ic location

[joel]

hello,

i have a small chassis issue that i was hoping someone would have a little input on. when my car leaves it hangs the front wheels an equal 5-6" then when the weight comes back down it seems to lift weight off the rear, than the rear does a noticable bounce for a couple hundred feet. friends that watch the car leave say it looks like two long slow bouches. the car is a 69 chevelle with a 4-link chromoly backhalf, real 10 wide tire, 3300# w/ driver, 780h.p bbc, th400w/brake, tight 9" nos conv. the car is freshly constructed and set up for spray. car has two runs, 9.99 9.95 at a tick under 136mph. goes arrow straight and is easy to drive but, before i hose it i want to fix the bounce issue. i think the ic location is part of the problem but, i could use some outside opinions as my garage time is very limited these days so i want to get it right this time. the ic is 48" out and 4" up. thinking of going more like 42-44" 6-7 up. havnt figured out the cg yet as i dont have access to any scales.

thanks in advance, joel

[Jim Monson]

Sounds like you need to stffen the compression on the rear shocks. Do you have adjustable shocks?

[joel]

yes i do have single adjustable alden eagles. they were one click from being on the stiffest setting, i then went the other way and went one click from the softest setting. the softer setting seemed slightly better. is the ic in the ball park? i think the ic i chose might be more suited to a full tube car with a lower cg.


thanks, joel

[Jim Monson]

What rate rear springs?

[joel]

150# springs

[Monty Mikho]

Extend the IC to around 52-55" and 5.5-6" off the ground with a 1.5* down angle on the lower bar. Start out at 1/2 soft on the shocks and see what that does.