It's better to place the maf between the TB and the BOV, because this way you can vent all you want and not having any problems with stalling/running rich. I really don't see a point in placing the BOV between the MAF and the TB. Might as well keep it on the ambient side and not run the risk of damaging it.
Who here actually blows through the MAF??
- Thread starter Super Matty P
- Start date
Super Matty P
Banned
- :
- 2003 Supercharged Protege5
air travels through your piping towards the TB....when you close the TB air hits the flap and backtracks through your plumbing...the very first thing it should see is the BOV. this releases the pressure and keeps it from backing up through your MAF/blower.
on a re-circulated system you want it to be as close to the TB as possible (ater the maf) and you want the re-circulated air to be re-introduced AFTER the MAF to keep it from being re-registered.....a lot of "re's" in that statement.
my supercharger is a different story. The BOV will be IN FRONT of the MAF on the charge side because a belt driven blower is constantly trying to cram air into the TB. the bypass stays open and vents excess pressure out until a vaccuum source senses a load on the engine. At that point the bypass snaps shut and all of the pressurized air is crammed into the engine.
on a re-circulated system you want it to be as close to the TB as possible (ater the maf) and you want the re-circulated air to be re-introduced AFTER the MAF to keep it from being re-registered.....a lot of "re's" in that statement.
my supercharger is a different story. The BOV will be IN FRONT of the MAF on the charge side because a belt driven blower is constantly trying to cram air into the TB. the bypass stays open and vents excess pressure out until a vaccuum source senses a load on the engine. At that point the bypass snaps shut and all of the pressurized air is crammed into the engine.
THEGOLDPRO
Member
lol so which one is it???? my firend and i were a talking bout this yesterday, i said maf before bov, because of the blow back air, he said maf after the bov, so i dunno now, lol
Super Matty P
Banned
- :
- 2003 Supercharged Protege5
i think you are right...on a turbo car I'd want the BOV between the MAF and TB....what are you using to control fuel/timing?? you MAY have problems with increased lag after doing this.
THEGOLDPRO
Member
just a fuel pressure regulator, why would this increse turbo lag?????
Super Matty P
Banned
- :
- 2003 Supercharged Protege5
when you vent to atmosphere the air that is vented has already been metered by the MAF, when the throttlebody re-opens it has to re-spool and re-build pressure. On a recirculated system the discharged air is pumped back into the inlet tract and ready to go decreasing the time it takes to get back in the motor.
this is how I understand it. I may be off.
this is how I understand it. I may be off.
THEGOLDPRO
Member
so were all in aggrement that you want the MAF before te BOV, , as to not have blow back air???? im still in a pissing match with my buddy over this, he says as close to the TB as possible, i say before the BOV.......... any more comment on this, or has any one done this to see how the car works.
Super Matty P said:
either way the BOV venting (to atmosphere, or back into the intake tract) is what allows the turbo to continue to spin at a high velocity, so it builds boost almost instantly when the throttle body opens back up.
recirculating the BOV (or BPV) back into the intake tract only works when the MAF is not in the pressure side. it must be before the tubo. you would return the air to after the MAF, but before the turbo.
hope this helps anyone with Q's in this thread
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Super Matty P
Banned
- :
- 2003 Supercharged Protege5
i'd post a pic of my set-up but the thread would be locked.....unless....
THEGOLDPRO
Member
i just know my car stubbles at idle when i come down from boost, so i figure this is because my MAF is freaking out, and not reading the right air, i see your point of putting it after the bov, because it will read the actual air that will be entering my TB, and if i put it before the BOV most of the air that the computer is accounting for will be discharged by the BOV. does this sound right?
- :
- MP5T / 944
I Blow Through The Mass Air and No Problems... Check It...
THEGOLDPRO
Member
do you get any stalling at idle wen coming down from boost? and how does it run?
- :
- 02 1500 4x4, mp3
i been runnng the same way as brian for a long time. no stalling and runs really good. idles fine and all.
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- MP5T / 944
THEGOLDPRO said:
None, there is about 5 feet of hardpipes between the Mass Air and the BOV...
THEGOLDPRO
Member
yeah i saw that, looks good, my bov is roughly a maybe alittle more from my TB, so im just going to put the MAF in between then TB and the BOV and see what happins.Brian MP5T said:
right now i have it on the intake side of turbo, and it runs good while driving, has some hesitation once and a while, it idles fine, but if i were to rev the engine, and let it come down, it will almost stall out, so hopefully this will help out a bit, we will see.
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- 02 1500 4x4, mp3
6 i have gone up to 10.
