Already have some good advice from these guys but i'll just add that i agree with tech1 on the 150# springs. I have a tube chassis car with coil overs i'm building and i dont quite know the exact wieght of the car since it's no where near stock but i went with 150# springs as a starting point as have alot of other guys i know and the 150's will get you in the ball park ...so ta speak.

Plus if you do drop down to say 100# springs its alway good to have a couple sets of different rate springs to experiment at different tracks.

BG