Go Back   AstinaGT Forums > Performance & Technical > Performance & General Maintenance

Reply
 
Thread Tools Display Modes
Old 18-08-2012, 02:53 PM   #1
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
another boost problem

So I took the boost guage off and the boost controller and it stopped over boosting on the highway problem now is that after about 4000rpm in third fourth or fifth it feels like the boost just stops as if there is no boost at all :S
rogerstrampoline is offline   Reply With Quote
Sponsored Links
Old 18-08-2012, 02:55 PM   #2
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
Like it boosts in first and second hard still like it did before but in third fourth and fifth it boosts hard until 4000rpm
rogerstrampoline is offline   Reply With Quote
Old 18-08-2012, 05:41 PM   #3
matty88
Junior Member
 
Join Date: Jan 2008
Location: S/E Suburbs
Car: 1991 TX3 KF
Posts: 83
What turbo?
matty88 is offline   Reply With Quote
Old 19-08-2012, 09:12 AM   #4
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
Standard vj20 with a ported wastegate
rogerstrampoline is offline   Reply With Quote
Old 19-08-2012, 12:40 PM   #5
TheMAN
Senior Member
 
Join Date: Feb 2010
Location: USA
Car: .
Posts: 2,623
still waiting for a pic of how you hooked all these things up....
__________________
Protege FAQ, the best 323/Protege/Mazda3 resource enjoyed worldwide for 10 years
TheMAN is offline   Reply With Quote
Old 19-08-2012, 04:15 PM   #7
project.r.racing
Senior Member
 
project.r.racing's Avatar
 
Join Date: Sep 2004
Location: n/a
Car: n/a
Posts: 10,929
what is that blue thing in place of the wastegate solenoid?

and i'm counting 1 too many vacuum lines (could be wrong on this one) i think it is the long blue one between the t-piece and intake manifold.

edit, just to add to this, the missing wastegate actuator should be plumbed into the pipe between the AFM and turbo. and the pipe from the t-piece should be plumbed into the pipe between intercooler and throttle body (i think).

Last edited by project.r.racing; 19-08-2012 at 04:21 PM.
project.r.racing is offline   Reply With Quote
Old 19-08-2012, 04:20 PM   #8
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
Blue thing is my boost controller and the long blue line is my wastegate line....which I'll be changing soon to my original setup....i had it just after the turbo but I bunged it and did this instead. Also do u think cuz i ported the wastegate that its now letting too much out under load?
rogerstrampoline is offline   Reply With Quote
Old 19-08-2012, 04:25 PM   #9
project.r.racing
Senior Member
 
project.r.racing's Avatar
 
Join Date: Sep 2004
Location: n/a
Car: n/a
Posts: 10,929
i don't think the wastegate is the issue, as you have gone from voer to under boosting.

i think you vacuum line setup it incorrect.
project.r.racing is offline   Reply With Quote
Old 19-08-2012, 04:28 PM   #10
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
Fair point...i might go to my original setup again cuz it had no problems except i just coulsnt see the boost it was running.
rogerstrampoline is offline   Reply With Quote
Old 20-08-2012, 12:13 PM   #11
DavoAust
Senior Member
 
DavoAust's Avatar
 
Join Date: Mar 2007
Location: Brisbane
Car: Red '93 3000GT / Black '08 Ninja 250R
Posts: 2,930
Send a message via MSN to DavoAust
Conventional setup:
- waste gate should be plumbed into the plenum. Not before it. You want it reading the pressure going into the cylinders, not the pressure before losses through the piping (good way to under boost)
- the boost gauge should also be running off the plenum
- the BOV vacuum source should the plenum
- fuel pressure reg (you'll have a rising rate fpr) should be a separate line again

This is a decent diagram of the vacuum line setup for a similar 4cy single turbo. Thats how you should run it.


I have no idea what brand/model of manual controller that is, i thought turbosmart but they haven't got that extra output line. I assume you're running the gauge off that?

I'd suggest 2 things straight up:
- If that silicon hose is too a small diameter (you'll want 3-3.5mm) or soft walled go get some normal vacuum line. Its cheap and reliable. If you have a split in the hose or it expands too much you can get momentary overboost as it expands/vents.
- Plumb the boost gauge back in ASAP. You'll need it to know whats going on.

