Scaling a stock suspension car.

I tried to duplicate a SS spring set up. with adding some spring to car. 7 right and 5 left.
didn't have enough power to have made a difference any ways. Every one says the SS springs made the car ride stiff.
When i went to SS spring i thought i had a Cadillac. That was how stiff i made the rear suspension.

Have you taken it to the track? does it try to steer you one way or another at launch?