I'm fealing like a big noob asking this, but I'm really not sure
I'm going to be running the stock SOHC MAF for 7psi, where should I be putting it? On the cold pipe, or on the intake pipe before the turbo? I'm going to be running a recirced BOV more than likely if that changes anything. Let me know if there are other things that play into where it should be placed and i'll be happy to tell ya what you need to know. Thanks.
Ryan
MAF position question...
You can put it before the turbo, or in the cold pipe. It's really up to you. I put mine in the cold pipe, and I run an open atmosphere BOV. It works great for me, but most people put the MAF before the turbo because they're scared of a blow through. There really isn't that much difference. Tha main advantage of a blow through is that it allow you to vent your BOV to the atmosphere.
ziggy682 wrote:You can put it before the turbo, or in the cold pipe. It's really up to you. I put mine in the cold pipe, and I run an open atmosphere BOV. It works great for me, but most people put the MAF before the turbo because they're scared of a blow through. There really isn't that much difference. Tha main advantage of a blow through is that it allow you to vent your BOV to the atmosphere.
can you explain the benefit of wasting to atmosphere?
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Drift Machine
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Structure240sx
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what are you going to be using for a fuel system? if your are going to be tunning with an safc and bigger injectors then you can tune to let the bov vent to the atmosphere even if its after the maf. mine has always been recirculated until last week. i dont have any problems since i have an safc.
if you will be using an fmu and no safc and still want to vent the bov then the blow-thru mafs will work nice. or jsut recirculate it. its really up to you
if you will be using an fmu and no safc and still want to vent the bov then the blow-thru mafs will work nice. or jsut recirculate it. its really up to you
ultimatuc wrote:can you explain the benefit of wasting to atmosphere?
Cause I'm a rice boy, and it sounds cool.
Just kidding about the rice boy thing. I'm actually going to recirculate my BOV to see if my turbo will stay spooled a little better between shifts, but I do love the way an open atmosphere BOV sounds.
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Structure240sx
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my recirculated bov was jsut as loud as my now open bov, go figure.
the safc has a decleration air setting to help tune when the bov opens between shifts. you will be fine jsut running an open bov as long as you get those setting close. search for detail on that.
so basically put the maf where ever you want or where ever is easiest
the safc has a decleration air setting to help tune when the bov opens between shifts. you will be fine jsut running an open bov as long as you get those setting close. search for detail on that.
so basically put the maf where ever you want or where ever is easiest
yeah the whole reason I asked is because I went out and measured the intlet/outlet and the conical filter adapter has a 3" in it is factory 2.5" out, and my whole setup is using 2.5" pipe, so I got worried for half a second, but I was pretty sure you could run it on the intake....so thats whats going to be happening :d
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sil80drifter
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1) I don't know how much spool the recirculation will bring, it's not like the turbo will spin faster just becuise you blow a little air at it from the INTAKE side. The pressure is gone from the intake pipes anyway, and the only thing that will keep a turbo spooling is the exhaust. Not the recirculated air.I think most stock setups are recirculated so that the sound doesn't annoy the "stock" driver of the car. Since most of us aren't "stock", we like the whoosh. some don't.
2) The decel function on the SAFC, if anyone is running it on a KA-T, what setting are you using? My friend has a decel function on his Haltech standalone, and he uses it to dump or not dump fuel when he lets off the gas, on his N/A RX-7. He turns it on just to make flames from exhaust though, not for tuning purposes. I wonder if the SAFC decel function is similar to that. What he can set on his Haltech is the RPM below which the fuel will be dumped when the gas is being let off of, and how much fuel is dumped. So he just set the RPM value to 8k, WOTs it for a little (to get the exhaust nice and hot) and lets off, barely playing with the throttle. Flames trail him for good 30+ seconds at a time all the way down to 2000 RPM. We're wondering when his rear wing will catch on fire. It's fun at night though, in front of unsuspecting cars.
