Chas

So I bypassed my cycling valve...so that's straight tubing running from the intercooler pipe to the waste gate...and I'm seeing

16psi in 2nd
17psi in 3rd
17.5psi in 4th

What the heck??? Is my stock wastegate getting stuck closed???

Is there any way of pressure checking this from the pipe right off the intercooler, like should I be able to put 10 psi on the line and "hear" or "sense" something open or click in the wastegate?

GWTurboS

Do you have a completely stock wastegate? Reading your sig it says you are also using a LBE. Do you have the LBE running in between the incooler pipe and wastegate? Also, where are you getting your boost signal from for your gauge?

On my 88 TurboS I am running the APE stage II chips, stock turbo, and I run from the intercooler pipe, through the LBE and then directly to the top of the stock wastegate. With the LBE set almost at full boost (2-3 threads showing between the jam nut and the male fitting, I am pulling about 15 psi in the midrange. My stock wastegate is not shimmed yet, so on the high end the exhaust pressure pushes the wastegate open regardless of what the LBE is set at and my boost drops down to around 11psi.

I am pulling my boost signal from the vacuum line leading to the KLR computer.

Best Regards
Greg W.

Chas

Stock wastegate...I took the LBE out....it's just a straight line

I am reading the boost from the manifold using an aftermarket gauge...

Any other help???

Chas

anyone?

mochman

dunno on my 86 with a boost enhancer t04e and stock w/g sometimes I see 15, 17 and oh yeah last night racing a turbo eclipse I saw 20 for a sec then it backed down to 17. It's getting a tial and an mbc real soon before I scatter parts.

facboy

my understanding is that it's normal to see higher boost in higher gears, ie you'll see higher boost in 4th and 5th than in 1st, 2nd or 3rd.

Danno

You may also have a broken vacuum hose going to the CV, or the section down to the wastegate. This will vent out air that should be going to the wastegate to open it. The result is more boost than planned.

Chas

Since I bypassed the CV, I know there is no leak until the wastegate hose. Also I cannot blow any air through the line...so I assume the line has no major leaks...

...with this straight-line setup...I should see no more than about 7 psi...we're talking original wastegate and original spring after 150k miles

special tool

Take off the pressure line at the banjo and put 15 psi into it with the motor shut off. You should hear the valve shut after you stop the air.

jimbo1111

Are you still using the banjo bolt supplied with your ape chips? If so remove it. If memory serves there is a restrictor in the banjo bolt.

Chas

It is straight hose from the IC pipe to the last hose that goes to the WG