TMIC, BOV and AOS decisions decisions

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xise
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TMIC, BOV and AOS decisions decisions

Post by xise »

So I have a 93 SS I just got running again and I would like to install an 07 WRX TMIC I have. I also bought an HKS ssqv bov, but all the setups I see run the TMIC using the stock BPV with the one line going to the IM and the other going to the crank case....my question is can I just put an air filter for the crank case vent and use the one vac line to the IM OR can I install the grimmspeed AOS and use that port on the crank case for the AOS...

seems like there are a lot of possibilities, I would like to avoid using the AOS if possible I want it for another subie but if I can't just put a small filter on that crank breather I guess I would have to use it...any suggestions??
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1993 Legacy Sport: Sedan Sex Panther-R.I.P. @ the boneyard
1991 Legacy L Wagon: Sex Panther II
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Legacy777
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Re: TMIC, BOV and AOS decisions decisions

Post by Legacy777 »

The bottom line is that your current setup is a closed loop setup from the MAF sensor to the intake and even the crank case breather system.

Going to an open loop setup where you have crank case vents or turbo bypass/vents that don't back into the intake will cause metered air to escape and can affect your air-fuel-ratio.

It is generally a good idea to run a bypass valve vs. blow off valve on MAF based cars. Some will run BOV's with ok success. You end up with momentary lean conditions when lifting off the throttle. The BOV needs to be adjusted properly so that it does not allow air to escape at idle.
Josh

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xise
Third Gear
Posts: 576
Joined: Sun Aug 01, 2010 11:17 pm
Location: Rhode Island

Re: TMIC, BOV and AOS decisions decisions

Post by xise »

good to know, I though that if I had the air oil seperator along with the bov I could make it work b/c instead of ele iminating the recirc hose for the BPV I could use the hose from the AOS to complete the loop. That way everything will still be intact, and I guess I would just have to monitor the air escaping @ idle like you said.

All I can do is hook it all up and see how well it works, i'll report my findings once it is running
2004 Impreza 2.5RS Fränkenpreza Daily Driver
1993 Legacy Sport: Sedan Sex Panther-R.I.P. @ the boneyard
1991 Legacy L Wagon: Sex Panther II
2005 Outback XT Turbo grocery-getter Wife's Daily Driver
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