Originally Posted by Fishey

Depends, stock bars with stock bushings can effect strait line performance.

The reason, The factory bushings are rubber that bind when moved from there settled position meaning that even unattached they will want to return to the position they were tightened. So as a result they tend to act as additional spring rate (ever so slightly) and will reduce weight transfer onto the rear axle. If you have aftermarket poly bushings with lube they will move freely no bind = no problem.

-Ron