Hey all...this may sound silly but laugh if you must

...
ive got an 88 tbird sport...5.0(std no HO) auto and 7.5" traclok...not really racing it at the time but looking to practice and have a little fun =)
the traclok does work as far as i know...i leave two marks no matter what surface im on if i just hammer it from a stop or slow roll...but if i try power braking only one tire spins while the other catches around 5 seconds later...could this be my brakes?...or is it the rear?...any tips on how to power brake more sucessfully...i have only gotten the tires to actually bake twice while power braking and it was only one tire then the other caught on for a few secs...all of the other times either they both spin(they dont bake just spin for a few feet) as if i wasnt even power braking and grip and i take off or they both chirp for a fraction of a second and then i barely move...i dunno...
-james