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Old 12-02-2008, 07:07 PM   #1
schrott
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Default h6 maf on 2.2l

yeah, i tryed it.....

yeah it works.....

now i really need a good intake.

same plug.

big difference in size.

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Old 12-02-2008, 08:13 PM   #2
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how are you making it fit the 2.2l intake manifold? adapter? And what about the ECU MAF scaling? does the sensor compensate the MAFv/grams of air or does the ECU determine it? Since its plug and play, id bet its the latter. If so, this is probably a very bad idea on stock ECU calibrations.
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Old 12-02-2008, 08:55 PM   #3
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why is this a bad idea ? why wouldn't i want to mate this up to a good intake, and let more air into the engine ?

i just swapped the air box (after trying different box configurations from some spairs) it plugs into the same air hose. was planning on an intake for a 2.5

what is the 'ecu maf scaling' ?

i can turn a mean wrench, but your speaking a different language.
i disconnected the battery, plugged it in, re-connected the batt, and presto ! she fires right up !

in my head it makes sense......
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Old 12-02-2008, 09:42 PM   #4
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well the ECU has a calibration for the MAF voltage. Basically it correlates a given MAF voltage with a specific volume of air. The MAF voltage scaling that is programmed into the ECU will be how it figures out this value. So when your old setup was at wide open throttle and at 3200 rpm it would have a given amount of air passing through the MAF sensor and into the engine. Your ECU with the correct scaling for the MAF sensor, would calculate the mass of air going into the engine and calculate the amount of fuel needed to acheive the proper Air Fuel Ratio (AFR). Now when you are at WOT and 3200 rpm, you will have more air passing through and into the engine but the MAF sensor will tell the ECU the same voltage, and the ECU will think its the same amount as before because the ECU doesnt know the MAF is bigger, it just knows what the MAF voltage is (the MAF voltage varies based on how much air is passing over the wire, more air passing will cause the voltage to rise, and less air = lower voltage) So it will then call for the incorrect amount of fuel and you will have a lean air fuel ratio. too lean for too long and POP goes the motor.

Depending on how your ECU controls knock, it may pull timing and help lessen the damage, but i doubt it will be enough. and even if it does pull timing and get the knock to stop, you performance gains will actually be losses because so much timing has been pulled. this is just a theory, i dont have any idea how your ECU works but its probably something like this. and it may not even recognize the lean condition via knock, it might be totally under the ECU "radar" if you will. I could even see it misfiring due to pre-ignition, burned valves/pistons, etc.

I respect a good wrench-turner. I turn wrenches for a living. Hope this helps and doesn't confuse you. Im not the best technical writer in the world.
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Old 12-03-2008, 08:17 PM   #5
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Raceface, you might be overlooking that the bigger MAF is using a sensor calibrated for the larger volume. It should give the same output for a given amount of air intake. The only thing that will change is the physical flow limit and possibly the velocity of air going through the intake system as a whole.

I don't see this as anything that would add power specifically, but it shouldn't hurt anything.

Jay
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Old 12-03-2008, 09:26 PM   #6
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Quote:
Originally Posted by Storm View Post
Raceface, you might be overlooking that the bigger MAF is using a sensor calibrated for the larger volume. It should give the same output for a given amount of air intake. The only thing that will change is the physical flow limit and possibly the velocity of air going through the intake system as a whole.

I don't see this as anything that would add power specifically, but it shouldn't hurt anything.

