Why is my 20g maxing at 15psi???

SpooledSleeper

SpooledSleeper

New member
Ok, as the title states my 20g is maxing out at 15lbs of boost. I'm trying to achieve 20-22lbs. I have done all I can think of as far as tuning the chip and preloading the wastegate. I've tried to search with no luck 0_0 I know the 20g is capable of more than 15, basically Im just wondering if anyone has any ideas, because as we all know, two heads are better than one.
 
RydinLowSince2000

RydinLowSince2000

13.84 @ 98 mph
Re: Why is my 20g maxing at 15psi???

SpooledSleeper said:
Ok, as the title states my 20g is maxing out at 15lbs of boost. I'm trying to achieve 20-22lbs. I have done all I can think of as far as tuning the chip and preloading the wastegate. I've tried to search with no luck 0_0 I know the 20g is capable of more than 15, basically Im just wondering if anyone has any ideas, because as we all know, two heads are better than one.
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Maybe adjust the waste gate. I'm assuming you have a 3 bar map. The only other thing I can think of is your timings retarded. What do I know though my trucks pretty much bone stock as far as engine n turbo goes.
 
TYTILIDIE

TYTILIDIE

METH HEAD
Re: Why is my 20g maxing at 15psi???

Have you really tried EVERYTHING? Did you wire the wastegate shut to be sure like I said. It's like I told you, if you try that and it still wont go any higher then something is wrong with the turbo.

For everyone else reading, here is the rundown of the truck, no cat (well hollowed actually), running alky, 22* of timing. This is my wife's old Ty # 0965. Truck runs great otherwise, 0* of KR under boost. Brent, you have to wire that shut before you can make any further diagnosis, otherwise, no one will really be able to answer your questions intelligently because you are telling them you tried everything so they assume you tried wiring it shut. It could very well be that turbo is worn out and just can't do any more.

I had the same thing happen to me on my 20g years ago that was on my black Ty back in the day. FWIW, my friend Chris has his old 20g laying around he is willing to let us borrow to see if it fixes the problem.
 
BMFB

BMFB

Not to scale
Re: Why is my 20g maxing at 15psi???

I would recommend a boost leak check and a 'play check' on the turbo before I would tell you to wire the gate. its probbaly a goofy vaccum line, which a leak check would find for you.
 
TYTILIDIE

TYTILIDIE

METH HEAD
Re: Why is my 20g maxing at 15psi???

BMFB said:
I would recommend a boost leak check and a 'play check' on the turbo before I would tell you to wire the gate. its probbaly a goofy vaccum line, which a leak check would find for you.
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Doubtful, all vacuum lines are instant fittings. If there was a leak it would have to be in the BOV itself which is always a possibility.
 
BMFB

BMFB

Not to scale
Re: Why is my 20g maxing at 15psi???

my vacuum lines dont usually leak at the fittings...although I dont trust 'instant fittings' either. boost leak check is really all I was pointing to, its the best way to find issues like this and its always the last method used...

case in point, "wire the gate shut". lets think, why would you do that...ok, to see if the turbo is capable to producing any more boost. what could it show to be at fault? waistegate actuator? boost controler? vacuum line going to those parts? no, not really, it just shows that yea, you have a problem somewhere. the only case it would show you anything is if you did it and boom, no more boost...wait, but that could be a leak somewhere in the intake...or hot pipe...or brake booster, or intake plenum...the only thing it really cant show you is if the fins got torn from the turbo. most gates will leak if their seals are blown, so it works for those too.

the risks of something like wiring the gate shut might seem minimal, and sure, one split second of completely uncontroled boost never hurt any motor, right? I'll tell you the worst I ever heard a motor detonate was someone doing just that (it was me btw, forgot to take boost off 22psi in digs 'starter bin')
 
TYTILIDIE

TYTILIDIE

METH HEAD
Re: Why is my 20g maxing at 15psi???

BMFB said:
my vacuum lines dont usually leak at the fittings...although I dont trust 'instant fittings' either. boost leak check is really all I was pointing to, its the best way to find issues like this and its always the last method used...

case in point, "wire the gate shut". lets think, why would you do that...ok, to see if the turbo is capable to producing any more boost. what could it show to be at fault? waistegate actuator? boost controler? vacuum line going to those parts? no, not really, it just shows that yea, you have a problem somewhere. the only case it would show you anything is if you did it and boom, no more boost...wait, but that could be a leak somewhere in the intake...or hot pipe...or brake booster, or intake plenum...the only thing it really cant show you is if the fins got torn from the turbo. most gates will leak if their seals are blown, so it works for those too.

the risks of something like wiring the gate shut might seem minimal, and sure, one split second of completely uncontroled boost never hurt any motor, right? I'll tell you the worst I ever heard a motor detonate was someone doing just that (it was me btw, forgot to take boost off 22psi in digs 'starter bin')
Click to expand...

I know you think I am new here but I have been around the block a few times. I was working closely with Brent on this but he doesn't come around much so it is hard to figure out the problem not having the truck here. Do you really think I would tell him to do this if we didn't investigate other things first? Give me some credit, I've put more miles on my Ty than most owners will ever see, do you think I don't know what I am doing?

If the guy would bring the truck by I could certainly help him fix this or figure out the problem but I have to think simplicity here, he has no real tools from what I have gathered and a lot of tests have already been done. Hell, I did a leak test the day he bought it and it didn't leak anywhere. Of course that could change but my point is, steps have been taken to figure this out, Brent just doesn't have a lot of time or know how to figure it out or bring the truck by I guess.
 
V8 Sonoma GT

V8 Sonoma GT

Mile High SyTy
Re: Why is my 20g maxing at 15psi???

Brent showed up! Before you figure this problem out, i want a rematch with that truck hahaha
 
TYTILIDIE

TYTILIDIE

METH HEAD
Re: Why is my 20g maxing at 15psi???

V8 Sonoma GT said:
Brent showed up! Before you figure this problem out, i want a rematch with that truck hahaha
Click to expand...

You'll lose dude. I spent an hour or so tuning it and at 15psi it pulls hard, quite a bit harder than yours. Once he gets this worked out it will be on. You're doomed until you get a new converter IMO. That thing isn't cutting it. Yours will get there though, it's just going to take some work. I say lets arrange it though.
 
TYTILIDIE

TYTILIDIE

METH HEAD
V8 Sonoma GT

V8 Sonoma GT

Mile High SyTy
Re: Why is my 20g maxing at 15psi???

yea, since i figured out the boost controller, we prob need to do some more work on it, on current tune, it runs the same with/without meth
 
0966Sy

0966Sy

Code what?
The 20g wastegate will not work with the stock boost solenoid. The wastegate may respond well to a boost controller of some type. In my opinion that wastegate is a POS. The base spring pressure on it should be around 8-10psi, reason for you only getting 15. Also you do not adjust boost pressure with the wastegate rod. You use it to set the correct preload recommended for that wastegate + or - one turn for fine adjustment. If you want to run 20-22psi solid without a controller than you need a forge wastegate with the red spring or one below it if your at higher altitude.
 
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