First thing I'd like to say I have read numerous post that say ignore the factory boost gauge and get an aftermarket gauge. But seeing as I have priorities that put shocks, exaust and intake filter ahead of that boost gauge, I'd like to know what it should read , say at 6000and climbing in forth gear? I never see the needle hit the two hash marks on top. It gets to the beginning of the last *bar?* and then drops down to the middle of the next lower bar. I will get an aftermarket boost gauge eventually.

 

Hi HAILERS. Haven't talket to ya inna while. OK, here goes one of my long-winded diatribes....

:o 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.

Hey, it drops? Truth is, I have never seen it drop. By the same token, I don't have enough nerve to wind it over 6000 rpm in fourth gear either (I know, Ima Wimp!).

Irv, Keith's dad

 

Thanks for the reply, Keith's dad, Irv. I printed your reply and will keep it handy. It appears my car is not doing too bad. It presently is pure stock, which brings up the question as to what modifications are on your car. If it also is pure stock, then I question whether my car is normal. If you get a chance to reply, thank you.

 

Pure stock??? What did I spend all that money for???

Oh well, easy come, easy go. Our car has a stock turbo, engine, and emissions system. However, from the turbo back, it has a Bonez downpipe and hi-flo cat, and an HKS 60MM catback system. Oh yeah, it also has a bonez hi-flo intake. Man, I should be hitting fuel cut! Never have, though. Maybe it's because the mufflers on the HKS cat-back are not straight through???

Irv, Keith's dad

 

For what its worth...I started having low boost and not only that, it would drop down a psi after reaching whatever the peak was. It deteriorated until all I could ever get was 3psi. On an expensive hunch I ordered a downpipe and presilencer from Mazdatrix which I got yesterday. It now boosts around 7psi. Only driven it ten or fifteen minutes so far. So I guess the precat was clogged along with the cat. Maybe. Encouraged enought to want to buy the cat back from them, but I understand from reading a post today that there is a back log.

 

Hey Irv, Keith's dad, justed wanted to say thanx for the conversion factor. I've been looking for that.



Derek