Jay
So are you saying that the MAFv for the new MAF is going to be equal as in 3v=2.0g/s on the 2.2MAF and 3.0v=2g/s on the h6 maf? That would be the only situation that would make it so that you could swap MAF's without any change in fueling. But, if the sensong elements themselfs are the same, how does it compensate for the MAF section I.D. being larger without having unique MAFv scaling? I have overanalyzed things b4, but i still dont see how this will work properly. AND on its own, the problem of MAF scaling as a whole is still a legitimate concern. When changing intake, even just the shape/length/track a MAF rescale is necessary on MAF based ECU systems. I changed my Ej253 intake pre TB but retained the stock MAF sensor and still had AFL trends that were way off and required a rescale. My wideband verified my AFR's having changed. Id hate to have the OP use this H6 MAF with almost no gains and be running outside of the normal/safe AFR's.
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Old 12-03-2008, 09:49 PM   #7
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not that it matters, but the MAF is from the 3.3 h6.

i was thinking that if i hook up a decent intake tube to the bigger MAF then it could let in more air to mix.

i am running a legacy engine with the dual outlet heads, headers, cat back. i was thinking that i should let the engine breath more air in to match how much air i can let out.

is there a way to 'reset' the ecu so it knows to breath more ?

oh, and Raceface, im not trying to talk any s#!^. i read through these pages like the bible. i love learning new things, and thank you for sharing what you have learned !

i take it i should remove the h6's MAF hugh ?
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Old 12-03-2008, 10:42 PM   #8
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schrott - i didnt think you were trying to talk and **** at all. Its nice to see someone with a new idea (H6 MAF) I'm just not sure how well it would work in the whole scheme of things.
It's also worth mentioning that N/A engines rely more on velocity of intake/exhaust to acheive better cylinder charging than a forced induction system and an intake that is too large may affect the intake velocity. But the actual intake manifold is staying the same after the TB so this may be a non-concern. just thinking out loud. I am by no means an expert on this topic. I am learning, like you. I have been learning for a couple years now and these are the concerns that I have.

I hope that more data/facts can be brought up by other members to bring you to a better conclusion about how the H6 MAF will change the way your engine works. There is at least one more member that i think will have the ability to add some useful information to this discussion. Hopefully he will come across this thread and post a reply.

I, personally, would remove it until i understood what exactly was going on with it. I wish you had a WideBand O2 Sensor or DBW ECU so we could plug into RomRaider and test this thing out. But that is not the case.
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Old 12-03-2008, 11:25 PM   #9
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1) due to the differing sizes of the MAF housings, it's almost certain that the MAF scaling for each of those setups will be entirely different. Since you can't reflash your ECU to change your MAF scaling, you're almost certainly going to have screwed things up badly. Possibly even badly enough to blow the engine.

2) The stock MAF housing is not a flow limitation that an NA car will ever see. Until you see 300hp at the wheels, a 3" tube can flow more air than you'll ever use. Don't sweat it.
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Old 12-04-2008, 07:24 AM   #10
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That's pretty much what I'm thinking. Although as I think more and more about it, the overall range should be wider on an H6 simply because it will injest more air than an H4. With a wider range of volume using the same range of sensor voltages, it would make sense that for a given amount of air (in g/sec) the two MAFs would show a different sensor value. The whole scaling thing is kinda new to me as well, so we're all learning here. Willaty shed some light on it too, but if it were me, I'd try it and check the A/F ratios to be sure.......

Jay
Quote:
Originally Posted by RaceFaceXC View Post
So are you saying that the MAFv for the new MAF is going to be equal as in 3v=2.0g/s on the 2.2MAF and 3.0v=2g/s on the h6 maf? That would be the only situation that would make it so that you could swap MAF's without any change in fueling. But, if the sensong elements themselfs are the same, how does it compensate for the MAF section I.D. being larger without having unique MAFv scaling? I have overanalyzed things b4, but i still dont see how this will work properly. AND on its own, the problem of MAF scaling as a whole is still a legitimate concern. When changing intake, even just the shape/length/track a MAF rescale is necessary on MAF based ECU systems. I changed my Ej253 intake pre TB but retained the stock MAF sensor and still had AFL trends that were way off and required a rescale. My wideband verified my AFR's having changed. Id hate to have the OP use this H6 MAF with almost no gains and be running outside of the normal/safe AFR's.
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Old 12-04-2008, 08:01 AM   #11
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Someone need to test this with the flowbentch. If i'm thinking rigt h6 maf would need more flow to show the same voltage as 2.2 maf. It's like this: engine is sucking the same amount of air on both but the air on the bigger maf is moving slover thus showing smaller v.
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Old 12-04-2008, 08:17 PM   #12
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^^^ That is what i was thinking also. That bigger maf is made to flow more air, so if you put it on a engine that isnt flowing as much, and the maf scaling is more for the larger maf, you would end up richening the mix. That's what I was thinking at least. The only way to be sure would be to wideband it with the stock sensor, then reset the ecu and try the larger maf, and wideband that.

