went to dyno today to tune my car. Stock motor with a turbo kit blah blah. OK here the problem. Cars loosing boost. First wee teed the dyno tuners computer into the back of the intake manifold were my boost gauge reads ok. Ran a run car hits 5 psi(wga spring) at 3200 and makes a steep fall to 0 psi by about 6000 rpms. Ok so then we move his boost input for dyno computer. We teed it into the compressor to wga line. Car held 5 psi from 3200 to redline. Which means somehow i am loosing boost somewhere between turbo and motor. I blocked off turbo inlet and the intercooler pipe off at tb filled to 15psi no leaks, I counted to 30 and it hadnt even dropped to 10psi. I had a leak at my throttle body coupling but not a super big one. Just big enought that when i filled with 15 psi it would whistle.

My question is where am i losing all my boost. Could it be a shitty intercooler. I bought it used so not sure brand. I just cant figure this out???

 

NOBODY HAS ANY CLUE????

 

what air filter?

 

no air filter the turbo inlets open for know gonna put a screen over it because theres no room to fit anything on inlet because of block clearance

 

Fix that boost leak. The smallest leak can rob you on alot of HP.

 

its not hp i am worried about its the fact i cant hold boost. I hold 5psi threw 3rd gear teed into turbo but at manifold boost falls off after 4000 rpms. So somewhere between turbo and intake manifold i am leaking huge amounts of boost. I found one tine leak in a coupler but tiny tiny. I really want to get this car tuned up but without finding this leak i am done. I am gonna which all piping and the intercooler tomorrow if i cant find another problem

 

Well, if you are getting 5 psi from teeing off the turbo and none at intake manifold than you are leaking somewhere. No air pressure into cylinder equal no power. Like I stated before fix that leak. That small leak can be the reason why the 5 psi from the turbo is not getting into the motor.

 

Other than a leak could there be another problem???

A bad intercooler, anything. Just trying to get all things sorted out before i try tuning again saturday

 

you have a BOOST LEAK....your leaking boost somwhere. I highly doubt theres any other reason why it would drop boost like that. if your intercooler was shitty that still means you have a boost leak. check all the couplers, and vaccum lines, bov flange etc... whats your setup btw?

 

OMG...how hard is this to understand.

<U> YOU HAVE A BOOST LEAK!! </U>

ok...now find it and fix it

 

I am running a custom setup. Its just a lil t28 sized turbo. Not looking for big # maybe 300 range for a fun daily driver.

Like i said I capped off turbo inlet and filled system with air from my compressor till gauge in car said 15psi. Held pressure for a long time. I found 1 leaking coupling but car still wont hold boost. I am gonna mess with it tomorrow and probably put a new set off piping and a new intercooler on there and see whats next. I just figure it would have to be one big leak to make boost fall off that much but i hope it was that 1 lil hole

 

Turbo is running out of juice...

what it makes the power and drops back??a t28 can only flow so much CFM

 

Boost leak and small turbo. With the CFM that turbo makes, and efficiency of that head, you won't be making much power at all. Change the turbo, fix the leaks. You may have more than one.

 

guys do you not read.

The tuner teed into manifold and i spiked 5psi and it fell
Then tuner teed into turbo and turbo held 5psi threw the rpm range.

Turbos bigger than a t28 but not as big as 57 trim. He said it should have no problem getting 300hp range.

 

Do you feel any power with the turbo on? Or does it feel like you're still riding on an N/A setup. If you can feel that the car is stronger than before then maybe you just have a shitty boost gauge or your boost gauge vacuum line is probably kink somewhere. But if it feel just like it was before you add the turbo on then you are leaking boost my friend.

 

It feels stronger down low but power dies as boost falls. We were going of the tuners dyno boost gauge and mine in car both fall. It must be a leak going out to work on it now

 

you need to know what turbo you have man.

Check your pipings, might be a loose clamp or a tore silicone coupler.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jfruauff &raquo;</TD></TR><TR><TD CLASS="quote">guys do you not read.

The tuner teed into manifold and i spiked 5psi and it fell
Then tuner teed into turbo and turbo held 5psi threw the rpm range.

Turbos bigger than a t28 but not as big as 57 trim. He said it should have no problem getting 300hp range.</TD></TR></TABLE>

An attitude like this without any further information honestly, gets you nowhere fast.

We are simply trying to help, and it is difficult enough to diagnose this on a web forum, when there is little information about what you've already checked to be able solve your problem, as well as no information as to the turbo used, it makes it even moreso.

We can simply say good luck to finding a resolution and no longer assist you if you prefer, but I'm sure that wouldn't be too nice.

If you could, please provide a bit more information about what you've done so far.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jfruauff &raquo;</TD></TR><TR><TD CLASS="quote"> Its just a lil t28 sized turbo.


Like i said I capped off turbo inlet and filled system with air from my compressor till gauge in car said 15psi held for a long time</TD></TR></TABLE>


i think the above is 2+2 = no boost, as in turbo falling off.. is what it sounds like to me.


unless there is some weird *** problem with the intercooler that i dont think that would be.


Modified by agrn93ls at 2:29 PM 11/1/2007


Modified by agrn93ls at 2:29 PM 11/1/2007

 

Ah yes, the HT-FI forum.. where some people have more money than brains.

 

guys turbo size has nothing to do with it. If we tee into the turbo it holds boost all threw 3rd. Somehow i am losing boost before the head.

I know the turbo is small i wanted a small turbo. Its just for a fun daily drive. Iall i am asking for is 300hp range which i was told by 2 local tuners the turbo is perfect size for it. Its a t3 flanged ( .48I/.67E a/r) I garrett said its a t28 style.

I just cant find any leaks but cant see why boost dont make it to motor. I have searched for leaks all day long. Cant find any. Filled car with air from my compressor and sprayed all piping with soup and water found 1 leak at a coupling and fixed that still wont hold boost.

 

I am not trying to be a dick. I am just getting frustrated. I am not a newbie to turbos either. I owned a srt that was all moded up and a gst eclipse. My first personal turbo honda but i have worked on a few others..

 

Have you checked the BOV? If your BOV is located between the intercooler and TB, is it possible that it may be leaking???

 

you need better coupler clamp maybe? or faulty coupler. or maybe simply your piping is to big for the air your turbo pushes.

 

We checked bov last time but ill check it again..

I ordered some t bolt clamps today to replace all the worm clamps. After that ill be lost.