Car Bounces after 60 ft. What is causing this??

I had a 63 Fury drag car that was green,got the nickname Frog because it would hop like that. Went to taller front tires and loosened the T-bars(Big block with slant 6 bars) solved my problem. Maybe? just a thought..
Sounds like a good idea. I thought it would be better to have the car level after getting taller back tires, but cranking up on the t bars looks like it was not the way to do that....Will loosen the t bars.