Why can't I get more than 38psi of boost? Look at my sig and I have more than enough performance parts to make over 50psi boost but truck stops at 38. I can't find any leaks at all and I am sure the turbo is installed right this time. Rail pressure is staying above 20,000 psi at WOT so what can be the problem? It's a mechanical wastegate and I have the adjustment screw all the way in so it should be disabled. Can the computer be defueling the engine if the boost fooler is not working right? Thanks, Tom J.

 

Well I think it might be because the computer is dumping the extra boost by opening the wastegate. I read somewhere that even with a boost fooler on there is still a manual dump that happens. I am sure those who play with such things will tell you more.

 

The Smarty and injectors alone should provide enough drive pressure to send that thing through the roof! Ok, at least 50psi...

Seriously, try manually disabling the wastegate altogether or safety wire it in the closed position instead of fooling with the screw. Try that and see what happens. Turn your quad down to level one to do this. (Don't want to pop you HG... be careful!)

Report back and we can go from there.

 

Ive got the exact same problem with my superb turbo,wont boost past 35psi,pinched off the tube to the waste gate ,nothing.

someone mentioned to me that the commander only reads to 38psi so i put a temporary manual gage it reads exactly the same maybe +-1psi

 

check your codes an overboost code wont throw a light but it will defuel