MAF setup questions (blow through??) need help!

P

pb4ugoout

okay, all of these questions have stemmed from my purchase of the DG Motorsports Ram Air Hood. I recently got the air box for the hood and I want to make that scoop functional. I currently have an Injen CAI, JoeP FPR, and a CustomMSP SMIC in use under my new hood. I have found that the only way to get my air filter into the box from DG is to cut it up so that I can move the MAF out of the way. This leads me to my questions. I don't want to cut up my Injen. It was expensive and I may want to sell it someday. Plus it involves cutting off a re-welding the nipple and the BPV pipe. I'm going to get hardpipes soon and I want to get information about the "Blow through setup". If I put the MAF on the Turbo to TB pipe then I won't have to cut up my Injen at all. The filter fits fine in the air box without the MAF. My other questions are a result of the MAF being moved. I would like to use a BOV instead of the stock BPV or a diffferent BPV. However with the MAF near the throttle body, where would I put the BOV? But I could also choose to just buy the Forge BOV that replaces the stock BPV. Would this cause problems with the MAF being where I want to put it? Does anyone offer pipes without a BOV flange? And if i ordered pipes with a flange and I used a BOV and then put the MAF next to it (not sure of location, before or after BOV) would i still need to run a dual-setup as in a bov and a bpv? ugh, this is gettting confusing and i really really appreciate anyones input.
 
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Turbo

They sell a turbo kit for the miata that uses a blow though maf set up. Are you are suggesting the same?

Keep the BOV close to the turbo, you can VTA if the BOV is before the MAF going into the TB, since the air is still unmetered at that point. But you can put the VTA BOV anywhere before the MAF...
 
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yea thats what i want to do but i'm wondering where i would put my bov. and what is VTA? and bump for more suggestions
 
pb4ugoout said:
yea thats what i want to do but i'm wondering where i would put my bov. and what is VTA? and bump for more suggestions

VTA = Vent To Atmosphere, BOV that are made/sold, such as JGS, FM , HKS, Greddy, Baileys, most of these are set up VTA but a few can be setup to recirculate. BOV's such as the Bosch or Nippondenso found on OEM applications usually recirculate. A recirculating BOV is very similar(if not the same) to your BPV (Bypass Valve).
 
so i'm not sure why i'm not getting much help but how bout this...does it really matter where the BOV goes??? does it matter where the MAF goes? what are the pros and cons of putting them in different places other than stock?
 
so i'm not sure why i'm not getting much help but how bout this...
does it really matter where the BOV goes???

Ideally you want it as close to the TB as possible.

does it matter where the MAF goes?

Yes and No

what are the pros and cons of putting them in different places other than stock?

You want the MAF to measure all the air that is entering the intake manifold. If you plan on exceeding 15 psi then you'll want the MAF before the turbo.

Air cleaner>Maf>compressor inlet>compressor outlet>IC>Pipe>BOV>TB
or
Air cleaner>compressor inlet>compressor outlet>IC>pipe>BOV>maf>TB
or
Standalone and map sensor....no MAF

If you want to recirculate then the air you are recirculating needs go from the boost side of the turbo to infront of it.
Air cleaner>Maf>discharge from BOV>compressor inlet>compressor outlet>IC>Pipe>BOV(1" hose back to behind Maf)>TB
basically if you recirculate all you air needs to either be metered or non metered, don't have the BOV 'loop around the maf', because some BOV's are open @ Vac and this will cause a bad idle and other driveability issues.

Confused yet?
Can you take a pic of what you are planning? just a layout on the floor would give a good visual.

not sure why no one else has chimed in, maybe there are not that many DIY turbo's around? I spent a month of reading here before posting, there is alot of 'static traffic' here...
 
if only you were a day earlier. i started another post in another section and got more responses and a lot of help. i appreciate your help tho. had i had it yesterday i wouldn't have needed the other post. you put it very plainly and it was easy to understand. i'm going to get hardpipes and it will make my life easier but i'm gonna put an MAF about 8" from the throttle body. then i'm going to put a BOV in roughly the same place as the stock BPV nipple on the turbo to IC pipe. i'll also have to plug that tube on the injen. that way my system will work better, i won't have a turkey, and i'll be able to use my spiffy air box with the big hole in my hood. thanks for you help tho man

p5T said:
so i'm not sure why i'm not getting much help but how bout this...
does it really matter where the BOV goes???

Ideally you want it as close to the TB as possible.

does it matter where the MAF goes?

Yes and No

what are the pros and cons of putting them in different places other than stock?

You want the MAF to measure all the air that is entering the intake manifold. If you plan on exceeding 15 psi then you'll want the MAF before the turbo.

Air cleaner>Maf>compressor inlet>compressor outlet>IC>Pipe>BOV>TB
or
Air cleaner>compressor inlet>compressor outlet>IC>pipe>BOV>maf>TB
or
Standalone and map sensor....no MAF

If you want to recirculate then the air you are recirculating needs go from the boost side of the turbo to infront of it.
Air cleaner>Maf>discharge from BOV>compressor inlet>compressor outlet>IC>Pipe>BOV(1" hose back to behind Maf)>TB
basically if you recirculate all you air needs to either be metered or non metered, don't have the BOV 'loop around the maf', because some BOV's are open @ Vac and this will cause a bad idle and other driveability issues.

Confused yet?
Can you take a pic of what you are planning? just a layout on the floor would give a good visual.

not sure why no one else has chimed in, maybe there are not that many DIY turbo's around? I spent a month of reading here before posting, there is alot of 'static traffic' here...
 
What about this: <Click>
would the BOV give the car stalling issues due to the BOV sucking air back though the MAF during blow off<CLICK>
 
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MazdaSpeedSter said:
What about this: <Click>
would the BOV give the car stalling issues due to the BOV sucking air back though the MAF during blow off<CLICK>

Actually the car would give you stalling issues @ idle if the BOV was open @ idle, allowing unmetered air past the MAF, Most MAF cars don't like that. Most BOV's are open under vac and closed under boost, some like the Baileys are a pull type that open only when transisting between boost and vac, stay closed @ vac, such as idle, and stay closed during boost...
 
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