i know this question has probably been asked a million times...but what is the PSI conversion of the stock T2 boost guage. i've been told that if the needle goes to the top (45mmhg) that its about 12PSI???

 

I've been wondering that myself. I was having problems with the guage for a while now it seems to work fine today. I was floored in 4th on an onramp and I noticed the needle was in the middle to top section of the FULL-size orange block 2nd from the top.

So, anyone, what psi would that represent? 8?

'90 GT-X

 

the TOP is 12psi i think....

 

on my boost controller instructionsn 500 mmhg = 7.25 psi
so 700 mmhg = 10.5 psi
and 950 = 14.25
hope that helps

 

The boost guage reads out in units of millimeters of mercury. We like to see our pressure readout in psi (pounds/square inch). The conversion factor is .1934. Crunching thru the figures, we get:
5 = 1.0 psi
10 = 1.9 psi
15 = 2.9 psi
20 = 3.9 psi
25 = 4.8 psi
30 = 5.8 psi
35 = 6.8 psi
40 = 7.7 psi
On my boost guage (when the fool thing decides not to stick at -20!), I get a reading (max) of 35 in first and second, with it creeping up to 40 in third. I put a boost test guage on the car, and it read 7.0 psi in first and second, and a little over 7.5 in third. So, you see, it corresponds very well.

Irv, Keith's dad

 

when i'm boosting 10 psi on my after market guage, my boost controller which reads in kmhg reads about .65 which is equal to 650 mmhg

 

thanks guys...i went out on the highway today and put the T2 in 3rd at about 60mph, floored it and the guage got a little above halfway on the orange curve. i do have a few mods...but the previous owner ported the wastegate...so that cut down the boost a fair amount i guess

 

your boost controller will always read higher because it's measuring the air out of the turbo. by the time it gets through the IC and intake to where your boost gauge is. the presure will drop by around 1 psi or so. which is why good IC's have very little drop.

and to add a note if you have an FCD your stock gauge is no longer right so don't even bother looking, as long as it moves.

 

wasn't talking about the stock guage, it doesn't move from pegged unless the ignition is off, first thing i noticed after install.