I have a 99 STI v5 and wanted to check what boost it should be running. Currently on full throttle it runs between 0.8/0.9bar. Car is standard apart from decat downpipe and using optimax.

Thanks!

 

Damned if I know, I've asked many times in the past for what a MY05 STI PPP Type UK should have and nobody seems to now for sure. I get about 20psi peak dropping to about 17psi at high revs. I think 1 bar + 14.75psi or ther abouts. Good luck anyway.

 

Just called Subaru UK and they Quoted this for the MY05 STI PPP:-
18 psi max peak for STI
19 psi max peak for STI PPP (stated it was more of a mapping change than boost that gives the power increase)

May be worth a call to ask about yours. Looks like mine is about right then.

 

99-00 uk turbo are supposed to make just over 0.9 of a bar of boost, so that seems a little low for an STI IMO, think it should be more like 1.1-1.2 bar.

 

I would've thought an STi would be similar to my remapped WRX - 1.25bar.

 

From memory 1 bar = 14.75psi
so 1.2 x 14.75 = 17.7psi

so 1.25 x 14.75 = 18.43psi (see post below)

so 1.36 x 14.75 = 20.06psi so I am getting peak of about 1.36bar, holding a reasonably steady 19psi (1.28bar) dropping back to 17psi (1.15bar) at max revs. Unless I am supposed to have this PSI/BAR at max revs (Subaru said not, just at the peak) it would seem I am about spot on.

Please feel free to adjust figures if my "1bar = 14.75psi" is wrong (which I could be). I have alos heard that Boost Gagues tend to under read slightly, so that is good news, as it would mean I am slightly over the actual figures stated for my model, whey hey !

 

My peak is 1.33bar, normally max's at 1.30bar though and holds 1.25bar.

Try this conversion site for accurate pressure conversion figures

http://www.onlineconversion.com/pressure.htm

 

done a google search and there are various quotes of pressure conversion of 1bar + anything form 14.5 - 15 PSI
although 1 bar is actually less than 1 atmosphere, get a bit confusing here.

just found this link for a conversion table: http://www.engnetglobal.com/tips/convert.asp?catid=17

If you put 1 in the "bar" box it returns a forced pounds pressure of 14.5psi. That is good news for me as 20psi then = 1.38 (max peak) and 19psi = 1.31 (steady boost) and 17psi = 1.17psi (min boost at max revs)

 

Spot on mate.....matches what I got, good news, no need to worry about my boost pressure anymore as, if anything it is slightly up on normal for a MY05 STI PPP.

 

What car/ MY etc have you got and I take it, it is moded too?