how much boost?

[ednutcracker]

how much boost should a garret t3 .42 .48 be doing in a 2.5 and the wastegate conected to turbo vaccum nipple, the wastegate is adjustable and it seems to be making alot more than 5 psi

[mwinkle353]

if it's adjustable, then you can run over 20 psi with it. I'm assuming that you don't have a boost gauge. I'm also assuming that you're not running past fuel cutoff (14.5psi).

I'd highly recommend getting one before you start damaging things.

[ednutcracker]

i had the gauges , but not insta;;ed yet, today i installed the boost gauge and its at 9 [psi in all gears, fells peppy but i got this problem that i cant rev past 4,500 rpm fells like overboost cutout but its at 9psi and no spikes.. i changed the hep and nothing im guesing either the map or idle speed sensor

[mwinkle353]

does it feel like a rev limiter or more like overboost?

Soft or hard bucking?

[daytonajesse]

Where is the boost gauge hooked up to? Sometimes you can get false readings from certain locations. What does it read for vac at idle?
Check your codes it should tell you the whole story.

[ednutcracker]

its pretty hard...like trying to stop the car..., the boost gauge is conected to the throttle nipple, codes are 13 54, changed the hep no fix.....bypassed the barosolenid...nochange

whats strange is that at idle it dosnt read vacum it reads 0 and sometime when i acelerate it goes to 10 15 vac then 9 psi boost

[daytonajesse]

You cant use the tb for a vac/boost source for your boost gauge. I bet if you tee it in to the intake manifold, you'll see a vac signal and notice your hitting overboost 14.5psi or so.

[ednutcracker]

ill check using a T on the map/fpr source but why the throttle is no good place for the boost gauge

[tkelly27]

thats a ported line, its in front of or right in line with the throttle body, IIRC the readings you get from that will be wrong because it's flow based, not necissarily boost based. If you used the other nipple on the TB it might work ok, but the boost @ the TB is not what you want to know, you want to know what the manifold is seeing. If you are for sure not getting boost cut out see if you get cut out engine braking downhill past 4.5k.

[ednutcracker]

i changed the boost gauge to the map source and it read now 20 vac and 9 psi the boost lecture is the same but it did change alot the vacum response on the gauge, im still getting the "cut out" any toughts?