Where's the boost?

[KCODE]

1986 Buick Grand National (45,680) T66 Turbo #42 injectors with TT Chip, Adjustable Wastegate, Manual Boost Controller, BOV, VDO Boost Gauge, Walboro fuel pump, hotwire kit, cc delete, scan master, spring cleaning, stock everything else.

Issue: My turbo will not boost past 12lbs.
What I've done: fixed exhuast leaks, tuner run set up (by passed the boost soleniod), adjusted wastegate, adjusted manual boost. Checked for leaks. Ordered new boost soleniod and y hose going back to stock set up and see if that helps.
Help?????

 

[Amelio]

does the waste gate arm move freely? I fought that on mine .....rust build up where the arm goes through the down pipe....once it opens it will not fully close and causes to much bleed off......

 

[Bescurred]

Do you have an HD actuator? I could only get 20 psi on a TE-60, upgraded to a HD and easily was going up to 25psi. What downpipe do you have on the car?

 

[87geeinn]

Since you have the wastegate set up tuner style, then you will only see 12psi max...assuming you do NOT have a heavy duty wastegate and have not added additional tension/preload to the wastegate arm. So, what you are describing is perfectly normal.

Once you add the Y-hose and wastegate solenoid (and install it properly), you will see more boost. The purpose of the y-hose is to route boost pressure to the solenoid, which in turn bleeds of a measured amount of pressure allowing you to run higher boost.

 

[KCODE]

Do you have an HD actuator? I could only get 20 psi on a TE-60, upgraded to a HD and easily was going up to 25psi. What downpipe do you have on the car?

Not sure it was already in the car when I purchased it. It is adjustable though. I believe it is the stock down pipe.

 

[KCODE]

does the waste gate arm move freely? I fought that on mine .....rust build up where the arm goes through the down pipe....once it opens it will not fully close and causes to much bleed off......

How did you fix it?

 

[KCODE]

Sounds good but I thought in tuner style I would see 17lbs of boost.

 

[earlbrown]

Tuner style you can see what ever boost you want depending on how tight you make the wastegate. Is this a new problem or something that's always been there? The reason I ask is I wonder if the wastegate puck is fully covering the hole on the turbo.

I had a header crack one time that wouldn't let me get more than 15 with the wastegate tied shut.

 

[KCODE]

It recently started after I fixed the exhaust leak (passenger side header). Prior to that I was able to get 16lbs with the same set up.

 

[87geeinn]

Sounds good but I thought in tuner style I would see 17lbs of boost.

Tuner set up with no preload with a normal wastegate actuator equals ~12psi; heavy duty wastegate equals ~17psi

I say take pictures of your setup and start listing some specifics (i.e., turbo plumbing, header to turbo connection, passenger side header, what kind of manual boost controller, downpipe, etc.). There are so many unanswered variables to this equation that it is about impossible to determine the root of your problem. I can almost guarantee that going to a stock setup in an attempt to get a handle on your issue is not going to solve the problem.

 

[SHADOWII]

Have you checked the center section of the turbo to insure it turns freely and is not coked up?

 

[Amelio]

How did you fix it?

If you had the car making 16psi prior to your header fix then I kinda doubt you have a puck alignment issue....also if it was working well prior then the waste gate rod is probably ok too........when you un hook your actuator rod from the puck assembly it should be really nice and loose. Mine would get carbon and rust in there and freeze up. The fix I did was taking the down pipe off and cutting off the puck assembly to remove the entire unit. I then drilled open the hole so the assembly moves freely then welded it back together. I have not had a problem since and the assembly is loosy is goosy even when its hot!

I also run tuner style and with the rod threaded in 3 turns I get 17 psi.....I actually just put the "y" pipe back on two weeks ago before I went to the track.....it also helps spool time due to the orifice in it which restricts the air flow back to the accumulator reducing the pressure keeping the gate closed longer......it helped car spooled faster and picked up my 60'. The other end of the "y" is capped off I will be installing a bleeder valve to increase my boost since the car does not make much over 17psi the way it sits.....I can turn it in a few more time still 17psi.

Where is the rod setting now? Is it in the "half moon" setting? if so double check that the puck assembly moves very freely if so turn your rod in ( basically make the actuator rod shorter") go in 1 turn increments boost should increase you can do this in "tuner" style omitting the stock solenoid so it does not bleed off. Or if your brave enough wire the gate shut it should spool fast and boost should go up to where ever it is going to make with your setup. Just lift real quick when you hit the desired boost or else bad things happen lol......

 

[earlbrown]

It recently started after I fixed the exhaust leak (passenger side header). Prior to that I was able to get 16lbs with the same set up.

In that case I would start with the two x-over pipe connections, the PS manifold to turbo connection, manifold to head, then verify the DS header hasn't cracked again and showed itself while you were messing with the exhaust.

checking the puck swingarm will only take a second and it's unlikely that it gums up at the exact instant you repair a leak....


......but goofy coincidences like that are not unheard of with these cars.

 

[KCODE]

Got some pictures of the current setup. This is how it was when I purchased it. Hopefully this helps you help me.

 

[earlbrown]

I see three things you need to do right now to troubleshoot. first get some new hose and replace all three pieces between the turbo, wastegate, and boost control solenoid (that won't raise your boost. it's preventative maintenance to keep from overboosting and blowing the engine).

On your boost control solenoid, take the short piece of hose with the screw in it and toss it. That port is supposed to be open to the air so the computer can raise the boost level when it wants to. Blocking it off slows spool and keeps the maximum boost at the wastegate setting.

Tuner style if fine for now until you sort out your boost issue.

and third, toss that ricer blowoff valve, or at least block it off so it can't vent pressure. I'm almost wondering if that is your entire problem. you might have a big ass dump on the side of the up pipe venting boost.

 

[dr_frankenstein]

how long has that Ebay turbo been on the car?

 

[forzfed]

and third, toss that ricer blowoff valve, or at least block it off so it can't vent pressure. I'm almost wondering if that is your entire problem. you might have a big ass dump on the side of the up pipe venting boost.

Oh, no you didn't.

 

[KCODE]

how long has that Ebay turbo been on the car?

I dont know was on the car,when I purchasex it. Ive had the 8 months.

 

[KCODE]

Oh yes be did. I knew where it came from but when I took it off and checkex it seemed fine.

Oh, no you didn't.

 

[earlbrown]

How did you check it? A visual something involving blockoff plates and compressed air?