Rev3 Turbo Overboosting help. *UPDATE* - DP off

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adam3442
Posts: 606
Joined: Wed Nov 02, 2005 3:11 pm

Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by adam3442 »

Gents,

Hoping for some help. Car was going for mapping and had a funny boost issue. Basically, the car was making actuator pressure (0.5 bar est) then it would pause making boost, then would shoot up to 1.6 bar. The mapper suggested that the actuator could be catching which seems plausible having a look around here.

Got the car back, have whipped the heat shield and turbo to intercooler pipe off. Hooked up my compressor and checked the movement of the actuator. I've taken a video below, whilst it looks ok to me I'm not really sure what it should look like.

Is there anything else I should be looking at? All the vac lines to and from the actuator, turbo and boost controller are fine.

Car is a rev3 turbo with Blitz K1-380V (CT20B with BW internals) and early Berk downpipe.

Is my compressor sending too much pressure to check properly? Is there a better way to check?

http://sendvid.com/oo0al4gr?secret=081e ... cc8f15f4a5

Thanks in advance!
Last edited by adam3442 on Sat Oct 27, 2018 7:31 pm, edited 1 time in total.
almeida1234
Posts: 450
Joined: Sun Aug 15, 2010 12:48 am
Location: west sussex

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by almeida1234 »

Just make sure actuator is not catching the inner of decat.
almeida1234
Posts: 450
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Location: west sussex

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by almeida1234 »

This link will explain
https://youtu.be/ku1MwZZ3_Fw
adam3442
Posts: 606
Joined: Wed Nov 02, 2005 3:11 pm

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by adam3442 »

Thanks bud! Turbo off time or boroscope up the downpipe?
simpson_eh
Posts: 633
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Location: south wales

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by simpson_eh »

nope just the turbo downpipe no need to take turbo off, you should be able to see if the wastegate catching downpipe
If you see an MR2 with a raised engine cover, the bottom line is it's probably faster than your car.
rgb
Posts: 237
Joined: Sun Sep 13, 2009 9:02 am
Location: somerset

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by rgb »

can you set your compressor to 10psi and see if it opens . if you put full pressure into the accuator it may still work even if the accuator is knackered .did it work before cause a wastegates not going to just
start catching
adam3442
Posts: 606
Joined: Wed Nov 02, 2005 3:11 pm

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by adam3442 »

So gents, whipped the downpipes off today, when I say whipped, I mean swore a lot, got cold and bruised.

But here she is, I can't see anything alarmingly obvious but has started to grind the flange back to the same diameter as the gasket to rule it out. Can anyone else spot anything obvious I have missed.

To remind you, the mapper said he attached a hand pump to the actuator, you could see it move, then stop then free up and move again. I don't have a hand pump and my compressor opens and closes it with ease.

It would be great if someone could take a look. I also notice the Berk DP (one of the first) has a crack on one of the welds so I have to tack that up tomorrow. Could the crack cause the over boost?

Image

Image

Image

Image

Image

I have another video of the waste gate opening with the DP off if people want to see that to help?

Thanks in advanced for any help. [/img]
rgb
Posts: 237
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Location: somerset

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by rgb »

I cant see any mark where the wastegate is hitting the downpipe. I had similar issues and it was because the wastegate hinges in a metal bush and it was loose in the turbo making it stick it had to be spot welded. I recon it a boost controller issue . see what it does with the boost control turned off. id also get a regulator for your compressor so you can set it to 13psi and connect it to your air pipes then spray them with soapy water to look for leaks.
adam3442
Posts: 606
Joined: Wed Nov 02, 2005 3:11 pm

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by adam3442 »

It was the same with the boost controller disconnected and the actuator hoses blanked. As in running only actuator pressure.

The arm seems to move ok. It's a really odd one 😔
almeida1234
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Location: west sussex

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by almeida1234 »

Two screws holding the actuator arm not loose or misaligned?
androo007
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Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by androo007 »

Did this behaviour happen before mapping? What rpm does it shoot up?
adam3442
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Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by adam3442 »

Prior to mapping she was laid up for about two years and has been changed significantly since then. Last time I drove it, on actuator pressure it wasn't going beyond 0.5 bar. And mapping was literally getting her setup to run. She's had a COP conversion, water meth, bigger injectors etc etc etc. So she was in for mapping to be setup and sorted.

Turbo is a blitz k1-380v, and a profec b boost controller but even when that's disconnected she has the same behaviour.
adam3442
Posts: 606
Joined: Wed Nov 02, 2005 3:11 pm

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by adam3442 »

almeida1234 wrote:Two screws holding the actuator arm not loose or misaligned?


I will check.

I'm thinking about buying a new actuator just to rule it out.
adam3442
Posts: 606
Joined: Wed Nov 02, 2005 3:11 pm

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by adam3442 »

Ok, so update time, I have clearance the DP even though there were no signs of contact, IO have fitted a forge actuator and adjusted the preload correctly, it is still overboosting.

I am using a Jun intake, BERK DP and BERK exhaust, I also have a G4+ PnP. The stock boost control is disconnected and the car is set to run actuator pressure which should be around 1.2/1.3 bar of boost.

Does the Link PnP need the stock boost control connected, clutching at straws with that one.

It seems I can't bleed enough boost off when it gets on it, any suggestions, please!?
rgb
Posts: 237
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Location: somerset

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by rgb »

I still recon its a boost controller issue . accuator pressure with a 12 psi spring wont make 12psi boost pressure it just starts to work at 12psi and its too late by then. have a look at mr2 exhaust restrictor which I was going to do but I finally got my boost control set right . ive got a forge accuator and a greddy e01 and it boosts perfect but it took years to set. at least your turbos good.
androo007
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Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by androo007 »

You should be using a decent 3 port solenoid.
SonicSW20
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Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by SonicSW20 »

What happens if you run it with the port on the turbo outlet connected directly to the actuator?
adam3442
Posts: 606
Joined: Wed Nov 02, 2005 3:11 pm

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by adam3442 »

Gazza_DJ wrote:What happens if you run it with the port on the turbo outlet connected directly to the actuator?


All tests have been done like that.

Currently the turbo is off, the waste gate is being ported to allow a bit more gas to flow, I've reduced the actuator spring so it bleeds boost quicker. If that doesn't work then we will try it with the boost controller to see if that makes a difference.

I don't see how it can as if the actuator can't bleed boost off and run actuator pressure, how does a solenoid help it can only open the actuator if there's enough pressure by which point there's too much... Genuine question, this is new territory for me!

I want to avoid a restrictor in the exhaust, it's counter productive, if it gets to that point the turbo will come off :lol:
SonicSW20
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Joined: Mon Nov 29, 2010 7:54 pm

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by SonicSW20 »

Adding the boost controller into the loop just introduces another variable, don't do that until you have it running at actuator pressure. As you say, all the boost controller can do is add boost over what it will run on actuator only, it cannot reduce boost below that point.

Wastegate porting will help, but it may just be compensating for an underlying issue.

What ECU are you running with this setup? You've mentioned mapper so I assume aftermarket? has it ever ran correctly with this turbo, and if it has, what has been changed since then?
rgb
Posts: 237
Joined: Sun Sep 13, 2009 9:02 am
Location: somerset

Re: Rev3 Turbo Overboosting help. *UPDATE* - DP off

Post by rgb »

you need a boost controller why don't you try it with the waste gate tied open and see what it does it will have massive lag and make full boost at about 6000 revs but will it over boost by the time you've sorted it youll be an expert
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