But an hour or so of dyno time might be cheaper than buying a wideband just for this test. I would really like to know the outcome of this, maybe another upgrade for us slow N/A guys.


~Josh~
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Old 12-04-2008, 09:13 PM   #13
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Originally Posted by ballitch View Post
That bigger maf is made to flow more air, so if you put it on a engine that isnt flowing as much, and the maf scaling is more for the larger maf, you would end up richening the mix.
No, exactly backwards. Presuming that both the H4 and H6 sensors NOT housings, use the same element, the sensor in the H6 housing will return a lower voltage for a given flow volume. If you don't correct the MAF scaling, this will cause the ECU to underestimate the amount of air entering the engine, and therefore under-fuel the engine, causing it to run lean which is bad.

Quote:
The only way to be sure would be to wideband it with the stock sensor, then reset the ecu and try the larger maf, and wideband that.
OK, first of all, you're making no sense at all because you can't "wideband it with the stock sensor", whatever the heck you think that means. What would actually happen is that the AF Learning and AF Correction would peg in an attempt to get the engine to run properly. This would cause the car to throw a P0171 CEL and run very lean at WOT. It would also take away the ECU's ability to protect the engine if you have a mechanical or fuel issue that legitimately causes the engine to run lean.

Quote:
But an hour or so of dyno time might be cheaper than buying a wideband just for this test.
Not around here it wouldn't be. An hour of dyno time is about 2x as much as a WBO2.

Quote:
I would really like to know the outcome of this, maybe another upgrade for us slow N/A guys.
Jesus. This would in no way be an upgrade due to the fact that the stock MAF housing isn't a friggen problem.
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Old 12-04-2008, 09:45 PM   #14
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do we know that the H6 (or any engine that flows more air) still uses a similar max MAFv for the flow that engine will see. the more i think about it, the more i think that the range will be larger for sometyhing that flows more air. Do the turbo's have a similar MAFv range or do they go to a higher voltage than the n/a setup when they exceed the mass flow that the n/a is capable of? I.e. do the n/a's peak @ say 4v and the turbos peak @ 6v? or do they both peak at the same Voltage? Either way, a rescale is extremely necessary.

Last edited by RaceFaceXC; 12-04-2008 at 10:14 PM.
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Old 12-04-2008, 10:12 PM   #15
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When He said "wideband it with the stock sensor" i think he meant to test AFR's with a wideband with the stock MAF sensor. ???
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Old 12-04-2008, 10:32 PM   #16
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Quote:
Originally Posted by RaceFaceXC View Post
do we know that the H6 (or any engine that flows more air) still uses a similar max MAFv for the flow that engine will see. the more i think about it, the more i think that the range will be larger for sometyhing that flows more air. Do the turbo's have a similar MAFv range or do they go to a higher voltage than the n/a setup when they exceed the mass flow that the n/a is capable of? I.e. do the n/a's peak @ say 4v and the turbos peak @ 6v? or do they both peak at the same Voltage? Either way, a rescale is extremely necessary.
I know the turbo cars actually have almost identical scaling to ours. I'm willing to bet it's the same physical sensor element for them as for us. Look at your stock scaling, it goes up to 300g/sec. The top end of the map is just wasted resolution to us.
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Old 12-05-2008, 08:31 AM   #17
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i dont really understand what 'scaling' is... ?

