boost drops at 6,000

[droptopgst]

Any idea what would cause the boost on my pte 50 trim to take 4900 rpm's to reach 23 psi. Then it holds there until 6,000 drop to 18psi and stays there until redline. I have checked for boost leaks, bov, is good and now I am clueless. Anyone have any ideas?

 

[oldman]

Are you seriously running 23psi on a 50 trim with stock injectors or is your profile not updated?

 

[ericbev]

Are you seriously running 23psi on a 50 trim with stock injectors or is your profile not updated?

He probably just forgot to add that to his modlist Ye' Oldman. Im hoping thats the case. From his cars pics, he seems to have a little idea of whats going on.

Did you just install your turbo? Give us some information to work with here.

 

[droptopgst]

Sorry guys, I just updated the mod list. I have had the turbo on for about 6 months or so. I also have denso 660's. The car is tuned for cruse, well kind of, the global is set to -12 but other than the wacked setting, its running great and my fuel trims are almost perfect. The wot is where I am having problems. The boost only holds at 22-23 psi for about 1k rpm's then drops to 18. I have little to no knock, with no boost leaks. No clue what would be causing this.

 

[oldman]

If the turbo is internally gated, try shortening up the flapper arm a little and see if it helps.

 

[BrokenTsi]

did you check it with a boost leak tester? Or did you just look around for leaks and couldn't find any? I'm going to take a shot in the dark........I think one or more of your intake manifold bolts are loose. Judging by personal experience, my car did exactly what yours is doing when a few of mine rattled themselves loose.

 

[droptopgst]

Well I did the psi test with up to 26 psi, soap, and water. The main leaks were from the bov screw and the afpr screw. They were both fixed by thread locker. What do you guys think of this?

Was this a valid test? I disconnected the boost controler and hooked the line from the turbo into the w/g actuator. At wot I get the highest of 9 psi around 3,800 rpm's and it holds there till redline. I was thinking that this means I have a 10 lb actuator? I have no clue why a company would put such a weak azz actuator on a turbo that is said to run best at 22-30psi.

Anyone know of any tricks I can do to fix this or do I need to buy a whole new actuator?

Thanks again for everyones input.

 

[DiamondStarM]

You can try shiming the actuator. There are mixed feelings about it, but if your actuator arm isnt adjustable it a cheap alternative. I currently have one washer on all my actuator bolts on my B16G, nothing to serious but it holds the flapper a little tighter.

 

[DSM90AWD]

Try this. Disconnect the wastegate arm from the flapper lever. Do you have to pull the arm outward to reconnect or is it even?

If even or you have to push the arm into the actuator to get it back on you're flapper doe snot have the correct pre-tension and is likely not fully shut while building boost hense your suck-azz spool times.

Remedy woudl be to "adjust" the arm to give slight pretension, or if not adjustable, add washer(s) to the WG mounting bracket

 

[droptopgst]

I shortened the w/g arm, so it had to be pulled aout 1/4" out to hook it up. I get 20 psi by 4200 rpm, and holds till redline. Much better, thanks for the help.

 

[DSM90AWD]

I shortened the w/g arm, so it had to be pulled aout 1/4" out to hook it up. I get 20 psi by 4200 rpm, and holds till redline. Much better, thanks for the help.

Kewl

 

[daren_p]

Good to hear you got your problem sorted out, WG shimming worked great on my non adjustable evoIII actuator. Was just wondering doesn't 4200 rpms still seems abit slow spool on a 50 trim @ 20 psi? Have you checked to make sure you don't have any exhaust leaks as well?

 

[DSM90AWD]

Was just wondering doesn't 4200 rpms still seems abit slow spool on a 50 trim @ 20 psi?

4200 seems about right for an internally gated 50-trim (what mine does anyway). 25psi comes up a few 100 RPM more