I got a question for whoever can offer some advice. I got a 420 small block chevy that has custom Ross pistons for a 9.0 compression with a 0 deck height and a .039" head gasket. I got a 400 block with a 4.155 bore and a 3.875 stroke crank and 6.0 rods. I just aquired the blower off EBAY and just in time because my pistons were ordered two days before for 10:1 compression. No refund or exchange on custom $800 pistons. Now that I'm trying to tune this blower, I don't want to over do it. I have about 5-6 lbs boost when I first get on it but after about 4500 rpm my boost is falling to about 3-4 lbs. Should I adjust this setup to provide six pounds on the top side or leave it at the bottom side At cruise it has low boost which I was told is good because you dont need any boost under about 2000 rpm. This motor is built to shift a 6500 with a 7200 redline. Also this motor is topped with 215cc iron eagles, solid roller comp cam custom grind .590in. .608ex. lift and 248in. 258ex. duration@.050 tappet lift with a 112 lobe centerline. And last of all a Proform 850 double pumper. This motor runs hard but that boost loss at high rpm is troubling me. I think if I build the boost a little higher at first it could sustain 5-6lbs up high. But don't want to fry it.



Thanks, Ray