Accuracy of Stuart Warner boost gauge?

[BlueByYou2000]

On my CPR Apex, boost shows 7 on a 30# gauge. I shortened the actuater rod appx 4.5 threads, sled definetely pulled harder but gauge still reads 7. I talked to Jeff at CPR and he says the 30# gauges are 1.5 to 2 lbs off at boost reading under 15. Anyone have input here? My A/F gauge has the same readings before and after I shortened the rod. Wouldnt raising boost without adding fuel show higher A/F readings?

 

[gsxr]

Are you reading boost before , in , or after the intercooler?

 

[BlueByYou2000]

In the intercooler

 

[gsxr]

Why not read between the throttle bodies and the engine ,I would think it would be more accurate as to what the engine really see's.
my MPI does , unless turbo set up is different.

 

[lakercr]

In the intercooler

Matt, I think you mean you're reading boost in the intake manifold (before the throttle plate), as opposed to after the throttle plates? If that's the case, you're gauge will read a bit higher at most throttle settings than what the engine is actually seeing. WOT should be about the same.

It sure sounds like your gauge is not giving an accurate reading. Try to find a stand alone shop gauge that you can 'T' your boost gauge into. I have one that I use for setting wastegates on the bench. It is very accurate, and wasn't too expensive. you should be able to cross reference the sled's gauge to the shop gauge and see how far you are out at different boost levels.

The long term solution is to get a more acccurate boost gauge.

 

[rxrider]

BBY2000 - it's time buying a boost controller

I did the same as lakercr says last year. I didn't thrust my Autometer and hooked up a shop type meter reading BAR and cross referenced it to the Autometers lbs readings. The Autometer was spot on to my relief, I suspected the Autometer to read too low, not a good thing.