Mine 91 Camaro is peg leggin on burnouts. I'm only getting one tire spinning. When I just step on the gas no break, they both go. My friend was teling me something about how I might have what they did when you apply the break, where the stall speed converter cuts out and ****. I don't know. Is this normal or is my posi going? Doing a donut it worked as well.

 

Simple answer, your car was made without option RPO G80 or a LIMITED SLIP rear.