So I got the cap from someone local and put It on my car today and took It down to have It tuned today. I finnaly broke 500hp(509hp 373troque). I was runing 19 pounds of boost and It would drop off to 17 pounds @ redline. I couldnt figure out what was making It drop. Is there anyone who has had this happen to them? any sugestions?

Setup:
6262 turbo
tial 50mm bov
tial 44mm wastgate
precision 750 intercooler
sidewinder mani
id 1000cc injectors
aem 1052
tru boost boost controller
inlinepro fuel rail
3in from the turbo back megan single
3bar gm map sensor
walbro 255
2.5" to 3" intercooler piping and no leaks

Thanks for any help

 

Where is your duty percentage set on the boost controller solenoid? You may just need to up the percentage closer to 80-90% and see if that does anything.

That turbo isnt even breathing so it definitely shouldnt be dropping boost at the top at 19 psi.

 

Its that wimpy Turbo. You need a gigantic t25!!! JK JK.

 

I will check that and get back with the results.

 

Any other ideas?

 

Whats the A/R on the turbine housing? and what wastegate spring?

 

maybe downpipe too small?. maybe you can try taking out the catback really quick and log your boost. im sure you have no cats on that beast.

 

It has a 82 A/R and Im using a 15 pound wasgate spring.

 

Im running a 3" dp so I dont think thats the proplem.

 

So, upping the duty percentage on the boost solenoid to help hold the boost better didnt work?

This is very odd.........

I wonder if its a bad GM map sensor? I've heard of them going bad and causing problems but I dont know if it would cause this problem youre having.