the inside of the h6 MAF (the element ?) is the same as the stock one. looks to be, anyway.

is there a way to 'talk' to my stock ecu, and let it know what to do ?

when i put in the bigger MAF, i disconnected my battery to 'reset' the ecu. is that part right ?

i did something like this to my old Z31. bigger TB from an s13, shorter intake, and bigger MAF. turned that thing into a sliding machine.

im just trying to get something out of this engine while i put together a little something with my h6 engine.

thank you guys, for getting into this, and talking things through. its one thing to read someones post, its another to ask questions pertaining to my own car.

thank you, keep it comming !
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Old 12-05-2008, 08:33 AM   #18
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oh yeah, so am i wrong in thinking that since i have headers and exhaust that breath out better, i should put something in to let her breath in better ?
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Old 12-05-2008, 12:13 PM   #19
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Ah..thanks for this post. I have a 2.2ltr '97 Outback Sport that has been sitting in my garage for months with nothing to do. My borla header has a leak so I just let it sit. Now this is enlightning.

Really good info. Never knew this would fit. I did a dyno test of three different ECUs.
http://forums.nasioc.com/forums/show...highlight=dyno

Which stock 2.2ltr ECU do you have? Part# AD61A or Part# AD400? I run AD400 and the car ran richer than I'd like it too. The larger maf with a larger diametered intake (that matches the maf sensor diameter) may be the ticket.

I tried fitting this to my old Subaru XT6 without luck.
http://subaruxt.com/forum/viewtopic.php?f=1&t=1862
Some useful info may be in there.

Kinda excited now. I think I have an SVX Maf in my garage from that old test. Will have to check it out sometime this weekend.


An BTW: I would not recommend ANYONE do this without consulting a professional. ***Disclaimer***

I am no professional. If you do attempt to do this, at least put premium fuel into your fuel tank before testing. Test on a dyno, use an EGT gauge if one is installed or at least use an air/fuel ratio meter. That's all for now!

Last edited by Kevin Thomas; 12-05-2008 at 12:23 PM.
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Old 12-05-2008, 02:10 PM   #20
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Quote:
Originally Posted by schrott View Post
i dont really understand what 'scaling' is... ?
Scaling is the set of numbers that tells the ECU how to convert the voltage from the MAF sensor into the amount of air passing the MAF sensor.

Quote:
is there a way to 'talk' to my stock ecu, and let it know what to do ?
No, your ECU is too old to reprogram.



Look, there's no way to make this setup work on your car. It just can't be done. And there's absolutely no benefit to the H6 MAF housing for you. Just quit screwing around and put the stock MAF housing back before you blow your engine.
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Old 12-05-2008, 07:15 PM   #21
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Originally Posted by williaty View Post


Look, there's no way to make this setup work on your car. It just can't be done.

Not true at all.

If you install a Perfect Power (PP6), it will work fine as now you can "tune" the MAF signal in the right direction.

I run larger MAFs on two of my 1990 vehicles.
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Old 12-05-2008, 07:27 PM   #22
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Yeah, it seems that unless you have a highly modified engine that will need the increased MAF diameter (being choked my the smaller MAF), a larger MAF wont provide any gains due to reducing restriction in the intake track. AND, it will make for a few problems that MUST be ironed out before any additional power can be made. The biggest of these is:

rescaling the MAF. Which s necessary even if the MAF sensor elements and signal to air mass ratio is identical between the two MAF's, because it will change the properties of the intake which requires a rescale to be accurate.

Having a highly modified engine AND an ECU that can be reprogrammed would be a different story.

