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 Post subject: over boost?
PostPosted: Sun May 12, 2013 4:55 pm 
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Clubman

Joined: Mon Dec 31, 2012 11:34 pm
Posts: 51
Location: yeovil
Car Model: None
Right hi guys. Basically my cars trying to run at 24psi of boost and not actually accelerating to match. It should be at 15psi. Adjusting the manual (spring and ball bearing) boost controller has no affect atal on boost levels. Also the wastegate is free. Obviously can't tell if its moving or not as can't look.under bonnet on.the move. Police frown om that. Umm I've checked for splits and leaks. Using carb cleaner and not found any. All pipes are tight. For intercooler and as far as I can tell the turbo bearings have minimal play. So any other ideas to source and sort this problem would be amazing. Its a 90 plate (G reg) st185 3sgte engine. With mongoose full stainless exhaust. 3inch decat. Manual boost controller and forge external actuator. Many regaurds jamie.


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 Post subject: Re: over boost?
PostPosted: Sun May 12, 2013 5:02 pm 
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Joined: Thu Jul 14, 2005 12:44 pm
Posts: 4067
Location: drinking devil fuel
Car Model: ST205
You can test the actuator with a foot pump or bike pump and some ingenuity


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 Post subject: Re: over boost?
PostPosted: Sun May 12, 2013 5:18 pm 
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Group B
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Joined: Sat Sep 02, 2006 3:13 pm
Posts: 3679
Location: Bournemouth
Car Model: None
Try removing the manual boost controller and plumbing direct to the actuator from turbo.

If the wastegate isn't opening it's one of the following reasons:

Blockage/restgriction in pipe from turbo to actuator (no air to push wastegate open)

Leak from actuator, e.g. split / open hose from other port of wastegate or split diaphragm in wastegate. (carb cleaner won't show up these leaks as air will come outwards)

Mechanical jam of wastegate mechanism.

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 Post subject: Re: over boost?
PostPosted: Mon May 13, 2013 9:27 am 
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Joined: Wed Jul 13, 2005 12:06 am
Posts: 4743
Location: Perth, Western Australia
Car Model: ST205
Sound advice above. Follow that and let us know what you find.

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1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
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 Post subject: Re: over boost?
PostPosted: Tue May 14, 2013 12:42 am 
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Clubman

Joined: Mon Dec 31, 2012 11:34 pm
Posts: 51
Location: yeovil
Car Model: None
Apparently afrer some lengthy phone calls and severe head scratching. The guys at tcb reckon diaphragm split or damage as I can open the wastegate with relative ease using a stubby flat blade screwdriver. New actuator hunting now. I have a forge one in place and its lasted 8 years apparently with no.maintenance if not longer. So considering repairing or replacing the broken parts. Any ideas on parts sourcing? Contact forge themselves the logical one. Unless someone can recommend any better alternatives?


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 Post subject: Re: over boost?
PostPosted: Tue May 14, 2013 9:14 am 
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Group N

Joined: Fri Apr 06, 2012 6:13 pm
Posts: 406
Location: Weymouth southwest dorset
Car Model: None
If u can push actuator with screwdriver its gubbed!!

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 Post subject: Re: over boost?
PostPosted: Wed May 15, 2013 2:11 pm 
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Clubman

Joined: Mon Dec 31, 2012 11:34 pm
Posts: 51
Location: yeovil
Car Model: None
Gubbed?


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 Post subject: Re: over boost?
PostPosted: Wed May 15, 2013 7:29 pm 
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Club Staff
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Joined: Wed Jul 13, 2005 12:06 am
Posts: 4743
Location: Perth, Western Australia
Car Model: ST205
Er, something doesn't compute here. If the actuator is fubared then you wouldn't be seeing 24psi boost! Have you removed the actuator and tested it as described above?

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp


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 Post subject: Re: over boost?
PostPosted: Wed May 15, 2013 8:38 pm 
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Joined: Thu Jul 14, 2005 12:44 pm
Posts: 4067
Location: drinking devil fuel
Car Model: ST205
It might if the diaphragm has torn. Pumping it up would soon highlight that


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 Post subject: Re: over boost?
PostPosted: Fri May 17, 2013 12:05 am 
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Clubman

Joined: Mon Dec 31, 2012 11:34 pm
Posts: 51
Location: yeovil
Car Model: None
Reckon its torn diaphragm hopefully fitting a new actuator and pull mine apart Saturday to see what's going on. Think its torn diaphragm but not sure yet.


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 Post subject: Re: over boost?
PostPosted: Fri May 17, 2013 1:52 pm 
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Joined: Wed Jul 13, 2005 6:54 pm
Posts: 3484
Location: On Top
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if you are usinf a forge actuator i think they come apart...

I know you can buy new different ratings of spring so maybe they can supply a new diaphragm?
http://www.forgemotorsport.co.uk/conten ... ct=FMAD116

EDIT:- They can - there are 2 types so you will have to call them to identify which the GT4 actuator uses.

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 Post subject: Re: over boost?
PostPosted: Thu May 30, 2013 12:08 pm 
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Clubman

Joined: Mon Dec 31, 2012 11:34 pm
Posts: 51
Location: yeovil
Car Model: None
After a few weeks of head scratching and not being able to log in. Got actuator off. And as above I've called forge. Hopefully get it this weekend. And have the monster job of changing it "again" lol took ages last time. Also replaces my ball and spring type boost controller for an ebc Gizzmo ms-ibc. Anything else anyone can think of would be appreciated


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