Suspension 90 GT help with launch

went to the T&T on wed night and got the GT to the track after 6 years.

My mph was indicative of my combo but my launch needs work

1.822 60' and a 12.67 et at 111.44 mph

team z street beast kit with relocated uppers, stock strings, strange 10 way single adj all around

front shocks set at 3 front full loose and rears are 5

launch at 4000 rpm, tires are et street r bias at 16 psi shift at 6000 rpm

combo is 347 trick flow top end kit with larger comp cam, full 3" exhaust x pipe mac dumps, 369 hp at tire

weighs about 3350 with me in it. estimated, no spare no rear seat, smog removed, basic weight reduction

front rises a bit, settle down good, but rear bounces in first gear, not tire hop or wheel spin

should i tighten the rear springs?!?!

video to follow:

View: https://youtu.be/RlSy51iN92k


thanks

It does sound like a bog, i'll raise it up to 5k and see where it falls

thanks for the input

also nice car, great passes too!