[n20ta2]

I just installed a leed black bandit vacuum pump for the power brakes on my 69 gto. It holds vacuum well but I really dont have good brakes even with the pump. The complete system is new and completely stock including all lines rubber hoses ,calipers and rear wheel cylinders. I did install an 8" booster in place of the stock one for more clearance for the highports, could the booster be the issue? It almost feels like non power breaks at this point. I also used a new stock replacement perportioning valve from inline tube.