A Ladder Bar Hole Tuning/Adjustment

[CraigG]

72 GTO.

Car launches straight, carries the wheels But now has a traction issue:
Initial hit and spins recovers 10 feet out with loss of .08 to .1 at 60 foot with 3500 launch on 2 step on 5000 convertor

New best with a 6.41 at 105.5 and later spun at 106.

That was an improvement of over 4 mph when I ran a 6.58 at 101.8 from a carb tune, slight port match and a change from 3.73's to 4.11.

Still launching at 3,500 - 2-step with 5,000 still to grab.
Turbo 400 4.11 Pro gears with MT 10.5w x 28 slicks

Front suspension:
QA1 Pro Coil Double Adjustable GM coil over conversion system with 350 # springs
Adjusted to 90/10 settings
Low friction control arm bushings and ball joints
Total Race Weight 3440
Front weight 1860
Rear weight 1580
Percentage Basis Front to rear 55% to 45%

Rear suspension:
Full length Competition engineering adjustable ladder bars
Bottom hole lowest front heim end setting
Right bar - slight preload
“5 #150 (?) lbs - springs with spring jacks
Stock Mount: 28 year old Koni single adjustable set at 1 turn tight from lightest setting=Issue(?)
Pinion angle 2 degrees negative
MT 10.5w x 28 slicks with tubes at 14 pds cold - best runs

Thanks Guys, Craig