To answer you inquery about having headers and no aftermarket intake and wondering if the headers are useless:

No. The headers are going to improve the engines flow somewhat. Less than with an intake also, but it will still be an improvement. But without the ability to retune the ECU (i.e. adj timing, AFR's) then the actual power gains from just slapping on headers, HFC, catback, etc etc will be minimal.
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Old 12-05-2008, 10:11 PM   #23
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so... i looked at the pp6, i should say looked for the pp6. i also read some review about it. good and bad.

without telling me to look in another thread: what can i use for my ecu that isnt too expensive ? now keep in mind that i dont plan on running this engine forever, but i do need a little power for now.

i know, speed costs money.... blah blah blah... i know... thats why i dont want to sink more cash into my po-dunk 2.2, when i have a 3.3 sitting in the car tent waiting for the daddy bad touch.

so... put the 2.2 MAF (its the .....31) back in and put an intake on. still dont get how letting in more air will blow up my engine.... i thought that the throttle body, intake manifold, then valves, would take care of distributing the air.

i love this place !!

bring in on guys !!!! i want info, oppinions, rants, and your own experiments.

kevin.... i like the way you think brother ! i have five ecu's sitting around out of different impreza's.

could i use the h6's ecu...... hmmm...
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Old 12-05-2008, 10:59 PM   #24
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Originally Posted by schrott View Post
still dont get how letting in more air will blow up my engine.... i thought that the throttle body, intake manifold, then valves, would take care of distributing the air.
...


The ecu gets a signal from the MAF, if the maf says x amount of air, it gives y amount of fuel. but if you put a larger maf in and it says x amount of air but actually flows 2x amount of air, but only injects y amount of fuel, you run lean and POW, run lean and detonate.

Not much cheaper than the PP6 is around.
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Old 12-06-2008, 12:17 AM   #25
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Originally Posted by schrott View Post
so... i looked at the pp6, i should say looked for the pp6. i also read some review about it. good and bad.

without telling me to look in another thread: what can i use for my ecu that isnt too expensive ? now keep in mind that i dont plan on running this engine forever, but i do need a little power for now.

i know, speed costs money.... blah blah blah... i know... thats why i dont want to sink more cash into my po-dunk 2.2, when i have a 3.3 sitting in the car tent waiting for the daddy bad touch.

so... put the 2.2 MAF (its the .....31) back in and put an intake on. still dont get how letting in more air will blow up my engine.... i thought that the throttle body, intake manifold, then valves, would take care of distributing the air.

i love this place !!

bring in on guys !!!! i want info, oppinions, rants, and your own experiments.

kevin.... i like the way you think brother ! i have five ecu's sitting around out of different impreza's.

could i use the h6's ecu...... hmmm...
distributing the air isnt the problem, its the measuring the air thats the problem. ALL Electronic Fuel Injection (EFI) vehicles use some sort of sensor (MAF, MAP, etc) to measure the mass of the air being drawn into the engine. The MAF measures the mass of the air based on how much voltage is necesary to keep a "thermistor" wire at a steady temperature. more air will cause more cooling and therfore require more voltage to keep it "hot". That is a simplified explination, but here is the whole idea. http://www.egr.msu.edu/autoweb/Class...ns/maflow1.pdf

So your MAF measures air that way and then tells the ECU the voltage. Your ECU recieves the voltage signal from the MAF and says "based on the voltage, this is how much air is coming in, so ill inject X amount of fuel to achieve an AFR of Y". So if your ECU is getting data that tricks it into thinking more or less air is coming into the engine than actually is (X), it will inject too much or too little fuel and cause a rich or lean condition (relative to what "Y" should be). A rich condition is bad but probably wont cause any type of engine failure unless its chronic and is causing cylinder wash or something. It will reduce power and kill your miliage, though. But a lean condition can cause hot spots in the combustion chamber (valve margins, spark plug electrodes, etc), flame front speed being too high and cylinder pressures peaking before TDC, high cylinder temps. All of these are hard on the engine internals and can lead to failure of things like bearings, valves, burning the piston (donuts for pistons is a bad thing), etc.

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