ss springs shocks

I'm using kyb gas shocks on my 68 cuda with no problem but also b body shocks are about 2.5 to 3 inches longer than a body shox (for future reference)
are you using a pinion snubber ? I'm set up with 3000# super stock springs with the KYB with coil over springs and an adjustable pinion snubber and I launch at 5-6000 rpm straight and true and Hard. Running 8 psi in my tires and usually can carry the front off the line