Only 5psi boost 89 shelby tona

[john1320]

-factory lines fell apart, as they always do on untouched TD's. Replaced with billet vac block as I always have in the past. I have the wastegate solenoid plugged in same manner it was removed . Right-hand post to source, and top post to wastegate. All i can think of this late is a blockage somewhere, which i can check in the morning. The solenoid bottom post (vent) pulls strong vaccuum, is this normal operation?
Very sluggish rise to 5psi, as if i were plugged straight to generic mani source.

[4 l-bodies]

On the GLHT (and other early turbo vehicles) metal solenoid pack, the top barb is vacuum/pressure source and the side barb is to wastegate. The way you have it listed in your post you reversed it.
Todd

[john1320]

On the GLHT (and other early turbo vehicles) metal solenoid pack, the top barb is vacuum/pressure source and the side barb is to wastegate. The way you have it listed in your post you reversed it.
Todd yes but they changed vents to bottom, on every 89 I have had

[turbovanman²]

Just hook up to manifold vacuum, if it runs aprox 5 psi and quickly, turbo is fine and boost controller/restrictor is bad, if still works like crap, turbo or can fault.

[GLHNSLHT2]

89 Turbo 2

http://www.thedodgegarage.com/turbo/turbo289.jpg

89 Turbo 1

http://www.thedodgegarage.com/turbo/turbo189.jpg

[Vigo]

I agree with simon.. If you're getting 5 psi but boost rise is sluggish, you probably have some non-vacuum-related problem on top of the boost control issue. Typically even on wastegate boost a stock turbo will spool pretty quickly. In fact, it seems many times when people have horrible turbo lag and can only make 5psi, their wastegate arm popped off.

[cordes]

yes but they changed vents to bottom, on every 89 I have had

See below. The TII is different from the TI boost control starting in 89.

The others are correct too in that there could be another issue. I would think it to be vac related since it's stuck at 5PSI which is about manifold vac boost on most stuff.

[john1320]

It's hooked up proper, wastegate arm is great, and boost is crazy fast (and can max 14.5 if i want too) when on my bypass. Do I HAVE to use the orifice? If so or not, what is it's purpose

[Vigo]

Well here's the thing.. If we're talking about boost rise purely as a function of the wastegate, the fastest boost rise would be with the wastegate closed. It'll stay closed if there's no pressure going to the diaphragm, at least up until 20 or 30 something psi.

It opens at 5-7 psi hooked straight to the mani because 5-7psi on the diaphragm opens the wastegate enough to bypass enough flow around the turbine that it will only spin the compressor enough to make 5-7psi. The only way to make it spool SLOWER at that point is to put pressure to the wastegate SOONER. But unless you're getting the pressure from somewhere besides the intake of the engine, there's no way to get pressure to it faster than having it hooked straight to the intake mani.

So what im saying is, if you get 5psi fast with it straight to the intake mani, and 5psi slowly with it hooked to the the solenoid, there is something else going on besides vacuum lines.

[john1320]

Will start going through troubleshooting when I do pops van tomorrow, before stuffing my face :)

[Tempted]

You didn't run the PCV straight to a vacuum source did you? Do you remember how much preload you put on the WG actuator? The easy way to tell if its your turbo is to take the vacuum line off the actuator and drive it around the block. If you get good boost then your turbo is fine and you need to look elsewhere for a leak.

[jackerman]

I had same problem. I found the swing arm siezed. Freed it up and then found the wastegate bad. Replaced it with adjustible on from fwd and now 20psi.

[john1320]

Well here's the thing.. If we're talking about boost rise purely as a function of the wastegate, the fastest boost rise would be with the wastegate closed. It'll stay closed if there's no pressure going to the diaphragm, at least up until 20 or 30 something psi.

It opens at 5-7 psi hooked straight to the mani because 5-7psi on the diaphragm opens the wastegate enough to bypass enough flow around the turbine that it will only spin the compressor enough to make 5-7psi. The only way to make it spool SLOWER at that point is to put pressure to the wastegate SOONER. But unless you're getting the pressure from somewhere besides the intake of the engine, there's no way to get pressure to it faster than having it hooked straight to the intake mani.

So what im saying is, if you get 5psi fast with it straight to the intake mani, and 5psi slowly with it hooked to the the solenoid, there is something else going on besides vacuum lines.

That's correct, there is something missing from this picture since all is fine, minus a possible bad solenoid or total failure on my part. I have a new camera, so will take a pic 1st chance

[turbovanman²]

So what happened bypassing the solenoid?

[john1320]

So what happened bypassing the solenoid? Refer to post #8? Going to put Evilcow's (TD member) eyes on it saturday and do some testing. I bet you anything the problem is likely staring me in the face... :mad:

[turbovanman²]

Refer to post #8? Going to put Evilcow's (TD member) eyes on it saturday and do some testing. I bet you anything the problem is likely staring me in the face... :mad:

So bypassing the controls and hooking up to manifold vacuum you hit 14+ psi? Then you have your answer, your can is no good or misadjusted.

[john1320]

Found a vac termination at the throttle body that had a check valve leaking some boost. Capped that spot went through everything & zip tied the usual spots. 1st time out car boosted great now back to square 1 again, sheesh :ballchain:
Will update thread if any changes