not much but enough the corvette tranny really helps the car go but its under rated at 275 most get like 285 or so. enough that no matter what bolt ons mustangs got they lose in the end. and most other trans ams and camaros.

 

that is fast i have afriend that has a builded 383 in a 66 nova and is running in the 11--i going to past on your email to him since your running that fast with a stock motor maybe he is doing something wrong