Need some help here

[acerasuolo]

Hey guys, i finally got my car back and got her on the dyno. its been a long 2 days, drove from ventura ca to anahiem, got a break in tune, then drove another 300 miles that night to break the clutch and motor in some more so that i could get another tune the next day. well this is my graph. put down 433rwhp 420rwtq

i need help to figure out exactly what is wrong. the possibilities that i see are

not enough fuel - from the pump
belt slip
bypass valve opening too early or not holding boost

both pulls only yeilded 6lbs of boost with a 3.12" pulley on a vortech t-trim at ~5500 rpms. any help would be great guys.

ps.

are the the numbers are pretty good at only 5500?

 

[LOVESBOOST]

looks like possible slip in the upper range, the ones I have seen are either jagged, or fall straight off, and yours falls off.

You can also look for a vacuum leak.

 

[acerasuolo]

yea i was thinking that the bypass valve was releasing the boost. i hope this isn't going to be a long drawn out fix. my redline is at 6800 so i think it should at least be in the 525 range

 

[acerasuolo]

anyone?

 

[01yellercobra]

Check around the blower pulley for black dust. That will tell you if you have belt slip. What bypass are you using? Maybe you can swap with someone that has a good one to see if that's the problem. Although I would think the boost would keep it closed anyway.