Do you have a wideband yet? You might be running out of fuel at higher rpm & load. Or the waste gate might be opening early and flowing more with the porting.

I did notice:
- Is that silicon piping kinked before the AFM? Hard to tell from the photo but it looks like it. That can bugger up the readings if the airflow isn't smooth
- You've exhaust wrapped the downpipe. It'll eventually root the downpipe if you're running it hard or parking outside. They do a brilliant job of causing moisture retention if you leave the car for a few days and creating intense surface heat on the piping itself. If there's any gaps in the wrapping (it'll move/tighten over time) they'll create hotspots that can burn other stuff around them. Oil lines are a popular one, google exhaust wrap & engine fires . You're better off using heat sheilding on the sump/above the piping and HPC coating the dump pipe. Definately put something between it and the sump though
__________________
Understeer is when you hit the wall with the front of the car and oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall, torque is how far you take the wall with you.

'97 1.8L Hardtop
'93 3.0L TT 3000GT
DavoAust is offline   Reply With Quote
Old 20-08-2012, 04:08 PM   #12
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
That's exactly how my setup was and it still did it...tried a few vacuum lines too with density and size. It is a turbosmart single stage boost controller. For now I've put the guage bavk on to see if it overboosts again.....I was thinking with the porting it may be letting out excess air when it releases which could be causing this. In any case I'll be at dyno day may aswell hahaha
rogerstrampoline is offline   Reply With Quote
Old 20-08-2012, 04:10 PM   #13
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
It wouldnt be fuel or the silicone pipe as it was still hitting 14psi with that setup before I took the guage off
rogerstrampoline is offline   Reply With Quote
Old 20-08-2012, 04:44 PM   #14
derb
Senior Member
 
derb's Avatar
 
Join Date: Oct 2008
Location: Brisbane
Car: 1993 BG Astina GT-X
Posts: 1,822
I'm really at the end of my expertise here man, time for a performance tuner or something?
__________________
derb is offline   Reply With Quote
Old 20-08-2012, 05:39 PM   #15
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
Dyno day I think....boost guage is back on and at 4000rpm the boost goes from 10psi to about 5psi and stays there
rogerstrampoline is offline   Reply With Quote
Old 20-08-2012, 05:47 PM   #16
project.r.racing
Senior Member
 
project.r.racing's Avatar
 
Join Date: Sep 2004
Location: n/a
Car: n/a
Posts: 10,929
wastegate is letting out too much exhaust gases maybe. can it be set to open at a higher rpm?

Last edited by project.r.racing; 20-08-2012 at 05:52 PM.
project.r.racing is offline   Reply With Quote
Old 20-08-2012, 05:54 PM   #17
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
i was thinking that....but then after i ported it i drove it for a week and it was still holding 12psi all 1st and 2nd and then overboosting in 3rd gear +
rogerstrampoline is offline   Reply With Quote
Old 20-08-2012, 06:01 PM   #18
project.r.racing
Senior Member
 
project.r.racing's Avatar
 
Join Date: Sep 2004
Location: n/a
Car: n/a
Posts: 10,929
actually unplug the actuator from the vacuum line, block the end of the line and go for a spin. if it still boosts past 4000rpm, then you're heading in the right direction.
project.r.racing is offline   Reply With Quote
Old 21-08-2012, 07:03 AM   #19
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
Gonna search for leaks in bov line etc and recheck all pipes and clamps after work today and see how that goes then ill try the actuator unplugged if that doesnt work
rogerstrampoline is offline   Reply With Quote
Old 21-08-2012, 06:35 PM   #20
rogerstrampoline
AstinaGT Regular
 
Join Date: Apr 2012
Location: south brisbane
Car: 1993 BG Astina SP
Posts: 365
So today I changed half of my clamps and tightened some up some more and it helped slightly seconds is sweet it only drop to like 8psi now and third plus drops slower so doesnt feel like it brakes when it loses power as bad.....so I'm thinking maybe its a boost leak somewhere if me tightening and changing clamps made a slight difference
rogerstrampoline is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time now is 09:13 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
2001- 2010 AstinaGT