Engine/Transmission (1998.5 - 2002) Boost Question/How much PSI is OK?

[kebees4]

I have a question concerning boost pressure. When truck was stock I could only hit 20-21PSI.

Then I lost muffler changed to straight pipe and boost went to 22-23 PSI.

Then I added EZ and it went to 24-26 PSI.

Then I changed lift pump (pressure low) and changed to synthetic oil at same time. The weather also went to 80 degrees F. and now I can hit 30-31 PSI boost.

Is something going wrong or is this normal to see this much increase. When will boost pressure start setting codes?

I am curious why pressure increased recently.

 

[cumminspwr01]

I think you would usually see a code near 23 or 24lbs my truck stock minus the muffler & resonator also made 23lbs but as long as you have that box on there it should never set an overboost code thats what the box does

 

[kebees4]

I am glad to hear it is not going to set a code. I am planning a trip in 3 weeks and don't need any problems while in Canada. Thanks for the input. Do you think these are normal pressures?

 

[Tcolesanti]

Very normal, my buddy has an '01 and his pushed 21-22 stock.

 

[kebees4]

It just started hitting 30 PSI recently and the only change was weather, oil, and lift pump pressure. Somewhere in those 3 changes is when it took a big increase from 24-25 range to 30- 31. I just doesn't understand why it suddenly increased.

 

[GIT-R-DONE]

My 02 stock would hit 21 lb. of boost. With the addition of the EZ, I now hit 34-35 boost. That is max WOT. Why the increase, I don't understand either, but I would have thought you should have seen it all at once with the EZ installed.

 

[24V-DSL]

IMO, at 30 psi you're right at the limit of efficiency for your HY35/9 turbo.