Help me figure this out (MRT Boost Cut Defender)...

That spinning thing that makes all of the cool noises. OE and Aftermarket.

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Fkyx
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Help me figure this out (MRT Boost Cut Defender)...

Post by Fkyx »

Alright. Firstly, it's called a Boost Cut Defender, but in fact, it's a fuel cut defender. Second, I emailed MRT about a manual for it so I could read about it, and they sent me an old version of the documentation, which they say should work (application for WRX).
http://docs.google.com/Doc?id=d532khn_11ddxw9gf9

So I'm reading this and the term "boost sensor" comes up a lot. Where is *our* "boost sensor"?

Next, I'm thinking about how mine is already installed:
Image

This begs the questions: 1. Is the MAF our "boost sensor"? or 2. Did the person who installed this do it wrong?

Even if #1 is true, I still think it was installed incorrectly. I never ran the boost past 12lbs, though... so I have no idea if the FCD was doing its job. Looking at the wiring job, though...

I'd love to get this figured out so I could reinstall it, and make it look clean. I'll throw together a diagram of the current install if anyone needs it. Thanks!
Matthew aka F[b][color=red]k[/color][/b]yx
1991 Legacy Sport Sedan "Jillian" - [url=http://bbs.legacycentral.org/viewtopic.php?t=39548]EJ20G swap[/url]
PhyrraM
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Post by PhyrraM »

Some cars will fuel cut at a certain MAF voltage. This is only reliable if the car is completely stock.

Our car do not cut on a MAF Voltage, but on a MAP voltage. So, for a WRX/Legacy SS installation it is wrong.

You should be able to follow the instuctions thay gave you without any problems.
'93 Winestone SS Auto, '91 Pearl White SS.
'93 Pure White SS EJ20G slanty intercooled, SIDESWIPED! In stasis.
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Fkyx
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Post by Fkyx »

Alright. So the FCD needs to be relocated?
Matthew aka F[b][color=red]k[/color][/b]yx
1991 Legacy Sport Sedan "Jillian" - [url=http://bbs.legacycentral.org/viewtopic.php?t=39548]EJ20G swap[/url]
PhyrraM
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Post by PhyrraM »

I, personally, would place it under the dash near the ECU. This,however, is a very tight spot and is a royal PITA to work in.

It can be safely place near the MAP under the hood. Hell, it lived there for who knows how long as it sits now, right?
'93 Winestone SS Auto, '91 Pearl White SS.
'93 Pure White SS EJ20G slanty intercooled, SIDESWIPED! In stasis.
'94 FWD and '95 AWD Laguna Blue SVXs.
2017 Pure Red BRZ Limited w/Performance pack
Fkyx
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Posts: 842
Joined: Fri Nov 02, 2007 5:30 am
Location: Albany, OR

Post by Fkyx »

Well, MRT claims it's fully waterproof, and that it's meant to be installed under the hood... so I might leave it. Regardless, I need to "redo" the installation... so I'm not sure what I'll do.
Matthew aka F[b][color=red]k[/color][/b]yx
1991 Legacy Sport Sedan "Jillian" - [url=http://bbs.legacycentral.org/viewtopic.php?t=39548]EJ20G swap[/url]
biggreen96
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Post by biggreen96 »

well you should definitely get it hooked up to the right sensor! I think at this point an under the hood install would be fine. But yeah, it will work much better when it's intercepting map voltages and not maf voltages.


I think the stock location is between the airbox and the strut tower it looks similar to this, with only one vacuum/boost hose going into it. http://www.otemotorsports.com/images/HK ... versal.jpg

good luck.
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