Alright I'm boostin about 1psi too high according to my gauge, under WOT (13 psi for both first and second). I have a 3'' SS DP, M2 Cold Air Intake, and a 3'' Catback. (Yes - I understand that I'm on the edge with 3 air flow mods like this, and that the next thing I need to install is some sort of boost regulator).

I noticed tonight that my old *** boost gauge, when the car is turned off, is at about -1 to -1.5. Is it possible that the boost gauge isn't like... reading right? Sort of like how a weight scale can be 5 lbs too light because it starts at -5 lbs...

If this is possible, PLEASE let me know...

I have the money for the PFC now, but I would like to buy an A/F meter first, purchase the PFC commander with the PFC, and be able to pay for professional tuning once I get both installed.

 

It's a VDO boost gauge, if that makes any difference...

 

it is probally fine, your boost guage reads ambient pressure which is not ususally at 0

also, a/f meter is a waste of time unless yoru talking true, professionaly built wideband meter which should cost you about 1.2-1.5k

 

well if that gauge is reading ambient pressure, 13psi is all dependent on altitude and conditions IIRC. So depending on where you are, that could be anywhere from 8-16psi at sea level. A quick way to check is just get cheap new boost gauge that reads absolute pressure instead of ambient (i hope i just used the right terms ) and double check. Skunks is right...a/f gauges are total crap unless theyre calibrated for and hooked up to a true wideband.

-Zach

 

My boost gauge (autometer) has a box for the "0" instead of just a line. I assume it's for the reason that skunks described above. My needle is always way on the left side of the box (like almost in vacuum) when the engine is off, which sounds like what you're describing. AFAIK thats normal.