Max. PSI

[eclipser2001]

what is the maximum psi a 95 gsr can handle w/o messing with the engine internals. and what would i need to do to prepare my car for a turbo.

[Greenblurr93]

id say 6-8, safely, some say 10-11, but it all depends on the turbo your using.

[honda_racing101]

anyhwere from 6-8 id say safely and reliably

[V T E C H]

yeah, due to the high compression, i have heard like anywhere from 6-10 psi

[pepsihatman]

I would not want to run that daily though... 8 at the track might be ok, but the idea of high compression, a non-stock turbo'd car not engineered for boost.... I'd be wary about daily driving it. I honestly don't know how boost tough these lower ends are... also wondering about the valves, and interference, or valve float if too much boost.

[eclipser2001]

how would i prepare my engine if i wanted to go higher, lets say 11-higher

[knorwj]

I would say 5 psi daily, and around 8 and maybe 10 at the track but 10 may be pushing it.

in order to prepare it for more you would need to lower the compression. I guess to do a sloppy job you could just change the pistons and say the hell with it and run 10-12 at the track.

[eclipser2001]

Originally Posted by pepsihatman

I would not want to run that daily though... 8 at the track might be ok, but the idea of high compression, a non-stock turbo'd car not engineered for boost.... I'd be wary about daily driving it. I honestly don't know how boost tough these lower ends are... also wondering about the valves, and interference, or valve float if too much boost.

im a noob at this, does that mean i can't drive it everyday?

[travagliante]

No it means that driving and putting like 8 or 9 psi and driving it everyday puts a lot of stress on the engine.

Read up a little on turbos before you ask about how much psi you can run! There are many factors. I could run more psi on a smaller turbo and much just as much power on a larger turbo at a lesser psi.

With a good tune, id say a stock bottom end could hold 10-15 psi!( With a really GOOD tuner!)

[pepsihatman]

I didn't think the size of the turbo had any relationship to how much power per psi it puts out.... Usually size only matters in spool time and max psi possible. each psi should still add a fixed amt of hp, based on compression. The size of the turbo relates to the size of the impaler, and the size of the housing, which relates to the spool time, and possible boost. Please correct me if I'm wrong.

[superbluecivicsi]

search.

[eclipser2001]

can i upgrade my engine to be able to handle more psi daily.

[DeleriousZ]

Originally Posted by pepsihatman

I didn't think the size of the turbo had any relationship to how much power per psi it puts out.... Usually size only matters in spool time and max psi possible. each psi should still add a fixed amt of hp, based on compression. The size of the turbo relates to the size of the impaler, and the size of the housing, which relates to the spool time, and possible boost. Please correct me if I'm wrong.

you're correct when you say the turbo realtes to the spool time and possible boost(sort of) but, the size of the turbo has quite a bit to do with how much hp per psi it puts out. take a 15g stock turbo off of a talon tsi, and take a shiny new garrett t3/to4e and stick them on the same car, you'll find that you're making approx the same hp at 7 psi from the garrett turbo as you are at 10-12 psi from the talon turbo.

it's prettymuch got to do with how much air (cfm) the turbo can flow efficiently... where you'll get a slightly quicker spool up from the tsi turbo, the garrett is much more efficient, and will flow more air per psi. psi is prettymuch a useless number without knowing the volume of air the turbo is capable of (cfm)

now when it comes to max psi the turbo can produce efficiently, you'll find the numbers on most turbochargers are much higher than most engines can handle without some serious building.

[DeleriousZ]

Originally Posted by eclipser2001

can i upgrade my engine to be able to handle more psi daily.

yes but it usually requires messing with the internals... i wouldn't go over 15 psi without getting the block sleeved, rods/pistons usually top out around 10 on the gsr... compression is too high for boosting really, but if you get the right tune, you can make massive amounts of power running high comp and boost.

if you're really thinking about getting serious with it i highly recommend a good engine management system... the ones i can remember are hondata and the aem EMS... i'm sure there's new cheaper options out there, i just haven't been looking for a year or so...

[pepsihatman]

Ah, thank you deleriousZ. What you said makes perfect sense. cfm (cubic feet per minute) would really matter on the efficiency of the turbo. I imagine stock turbo's are not the best at being efficient, but aftermarket like Garrett would have put some research into it. My friend's Saab 9000 CD has a garrett t25 which seems to put out some nice numbers. He can run about 24 psi on the thing before it runs outta steam. It does outrun the fuel supply and somewhat drops off to about 18 at redline (5.5k). He mentioned something about an arc number that was supposed to be the ratio of the impaler to the housing, and said it affected spool time, and displacement of the boost. Thanks for clarifying that Z.