I have a hotcam and Ported exhaust ports on my LT4 heads. Is there something to look for? Thats a lot of HP missing.

 

Did you check your belt to see if its on snug?

Either way That kinda sounds right to me.

I have a cc305 cam, long tube headers, a low comp 383, STOCK heads....And I am running a 15# pulley (for a stock motor) and I only see 10psi of boost at 5800rpms.

Thx,
Claude

 

I hear what you are saying.
Last year I had the 8# pulley with untouched heads and smaller head gasket and saw 6#

This year I had the exhaust ports done, along with the chambers to open up the CC's, along with a stock thickness gasket. IS porting where all my boost went?

 

The following will attribute to lost in boost:

-Belt Slippage
-Ported heads
-Increasing Bore in block
-Bigger exhaust port headers
-Inefficient intercooler
-vaccumm leak

 

altitude has a lot to do with it to: in sacramento only 25 feet abouve sea leval, my car makes 17lbs in las vegas 2200 feet i see 15lbs and in albuquerque 5600 feet i only see 11lbs.