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13 Forester XT 4EAT
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4,168 Posts
Discussion Starter #3
It sure is. They are expensive as hell. I think they are in Australia or Japan.
 

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Premium Member
2012 GTI DSG 6-speed
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1,463 Posts
Sounds (and looks) like a manual boost controller intergrated into the wastegate actuator. Kind of pricey though.
 

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Premium Member
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2,132 Posts
Looks more like a normal (though probably high quality) actuator with a special adjustable arm.
 

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2006 RX8
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423 Posts
Looks like a full wastegate vacuum canister replacement with adjustable arm for fine-tuning the boost. Probably has a heavier internal spring than the stocker to provide a more specific and more hardline wastegate release. If you run a stock wastegate actuator without the factory boost controller, it will release at around 7-8psi static setting if I remember correctly. This would be a hose running directly from the turbo compressor outlet nipple directly back to the wastegate actuator canister.

As most already know, the FBC bleeds off air to keep the wastegate tricked into believing it has not exceeded the 7-8 psi of the baseline pressure setting (7-8psi) of the wastegate canister /actuator. At low speed the FBC doesn't bleed any pressure and instead allow the stock actuator spring to kick in resulting in lower boost around the 7-8psi range. A heavier spring would ensure that the boost would be higher in low (1st/2nd gear) gears as the static spring pressure would hold up to perhaps 12-13psi baseline with no FBC bleed-off. Overall I would imagine the overall performance would be more reliably held boost with a crisper actuation overall. Danger would be related to the OL/CL issues and the increased boost pressure creating lean conditions prior to cross-over.

Other than that, I could definitely imagine using an upgrade like that. Some people have even installed extra external springs to make the static boost pressure release a higher number. Sort of a low-cost DIY sort of deal.

Jeff
 

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BLUE WASABI, (#2 Info Provider)
2008 SG Model D
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9,051 Posts
N10S said:
Danger would be related to the OL/CL issues and the increased boost pressure creating lean conditions prior to cross-over.

Jeff
But w/ that said about the open and closed looping, if you get a retune for your ECU, you A/F should be fine, correct?
 

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2006 RX8
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423 Posts
Based on my discussions with Cobb (AP), Vishnu (Ecutek), and with TXS(Utec), it sounds like each has a fix for the OL/CL problem. There was another company that offered a standalone device that would alter the cross-over as well. Sort of like a boost cut defender sort of deal I think.

Overall, even with the OL/CL issue out of the way, introducing a different wastegate canister would change the dynamics of any "canned" em solution and would require custom tuning to optimize the use of a unit such as the one offered by AVO.
 

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BLUE WASABI, (#2 Info Provider)
2008 SG Model D
Joined
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9,051 Posts
N10S said:
Based on my discussions with Cobb (AP), Vishnu (Ecutek), and with TXS(Utec), it sounds like each has a fix for the OL/CL problem. There was another company that offered a standalone device that would alter the cross-over as well. Sort of like a boost cut defender sort of deal I think.

Overall, even with the OL/CL issue out of the way, introducing a different wastegate canister would change the dynamics of any "canned" em solution and would require custom tuning to optimize the use of a unit such as the one offered by AVO.
So that is a "Yes" to my question?
 

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2006 RX8
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423 Posts
Yes to the diminished concern that the OL/CL issue would no longer be a threat to creating a lean-run condition. No to the fact that the new actuator with different boost charactersitics could still create some problems with A/F ratios until it could be custom tuned.

With the old WRX's, the OL/CL was not an issue and the cars ran pretty rich in stock trim so you could safely muck around with an MBC or EBC as long as your boost didn't exceed the capabilities of the stock injectors which was around 14-15 psi. More boost within that aforementioned range leaned out the fat fuel condition and although it wasn't a perfect solution, it did make decent reliable power increases for a low mod investment.

Engine management solutions typically remap fuel, timing, and boost for optimizing performance. There is a lot more power available by running leaner fuel maps, but the downside is high egt's, and melted engine parts if you suddenly decide to introduce a standalone on top of an existing tune. With that in mind it stands to reason that the likelihood that you might still run into a lean-run condition is more prevelant when running a stand-alone boost controller (MBC, EBC, or even the AVO wastegate actuator) with an EM tuned car, than if it was a stock ECU map which would be mapped with much fatter fuel curves.

I know its a yes/no answer, but thats what it is in my eyes.
 

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Premium Member
04 XT
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733 Posts
Yes but you really need a tune because that actuator is going to all kinds of things the ECU isn't expecting. Like taper, overshoot and minimum pressure.
 

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27 car gear
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846 Posts
I've had that when I had a iON Performance stage 1 turbo. A re-worked stocker. Massive porting, and a few impeller changes. The next stage up was the higher rated actuator IIRC. I managed to get my hands on one from another member years back, and made it work for only a hair less then a new one.

So instead of a 7lbs spring like the stocker, you now have a 14-15lb spring. I never really tuned anything for it, I saw it as a mechanical boost controller if anything. I then used an Apex AVCR to get roughly 17PSI out of the midrange, and taper back down to 14psi near redline.

I'm sure it had it's applications. The stock turbo was not it though :( Perhaps if you had issue where the flapper would open up, then this would be ideal.

This on a '02 WRX.
 
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