Boost Creep Problems

[1986.5supra_kid]

2jzge na-t with ebay twin scroll and 50mm drift motion WG and a 56mm Holset hx35. Psi is set at 16 but on a long wot pull it climbs to 19. I had a manifold gasket fail die to a bolt being loose so I'm going threw all of the co next ions to check for leaks. I have been told that my choice in manifold and WG are the problem. that's a hard pill to swallow. So what can I do to check for my culprit?

 

[IndigoMKII]

normally creep is due to not enough flow, is the wastegate installed correctly with nothing in the way?

 

[525gte]

I run an eBay header and a precision 46mm wg and have no issues. I and a precision 6262. How does your exhaust look is it free flowing

 

[IndigoMKII]

I think he's using a .8x size turbine housing.

 

[1986.5supra_kid]

the WG
http://store.driftmotion.com/static/i-wg50mmhks.php
and a aem boost controller ran by the aem v2 ems. the boost guage is how i know it creeps and the tuner told me too

as requested here is the manifold





tight fit

bottom side looking up, close to frame.

1'' riser and .5''adapter close fit. rubs sometimes

 

[525gte]

Are you running an aem tru boost? Is the spring cracking pressure set up correctly? If it's not you will get boost spikes and than it may not be able to recover fast enough

 

[nathaninwa]

I have that same header with the same wastegate that 525gte has. I have a bit larger 6466 Precision turbo with .84TS T4 housing, when I had my small spring inplace, I could maintain 8psi to readline with zero creep.

Id look around at other things and maybe header backpressure at the given boost level.

And that the gate is free to move fully open.

Do you have a dump pipe that bolts to that?

 

[MDCmotorsports]

You have the Holset gate welded shut?

If so, it sounds like the external wastegate is loosing signal (boost) or the valve doesn't move freely (sticking partially shut)

 

[1986.5supra_kid]

this might be part of the problem. this is the pipe that connects to OUT on external WG


here is the rest of the pipe. this was done because WG is crazy loud


I was afraid of welding the internal WG because i didnt know if i would like the turbo so i done this to close it and if the ebay ever got stuck closed, my failsafe will trigger and ill get the hint and unbolt this.



EDIT: i have had the turbo on and off multiple times due to the turbo drain line leaking. ebay fittings=poo poo. russell fittings on the way. so maybe from taking boost line off compressor housing has caused it to leak. can i use air compressor to check my lines for WG and WG control for leaks like i Do with soap and water. or will i damage something? i doubt it but still i ask.

 

[nathaninwa]

you can do that, just turn the regulator down to 20psi or so and you wont have any trouble. check to make sure the gate is opening fully and the valve stem isnt bent.

What size is your main exhaust?

I know you said you had it tuned, but how does your timing map look? high egt's from retarded timing can cause this too.

 

[1986.5supra_kid]

you can do that, just turn the regulator down to 20psi or so and you wont have any trouble. check to make sure the gate is opening fully and the valve stem isnt bent.

What size is your main exhaust?

I know you said you had it tuned, but how does your timing map look? high egt's from retarded timing can cause this too.

Here is a link to a thread that I had posted my calibration file on it is post #5 "battlegroundnotsure.cal" is the current one on car
http://www.supramania.com/forums/showthread.php?184332-Is-this-the-beginning-of-a-BHG

My main exhaust is 3" from turbo to tail.

 

[1986.5supra_kid]

Bump

Bought a 44mm MVR tial.

 

[hvyman]

I would the right size screamer pipe as well. I just went to a fab shop for mine.

 

[-AR-]

How do you like the hx35? What's spool like?

 

[1986.5supra_kid]

8psi by 2500rpm 16@3200 loves to spool. Just in town you'll hear it whistle.