The recaps you have, are "show car" tires and not really designed for drag racing. If you go to a real drag slick or a DOT drag slick you will notice a big difference in traction. Caldwell Tires in Pasadena used to be the place to buy recap slicks in the Los Angeles area years ago, but they are now gone.

We have had great racing success with M&H tires. They are sensitive to air pressure changes and need a good burnout before going to the line. We run our slicks tubeless and you will be surprised how much lighter they will be than your recap tires when installed. Just call the national M&H distributor Hashim's in Bakersfield, CA and ask for John Hashim. Nobody knows more than John who has been in the game a long time. Tell him The Palmer's VW team recommended you.

I also agree that putting more spring weight on the right rear will help out on our launch with an open diferential. Maybe look into a stiffer rate coil spring on that corner if running a coilover four bar set up? I always felt that if you could set-up the car to launch well with a open differential (by correcting corner weight), then going to a limited slip would be the best set-up.