Question regarding FFIM with Bosch bypass valve.

suprafredde

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Apr 21, 2005
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Hi all.

FFIM almost done.
Stock ecu so no venting to atmosphere, not for me atleast.
If done right I have to weld a small alu pipe just before the tb and run a 20-22 mm hose all over the engine, or under to the pipe before the turbo.
I dont like this at all becuse in the near future the lex afm will be removed.

The Bosch bpv sits on the turbo intake pipe.
How "bad" would it be to just run a hose down to the pressure pipe going between turbo and IC?
That pipe is mild steel and I can cut/weld that myself.

suprafredde
 

toyotanos

What will we break today?
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Nov 29, 2008
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Coon Rapids, MN
You can put the pressure side of the BPV in between the turbo outlet and intercooler, but its not ideal. Ideally you would have the BPV as close to the throttle body as possible to limit transition time from boost-vacuum-boost.
The atmosphere side of the BPV has to be in between the AFM and turbo inlet.

From what I'm reading from yo it sounds like you're thinking right, but you'll need to clarify where yo're tapping into the intake system for the best results from us :)
 

suprafredde

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Apr 21, 2005
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"The Bosch bpv sits on the turbo intake pipe."
Just to clarify, between afm and turbo inlet just like stock.

I know that the bpv is open during manifold vacuum conditions.

I thought about using a bov, just to make things easier but the stalling/rich condition, isnt for me.
Some say it works, I dont care about that, its metered air.

Close to TB is ideal no arguments there. But Im auto so responce on-off throttle isnt all that important.

Looks like my thoughts where accurate, but will the bpv handle the hot air since its before the IC?

Made a nice pic too :icon_bigg

suprafredde
p1849431_1.jpg
 

toyotanos

What will we break today?
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Nov 29, 2008
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Yep, looks functional. Just make sure the pressure side of the bpv is exposed to the boost and not vice-versa. I haven't used a bosch unit, so I can't comment on its proper orientation.
 

suprafredde

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Apr 21, 2005
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Thx.
On the drawing the bpv is connected as its supposed to be, just like I remembered from my old car.
Checked the net also. I hope the diaphram will handle the heat.
My next question is will one valve be enough since the air coming from the turbo is pretty hot thus having more volume compared to post IC?

suprafredde