Low boost on a 2000

[drdiesel12v]

my buddy has a 2000 24v, 240hp injectors, silver bullet 66, hrvp44, edge drag comp, air dog 150.

the truck use to make over 50psi with that combo when the previous owner had it. it now makes a max of 40psi. my buddy has blown a head gasket, had alot of material removed (not sure how much but machinist said not enough to cut again) and installed a stock thickness head gasket back in. didnt change injector washers and i would imagine also raised compression a pretty fair amount.

truck throws no codes and has fuel pressure like normal. when at WOT w/boost the truck clears up, no smoke.

im not sure what could be wrong with it, any ideas or suggestions would be great

thanks
Cody

 

[drdiesel12v]

Well we tried something. He unplugged the map sensor but left edge comp hooked up to the harness. Miraculously, 48psi of boost and more power. Does this mean map sensor is bad?

 

[kino_fab]

could be the culprit.

Although correction on you compression being higher.... Shaving the head on these engine will not raise the compression much if any. The head is flat to begin with and the fuel bowl size of the piston is what can change the compression ratio (on a stock bore and stroke engine). Its not like a gasser engine where shaving the head lowers the combustion chamber size in turn raising compression. Think of the fuel bowl on the piston being the actual combustion chamber in this instance.