[GLHS #26]

Hey I was wondering if anyone had some idea to help me. I have a turbo mini with at3/t4 turbonetics turbo on it and when I drive it it will do 2 to 3 hard pulls when the turbo spools fast and then after that it will spool very very slowly and maybe make a max boost of 7-9 psi. If I shut it off and let it sit for 10-15 mins it will spool a coulple times again and then stop.

Does anyone know what could be wrong or what I could do to get it to spool all the time?

 

[tryingbe]

Are you using a G-valve?

 

[Sittn86]

have you checked for fault codes?

 

[Screamin4banger]

Does it have water lines?...or just oil? Hows the oil pressure? What kind of oil? Dino or Synthetic?

A thought comes to mind, but I hope its not this... But it sounds like heat.

Like the turbo works real hard, the metal expands, clearances get too tight, turbo struggles to spin, you shut it down (maybe coking the the oil?), the metal shrinks, clearances come back...

Rinse and repeat.

Is this a new problem? Was this turbo fine for a long time and now just started doing this?

 

[GLHS #26]

Thanks guys, To answer some questions yes I have g-valve. The turbo I beleive is water cooled. I just bought this van from Dempsey Bowling about 2 months ago. He was running 13.5s in it with a custom cal and a big IC that he kept but the turbo is the same one he used.
I am also afraid that the heat swells the turbo causing the clearances to be to small.
Any sugesstions on reducing heat. If it is bad in the winter I bet summer is going to be worse.

I am using just regular 10w30 oil I dont know what dempsey was using but as far as I can remember it did the same thing before the oil change. But I guess it is worth considering synthetic.

 

[bhazard]

ALWAYS use synthetic on a turbo!

 

[turbokid]

And he kept the front mount intercooler??? Did you put another intercooler in there??? and yes especially with higher boost and a big turbo always synthetic. Are you running higher octane aswell???

 

[Screamin4banger]

OK.

Heres some more to think about...
You said he kept his big IC, do you have any IC? If there is no IC at all, I imagine you wouldn't have the related piping and BOV either. Forget for a minute the engine abuse of running a big turbo, custom cal and no IC, and think about whats going on with those boost pressures when the throttle blades close. Please tell us you have a BOV.
Big boost + lack of BOV = beaten and abused turbo.

Synthetic oil is resistant to coking. Coked up oil lines and CHRA prevent oil from getting where oil needs to go. Running Dino oil means you need to be really disciplined in not shutting down hot. Thats what turbo timers help with - keeps the engine running for a while so the turbo can return to a "safe" temperature for shutdown. Find out if you have coolant running to your CHRA. If you do not, the oil is acting as BOTH lubricant and cooling system. Coolant lines also help after shutdown by drawing heat away by convection.

good luck

 

[turbokid]

+1 To that

 

[MVaughn]

Check the operation of the wastegate arm making sure it isn't binding and moves freely. Lack of synthetic oil isn't your problem. Look elsewhere. If you have a b.o.v. bypass it so you know thats not the problem.

 

[GLHS #26]

I do have a IC a stock mopar one. I am almost positive that it is not a boost leak issue because I have blown up a couple of hoses before and with that big turbo you it sounded like someone turned on a leaf blower under the hood.
I do have a BOV and it is just the stock crappy one but I have taken it off many times and plugged it and it will do the same thing. It is like the turbo just stops spooling.

My next idea is what MVaughn said about checking out the waste gate and possibly shorten the actuator arm.

thanks for your suggestions

 

[MVaughn]

Sorry for the delay, I just got home from a work function. I would check to make sure the wastegate moves freely w/ you pulling on it some (when it's cold). This will give you a idea if it could be the problem. It is possible that when you run the car a few hard times that it is heating the exhaust housing up some just enough to cause it to bind. Look to see that the actuator arm isn't close to any objects that could prevent it from moving freely. Have you taken the factory solenoid valve for the wastegate control out of the loop. You should if you are using the grainger valve. If you haven't do so and see what happens.
I will be up for several more hours to see what you come up with.

 

[Gutfeeling]

Heat Soaking issue. Install a meth/alky kit or water cooled IC.

 

[MVaughn]

While everyone has there opinion I don't feel this is it. If heat soak was the issue why would you want to install a water cooled IC? He mentioned he has a intercooler and a air to air is by far a better system overall on the street.

 

[Gutfeeling]

If you run a separate water system for the IC with a fan attached to it, it will run cooler than the air/air style IC.

 

[MVaughn]

For a daily driven car this is Not the best choice. If it is heat soak he needs to find out why the car is heating up beyond the point of keeping the temps down. Possible items could be broken knock sensor, wrong ign./cam timing, clogged converter, radiator,cap, ect.
The list could go on if that is the problem. How are the temps. after running it a few times?
Buying another intercooler, running the plumbing, another fan,pump, adding extra weight, relays, wiring, ect.?? all to find out that isn't the problem.
Very few factory cars run this system. One comes to mine is the gmc syclone and i do know it has problems w/ heat soak when running it hard. Again, I have to disagree w/ your statement but thats ok to disagree w/ one another.

 

[MVaughn]

Please post more info. on the car. I might of missed part of it but are you running a intercooler, what injectors, is the computer controlling the boost along w/ the g-valve. Does the temps go up when running the car hard? If so does the temps come back down quickly? If you are not sure I would ask Demsey I am sure he will be more than happy to help you.

 

[GLHS #26]

Thanks for all the opinions. First as I mentioned to Mvaughn in a PM I am thinking a posibility of a sticking wastegate.
The overall van specs are:
2.5 balance shafts removed
52pph super 60 injectors
stock 88 computer
AFPR
ported exhaust man
Turbonetics t3/t4 with oil and coolant lines.
Auto tranny w/ reverse manual valve body
A/C components all removed
A stock MOPAR IC next to the radiator where the A/C condensor was.
Everything else stock to my knowledge.

Any tips on trying to fix/ check wastegate is sticking? Or will whortining the rod help it? A Lubracant or cleaner to free it up?

 

[MVaughn]

Are you running a grainer valve? If so are you running it w/ the stock boost solonoids as well?

 

[zach]

ALWAYS use synthetic on a turbo!

it doesnt really matter wat oil you use on a turbo as long as its good motor oil other wise if you put in a new motor but you were using the same turbo as you had before how the hell would you break in the motor on synthetic???