sil80
2) The decel function on the SAFC, if anyone is running it on a KA-T, what setting are you using? My friend has a decel function on his Haltech standalone, and he uses it to dump or not dump fuel when he lets off the gas, on his N/A RX-7. He turns it on just to make flames from exhaust though, not for tuning purposes. I wonder if the SAFC decel function is similar to that. What he can set on his Haltech is the RPM below which the fuel will be dumped when the gas is being let off of, and how much fuel is dumped. So he just set the RPM value to 8k, WOTs it for a little (to get the exhaust nice and hot) and lets off, barely playing with the throttle. Flames trail him for good 30+ seconds at a time all the way down to 2000 RPM. We're wondering when his rear wing will catch on fire. It's fun at night though, in front of unsuspecting cars.
sil80
sil80drifter wrote:1) I don't know how much spool the recirculation will bring, it's not like the turbo will spin faster just becuise you blow a little air at it from the INTAKE side. The pressure is gone from the intake pipes anyway, and the only thing that will keep a turbo spooling is the exhaust. Not the recirculated air.I think most stock setups are recirculated so that the sound doesn't annoy the "stock" driver of the car. Since most of us aren't "stock", we like the whoosh. some don't.
Well in my car is does make a difference. Proven with my SBC's graph function. Juts my .02
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sil80drifter
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sil80drifter wrote:you've tried blowing it off to the air, as compared to recirculating, and then you saw a difference?
sil80
Yep. When recirculating the boost graph looks like this between shifts ‾‾||‾‾ instead of ‾‾|/‾‾ when opened to the atmosphere.
A part from that, I don't have an issue with the BOV being vented to the atmosphere... no bogging between shifts or idle issues (a part from the one I've had for a while). So I can decide if I want it recirculated or opened depending if I want go or show.
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sil80drifter
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MY MAF is before the turbo and a Blitz DD BOV in the cold pipe, so it cause to backfire sometime, however, i want to run a hose from the BOV to my MAF , but the problem is that my MAF is attach to the Air filter directly so I can put the recurclate hose before the MAF , but I could put it After , I was just wondering if that works? I know it sounds werid , but believe it or not, my friend had a 1.8T GTX engine , the STock MAF is before the turbo and the stock recirculate hose RUN after the MAF ? do yo know anything about that?
nismo1003 wrote:MY MAF is before the turbo and a Blitz DD BOV in the cold pipe, so it cause to backfire sometime, however, i want to run a hose from the BOV to my MAF , but the problem is that my MAF is attach to the Air filter directly so I can put the recurclate hose before the MAF , but I could put it After , I was just wondering if that works? I know it sounds werid , but believe it or not, my friend had a 1.8T GTX engine , the STock MAF is before the turbo and the stock recirculate hose RUN after the MAF ? do yo know anything about that?
Dude, the reason your buddies GTX has the stock recirculating hose routed after the MAF is because that's the only way it will work correctly.
Think about it. Air goes through the filter, gets metered by the MAF, through the turbo, through the intercooler, then to the throttle body. If you BOV is after the MAF and it vents to the air, it will run rich, because the MAF has already metered that air. When it gets released into the atmosphere, not as much air gets to the throttle body, so the engine runs rich.
With a recirculating valve, the air gets diverted back in before the turbo, but after the MAF. This keeps the air in the system so the engine doesn't run rich. If you routed the recirculated air back before the MAF, that air would get metered twice. If you did this, your car would actually run lean between shifts. That's bad. You don't want to blow your engine the first time you shift.
Look at the picture above. That's exactly how you should route your recirculating hose.
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sil80drifter
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Actually, if you routed the air to recirculate BEFORE the MAFS, the engine wouldn't run lean between shifts, because the MAFS would account for the "new" air being fed to it, and more fuel would be injected into the engine, so it would run richer than if you route it after the MAF. If the air "gets metered twice" then the fuel is added accordingly. I.E. routing the air back before the MAFS would almost have the same effect as blowing it off to the atmosphere.
sil80
sil80