Alot more than the stock injectors can push. I was running mine up around 20psi and tappering off to around 16 or so and that was with upgraded injectors. You also don't need to add boost for things to break. Russ
Word. It would be easy to break stuff at the stock boost settings, heheheh. Let's see....13.5:1 afrs and oh about 30* of timing around peak torque. And oh yeah, a tank full of 87. lol.