moving backwards

since i built my 393 i installed a roll cage upper and lower control arms with polly bushings and a anti roll bar , my car doesnt twist and deflect near as bad but the upgrades are stoping my weight transfer it seems the car is too rigid and doesnt rock back as well

i dont have the sway bar in the front and i have 90 10s in the front , im still using stock springs and shocks in the rear , I use 27 inch hoosier quicktime pros

I am planning on getting softer springs on i hope this will get it transfering good again

has anyone had this problem?

When you installed the bars and roll control were you checking that you maintained the pinion degrees? Also when you have the Hoosiers on how much did it raise the back of your car? The rearend isnt going to squat much because of the action of the 4 link pushing the center of the car upwards at its instant center. This upward push is pretty much rendering the springs as being ride alongs during that first hit because the car is doing what we call "on the bars".
Other thing is urethane is really stiff so if you put your new bars on the car with the rearend hanging and not at ride height they may be binding.
So with the car jacked up loosen the bolts and then sit the car on the ground and re tighten them. This will help free them up at rest. Also on the roll stop bar, did you preload it with you in the drivers seat? If not you need to loosen the lock nuts, find the same weight as you or a person the same and have them sit in the seat.
Now crawl under the car and be sure both links are free without tension with the weight in there. If not turn the left link untill they both swivel freely. This gets you really close and is a great tuning device as well.