boost gauge levels

[classic69]

ok so i finally bought an aftermarket boost gauge today and took car for a spin the gauge reads 20-22 vacuum at idle and goes up to max 10 at full boost then drop off to about 5 ?!??? thats not very good i dont see any major boost leaks on my setup ill test it tomorrow . i tapped the gauge at the fuel pressure solenoid so im guessing the numbers are right? 5 psi is like really bad if it was a boost leak wouldnt it still go up higher than that? btw when im cruising at 55 on highway at 3K boost gauge reads 0

 

[doug]

The vacuum numbers seem right, but since the boost numbers seem low, I'd recommend doing a boost leak test.

 

[classic69]

yea i did a boost leak test MAJOR leakage around the Jpipe gasket , any suggestions on what to use to seal it up the flange is like warped so it doesn seal good even with gasket, i was thinking copper rtv?? its right next to exaust runner too...

 

[doug]

RTV is probably your best bet, although if it's warped as bad as you say, you may want to consider a new J-pipe.

 

[ADrewzki]

I'm going to say get a new j-pipe. The turbo gets pretty hot and, while some RTV is good up to 500*, it's just not something I'd want to have to do over and over again.