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Old 04-21-2009, 10:33 PM   #1
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Default BOV Location on Intake Manifold

I'm adding a BOV to a stock Greddy kit. My question has to do with location, i.e., near the throttle plate or near the compressor outlet? The prefabbed kits (BEGI) seem to vent near the throttle plate. Anyone know whether there is a preferred location and the theory behind it?

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Old 04-21-2009, 10:41 PM   #2
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Near the throttle plate is a good location. I'm devising a theory.
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Old 04-21-2009, 11:06 PM   #3
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Hey look, a fighter guy! Woohoo, somebody who will listen to me!!!

The correct answer is: it doesn't matter. You can put your BOV anywhere in the charged system, starting at the first coupler exiting the compressor, all the way to the coupler at the throttle body, welded to the pipes, welded to the IC, t-coupler, etc... If you're talking about absolute last .0001 percent of improvement in performance, then closer to the IM the better. It's more important to have a clean and functional recirculated (in your case) setup. I'm curious how you're going to mount it on the stock plastic crossover pipe, and how you're going to recirculate it? Most people upgrade the OEM plastic crossover to a single-piece metal tube... how are you doing it?
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Old 04-21-2009, 11:47 PM   #4
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I chose to put mine very close to the throttle body not only because it is generally agreed that that is the optimal (though it doesn't matter much) place to put it but also because it is a unit with moving parts inside, and away from the heat of the turbo can only be a good thing for it. Yes it will make your recirculation plumbing longer, but I'd rather do that than have the valve right by the turbo so I could have a really short recirc. tube... plus, eventually just about everyone ends up getting a standalone ecu because they just should... so then you won't need to recirculate and that won't matter.
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Old 04-22-2009, 01:39 AM   #5
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Originally Posted by samnavy View Post
Hey look, a fighter guy! Woohoo, somebody who will listen to me!!!
What about me......
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Old 04-22-2009, 01:47 AM   #6
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hornetball: been there, done that. Take off the stock boxy plenum thingy that connects to the stock crossover by the throttle body. Its just there to absorb some random harmonics that disrupt airflow with the stock intake setup, which obviously you don't have. Then place a small piece of pipe with the same outer diameter as the inner diameter of that connection, and clamp a BOV to that. I bought a used bosch unit for cheap on ebay. The piece of pipe is in there to prevent crushing that connection when you clamp it down, since it is just thin plastic.

Also, the accordion part of the stock crossover will expand with the boost pressure. To keep it from expanding too much, put some snug zip ties (black for stealth) in the crevices of the accordion section. I'm not sure if it helped with any performance or explosions, but it nearly eliminated the expansion.
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Old 04-23-2009, 01:22 AM   #7
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Thanks Curly. Great advice to get going quickly.

Sam, my progress is sporadic as I'm in the middle of a move, house remodel, company merger, etc. I have 1" and 2.5" 6062 aluminum tubing that I plan to use for a permanent intake (1" for nipples and recirculation, 2.5" for the main intake). For now, I'm using the stock intake while waiting to see if the "more boost, more power" bug hits . . . which would lead to an IC, clutch, etc. It seems to hit most on this forum. I doubt I'm immune.

I flew 18s out of Cecil Field and USS Saratoga. Picked up a brand new Lot 10 C model from the factory and flew it in Desert Storm a couple of years later. That should date me.
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