the wheel to be a 1/4 ounce off since you'd never feel that going anything under 110

 

Are you sure the rear wheels seated fully on the hubs? Sometimes you run into a problem fitting the newer model wheels over the over-size rear hubs on the earlier year 4th Gens. That would explain a side-to-side wobble.

If they aren't seated all the way, you might have to enlarge the center holes in the wheels slightly.

 

Well i mounted and balance them myself (i work at a chevy dealership)...so i know the balance is good...i know i didnt buy the best tires...ill take em off and check the balance...thanks for the Info guys..so no upgraded sway bar or bushings r needed right away?..thanks again for the help