Maybe the brakes aren't strong enough. I don't have a brake pressure gauge. The starting line is alot different than your driveway. With my converter change I lowered my launch rpm from 3400 to 2700 and dropped front tire pressure 10 lbs. to cut a light. I have Wilwood discs up front and stock Ford drums on the rear.
Don't need no stinkin' transbrake.
Jeff