BOV + MAF

ModMX3 - (Carmaster2005) · May 7th, 2006, 11:54 am

hey everyone, this question has been asked befor, but not quite sure about it. If your using a BOV befor the MAF and venting it to the atmosphere , ive read it WONT cause a problem with your idle or running rich/lean. Is this true . woulnt the MAF still read a loss in air flow ? thanks.

Bochek · Post by **Bochek** » May 7th, 2006, 6:24 pm

it is impossible to use the bov before the maf.

maf has to be before the turbo, and bov has to be after the turbo.

Bochek

ModMX3 - (Carmaster2005) · May 8th, 2006, 9:14 am

Thanks! is this the setup you have ? Filter -> MAF -> Turbo -> IC -> BOV -> TB . ive seen this setup befor dose it work ok / Idle fine.

fieromx3 · Post by **fieromx3** » May 8th, 2006, 11:59 am

umm thats not actually true there bochek u can use a maf AFTER the turb with the BOV BEFORE the maf unless you are using the stock maf from the 4 cylinder use that before the turbo. also i dont think u wanna vent the BOV to the atmosphere with the bov after the maf it can cause problems when u let off the gas from making boost. its like this on my ex-dsm that it must be re-circulated back to the intake so it dont run extremely rich when u let off the gas id dunno maybe these cars can run vented without problems?? correct me if im wrong.

and yes modmx3 thats good alot of set are like that

hotsiit · Post by **hotsiit** » May 8th, 2006, 12:34 pm

hey Modmx3...the way you listed, is how I have my setup running. I also have the BOV recirculated back into the intake tract. it runs fine this way, and i have been boosting 9psi for a few years now. later

ModMX3 - (Carmaster2005) · May 8th, 2006, 1:49 pm

Nice setup hotsiit . but how did you run the tubing for the intercooler ? I was checking it out today and could not figure out how in the world to run 2.5 inch lines through to the front. I mean did you have to drill out part of the frame ? im trying to avoid running them under the radaator as they will be to low to the ground. Also can you still hear your BOV from inside the car with it being recircuated ? I love the souund of a BOV (as most do) but i dont want to sacurfice performance forr it. Thanks !

ModMX3 - (Carmaster2005) · May 8th, 2006, 1:51 pm

Nice setup hotsiit . but how did you run the tubing for the intercooler ? I was checking it out today and could not figure out how in the world to run 2.5 inch lines through to the front. I mean did you have to drill out part of the frame ? im trying to avoid running them under the radaator as they will be to low to the ground. Also can you still hear your BOV from inside the car with it being recircuated ? I love the souund of a BOV (as most do) but i dont want to sacurfice performance forr it. Thanks !

Joey's mx · Post by **Joey's mx** » May 8th, 2006, 6:40 pm

ok so when running a stock MAF from a dohc b6 with a open atmosphere you should run the MAf between the filter and the turbo?? Would runnign the Maf between the throttle body and the blow off valve hurt it?? This seems to be a big question because i asked a couple months ago and poele where saying that you can not run the maf between the throtle body and blow off valve when using an open atmosphere blow off valve!!

So i would really like to know if you can run the MAf between the turbo and filter with an open atmesphere blow off valve??

I have seen it done both ways also so what is up??

ariesdude · Post by **ariesdude** » May 8th, 2006, 7:29 pm

I do not know much about turbos - but one question that's nagging me is - The MAF also has a temperature sensor for the incoming air - the ecu uses that to adjust air/fuel mixture - so if it sits before the turbo - it will register ambient temperature whereas the actual air going into the engine might be a different temperature because of the turbo/IC - wouldnt that lead to tuning/detonation problems? Maybe a good tuner could map it so that the ecu "guesses" the correct value most of the time - but for noobs wouldnt it make sense to have the actual temperature/flow going into the TB - just to make life a bit easier.

fieromx3 · Post by **fieromx3** » May 9th, 2006, 12:20 am

Joey's mx wrote: Would runnign the Maf between the throttle body and the blow off valve hurt it??

u can run the maf between the turbo and throttle body but the blow off valve needs to be mounted before the maf.

cjthor · Post by **cjthor** » May 9th, 2006, 1:32 am

OR use a super AFC which can compensate for the blow off into atmosphere! Thats what im doin. car runs fine. My car goes -air filter-MAF-turbo-intercooler-bov-tb.

Bochek · Post by **Bochek** » May 9th, 2006, 7:32 am

sence when can you run the maf after the turbo. i allways thought it had to go before the turbo.

Bochek

osargeant · Post by **osargeant** » May 9th, 2006, 8:10 am

I am also running the exact setup as cjthor, with a TurboXS Type S BOV which vents to atmosphere and it works fine. Running 10+ psi with no problems.

fieromx3 · Post by **fieromx3** » May 9th, 2006, 11:26 am

u always could bochek u can use it either before or after the turbo

Bochek · Post by **Bochek** » May 9th, 2006, 2:57 pm

hmmm so the compressed air wont affect its mesurement on vollume of air?

interesting. new idea i got brewin then.

Bochek