Open atmosphere BOV and maf on coldpipe

[RedlineRacer]

I know alot of people have trouble with their bovs being open atmosphere. I remember reading somewhere that if you put the maf on the coldpipe, you can have it do open atmosphere. Is that true? I got a friend who is almost finished with his SR, and he wants in to be open atmosphere. How far away does the maf have to be from the throttle body? Isn't it like 18 inches?

[sr240mike]

Its whats called a blow throught setup. You should put about 8" of straight pipe before and after the maf to get an accurate reading. Bends immediately before and after the maf causes distortion which can mess up the reading. Then you can vent the bov to atmosphere since the maf is only reading the air thats getting to the engine.

[Mr. Spool]

from what I have read you can have bends after it, but at least 8in before the throttle body. I am about to go to my garage and make mine blow through right now.

[RedlineRacer]

having no bends would be pretty tough. You have such a sharp angle you that you have to make in order to get from the TB to the intercooler if you have a front mount.

[Mr. Spool]

Dont have a front mount, i have a customized side mount. I just fabed up the pipes and put it on, it runs alot smoother at Idle, however I was not able to hear the bov working, I hope its not shot.

[sr240mike]

A bend immediately behind the maf will cause an unstable reading. Maybe at least 4-5 inches behind it would be enough.

[tastyratz]

this interests me id love to run open bov instead and that seems to be a not so bad idea. anyone successfully pull this off yet? just make sure to put the ait right next to it as well if you have one so the readings dont get distorted... another thing would be like the new 00+ celicas how they have fins inside that direct the airflow to be more laminar over the maf sensor...

consider this thread subscibed...

[Mr. Spool]

I just did it last night, My car idles better and pulls harder than before, not drastically harder but better none the less

[RedlineRacer]

lets see some pics

[sr240mike]

The only thing I would be worried about with a blow through setup is oil getting on the mass air filament from venting the crankcase to the intake tube and oil getting past the turbo seals. Throttle response should be way better since the maf is so much closer to the throttle valve.

[Mr. Spool]

I have trouble with a dirty maf before, due to the cold air intake that I had on my turbo set up, but all you have to do is spray it down with some contact cleaner.

[tastyratz]

yea but you can run a decent catch can setup as well... ventilation tube location doesnt matter either right? if you want you could just put it closer to the intake manifold couldnt you?