blow through type mafs?

[daniel240]

im going to convert my pull through type hacked mafs into a blow through type. the main reason is because my car keeps stalling when i shift to neutral or push in the clutch, and im going to see if this fixes it, because right now my mafs is pretty close to the turbo inlet and i dont have room to move it farther away. i have a few questions before i do this. 1.) for the hacked mafs you need a certain ID pipe for it to work,(im using a 2.7'' ID) so would all the IC piping need to be greater than or = to this ID? right now i have 2.5'' piping from the turbo to the IC and 3'' from the IC to the TB. i wouldn't think it would matter but i want to make sure. i was planning on putting the mafs in the cold pipe, before the TB. and putting my bov on the hotpipe, right after the turbo. does this sound ok before i go cutting and welding it up? anyone w/ this setup, please let me know how it worked out. i have heard a few people w/ blow through types having problems w/ throttle response. thanks.

[:: orion ::]

I ran my 2.75" ID hacked MAF as a blow through and got 10.9:1 A/Fs...b/c the rest of the pipe was only 2.25".

Think, if a "tunnel" of air that is being forced through the piping is 2.5", then bumps to 2.7" for a 4" long section, then back to 2.5"...I'd bet it has a tendency to stay at around 2.5" like the rest of the piping. That's the reason I'd bet mine saw 10.9:1 as a blow though, and +13:1 as a draw through.

So unless your could side pipe is all 2.7"...

- Brian

[daniel240]

yea, thats one thing i was wondering about, although, i have 3'' from the ic to TB. i was going to put the mafs pretty close to the TB so there would probably be a good 2 ft of 3'' piping before my mafs. do you think that would be ok then? thanks

[:: orion ::]

That sounds like the way to do it...make the MAF the smallest part of the cold pipe, it should read properly.

- Brian

[daniel240]

ok thanks ill try it out and see how it works. i will still have 2.5'' piping from the turbo to the ic but i dont think that will matter.

[MikeMurphy]

your TPS is working properly, right?

[daniel240]

your TPS is working properly, right?

i dont know, why? and how would i check?

[cyrus240sx]

dont you get that whole stalling problem if your bov is venting to atmosphere?.... you are rerouting it correct?

[daniel240]

dont you get that whole stalling problem if your bov is venting to atmosphere?.... you are rerouting it correct?

yes im rerouting it. and i understand that it would stall if i vented it to the atmoshpere, that is why im going to try a blow through type.

[daniel240]

also, would it be ok if i have my bov right before the mafs, approx. 8'' before? or would that mess up the mafs readings?

[daniel240]

heres a pic of where im going to put the mafs. would this be too close to the bov located on the other side of the red coupling? i dont really want to have to cut it off and reweld it somewere else if i dont have to.

[andrave]

why not put it as far over as possible? that way its downstream from any fluctuations the bov might induce, away from the bends up stream, etc. besides if you are of the throttle body school of bov mounting then that places it closer to the throttle body (note that is doesn't really matter).

[MikeMurphy]

i dont know, why? and how would i check?

I think you can get the feedback through the OBD port. I would take a quick look! Pretty much any shop should have something for this. Im not sure if the nissan CONSULT is universal, but OBD is. Should be producing an a CEL if its not working, but stranger things have happened.

Obviously I dont know for sure, but if you havent checked it, it would be a good idea.

and hey, if its faulty you can always sell it on ebay (hahaha, sorry, couldnt help it )

anyways, moving on...

[daniel240]

why not put it as far over as possible? that way its downstream from any fluctuations the bov might induce, away from the bends up stream, etc. besides if you are of the throttle body school of bov mounting then that places it closer to the throttle body (note that is doesn't really matter).

well, that would be the simplest place to put it, where i have it in the drawing. i would only need to cut the end off that big pipe, and would only need one extra coupling and clamp.