gt4 boost query (st-185)

[downsouthdave]

hi i have just brought a gen 5 gt-4 cheap i was wondering if any1 could help me. if i turn the ignition on boost gauge gose to just under 0 (were it should be so iv been told) start the engine and it gose to -???? so i gave the car some throtle to about 3.500rpm and i dont seem to be getting any boost. i have taken the pipe off to were the air filter conects to the turbo and the turbo impeller dose turn i have also checked the pipes that i can get to for air splits but no joy. so anybody help me out???? thanks alot dave
sorry i forgot to say i dont seem to be getting any turbo noise when i rev it up like a forced induction noise

[Yaggus]

ok so im assuming you mean uve just had it in neutral when youve been revving it.

The stock boost guage is USELESS!!! get an aftermarket one put in. the stock one has about a 2 second delay in it.

As for your other questions. yes when you start it it is supposed to go to 0 and then drop back down at idle because you dont have any compression running through your engine. take it for a spin and you will find the turbo starts spooling up at ~2800 rpms. again assuming its the stock turbo.

its really hard to get a response from the stock boost guage when at idle. by another one.

[nialusa]

Dont worry mate, that happens on my`n too, Like Yaggus said, get an after market boost guage (it dosnt have to be an expensive one) and you will realise how shite and slow the standard boost guage is.

[LaYzIeNoY]

same thing here don't worry about the stock one it doesn't do crap

i always see it trying to catch up to my Autometer boost gauge lol, also if you're running cimpletely stock then you should be on a VSV, soo boost pressure will change from time to time, good conditions defined by the ECU

[jaybratt]

What if you were to tweak the ecu to where it always thought it was good time for boosting. In other words bypassing the VSV completely, would that be risking blowing anything???

[LaYzIeNoY]

not sure, maybe

you bypass the VSV if you install a electronic boost controller

but on a completely stock systemt he ecu can use it [vsv] as a safety if you running hot or some problem arises

[jaybratt]

I never thought about that. The manual boost controller would have to bypass it, otherwise the vsv would cause it to not even work. AHHHH. I feel so wise now, like a mini buddha or something.

[nialusa]

Dont disable the VSV unless you have a boost controller, either a manual one or an electronic one, (by the way, your car will only boost under load, in neutral you will not get any boost). Dont raise the boost pressure to much or you will blow the head gasket. electronic ones are best as they will offer some sort of protection. With an electronic boost controller, expect the turbo to spin up 1000+ RPM sooner much faster acceleration, even on the same boost setting as standard (I would tell you why but I cant be bothered to get too technical), and a big smile on your face as you fly by cars that previously would beat you.