Auburn posi ???'s...please help

[dragstang86]

my car had a Auburn posi with 373 gears in it when i bought it. I can get the posi to kick in though. When i do a burnout only the pass. side tire spins. Ive heard with some posi rears you have to put it in reverse then back in first and punch it to engage the posi. Is that true with auburn? Im not very knowledgable about posi because all my cars have always had a locked diff. (but they wernt street cars so...) If i could get the posi to kick in i could really get some good 60ft's but right now i cant even come up on my 3500 stall or i wll fry the one tire. From an idle it still spins some and i has a 1.75 60ft. So i should be in the 1.60's if i can get this straightened out.

Thanks for your help,
bryan
90lx
86 coupe