Whizbang

ive seen this done and i know the car will run but my question is how different does the MAF act? could i compensate for any oddities with proper tuning (emanage). i know several people have done this and i would like to hear input from either them or the more educated FC owners.

joeylyrech

iTrader: (11)

my brother have this setup on his S4 TII and work great hes running
a s5 turbo 2 maf after the turbo(tb side),you can control the maf with the e-mange its easy just setup the rotary dials to B,8,9 thats the setup for the regular s4 maf,then go in to the maf settings on the support tool and choose the newer s5 version then the e-manage would change the flow meter mapping and the car will run fine then you can tune from there,he did some timing tunning cause the flow meter map affect the timing but the car pulls really hard.iff you keep the s4 flow meter dont run over 10psi because whe blew up 2 off them at 10psi and thats wy he changed to the s5,overall if you place the flow meter on the intake side the car will respond faster thats my experience i know that people will disagree about this but that how the cars feels.

eddierotary

iTrader: (7)

S5 AFM is the way to go because the S4 one blows up the top of it. i read from somebody that did it on the forum that works and it gives you a better respond but it leans the car up so if you planning to doit you need a apexi Safc or any aftermarket fuel controller so you can adjust the fuel on it. implanning to do mine but im waitin to do a different TB elbow to doit. search around and you should find writeup about it

slpin

iTrader: (9)

the afm is designed to meter air at atmosphere pressure, so a bar...
when you run it after the turbo, say... .4 bar, it is assuming a volumne of air has a bar of pressure, while in reality, that volumn of air has 1.4bar of pressure.

which would make your car run lean, as the flapper/cone isnt opening as much.

but... it could also, inturn, 'meter' more air.

airworks-fc3s

sounds reasonable! i've tried that once on my s5...

put the afm after the turbo, idling and cruisin' was ok, but when under boost the engine began to stall.. totally wrong measuring i suppose!

Whizbang

could i get a NA S5 one? the emanage says it will use ANY same type maf sensor from any car (as long as its the same style.) so i could use a 968 one if i wanted to spend money. and i can get the S5 one for cheap to free.

slpin

iTrader: (9)

e manage can use any maf sensor, but your ECU cant use any maf sensor.

eddierotary

iTrader: (7)

that why you need a Safc to rich it out

C. Ludwig

iTrader: (27)

Here's the fundamental problem with moving the air flow sensor to the other side of the turbo. The Mazda sensor is not a mass air flow sensor. It is an air velocity sensor. What's the difference and why do we care?

Mass air flow sensors do just that. They directly measure the mass of air that moves through the meter. There is no interpolation of the mass. It's directly measured. The ECU looks at that mass number and computes the exact mass of fuel needed to produce the appropriate a/f ratio. Viola!

The air velocity meter, either S4 or S5, do not directly measure the air mass. They measure velocity of the air. They also take a temp reading of the air as it passes through the air meter. Ever wonder why there are two air temp sensors? By looking at the air velocity and the air temp the ECU can compute the air mass.

So why do we care? What happens when air is compressed? It gets heated. If the outlet temp from the compressor was constant and the air velocity sensor was calibrated for that always considerably greater than ambient temp (whether it's pre or post intercooler) there would be no problem putting the sensor there. Problem is the outlet air temp varies radically and the sensor isn't calibrated for it. The sensor sees a high temp and it assumes there's less air mass than there really is.

Whizbang

but all i really care about is the emanage getting a signal from the maf. but the correction maps are going to be based off a boost sensor instead of the maf sensor.

mind you this is all temporary seeing i have all the parts floating around until i get a grand for a standalone

C. Ludwig

iTrader: (27)

What I'm trying to tell you is that the sensor isn't giving you a signal that is totally relavent to what is going on as far as air flow. So it's next to impossible to build a compensation map. You're going to change to a standalone later anyway? Leave the sensor where it's supposed to be.

Whizbang

fine! ill do it the easy way. lol.


l

slpin

iTrader: (9)

the temperature is not as important as the fact that the air is compressed..... but you forgot to mention that!

anewconvert

iTrader: (1)

OK, seriously. You need to be SURE you are using the correct term.


The RX7 does NOT come stock with a MAF. It comes with an AFM which is a COMPLETELY different animal. If you are planning on running a MAF, like a GM/ford hotwire Mass Air Flow sensor then you can put it damn near anywhere you want as long as you tellt he computer what to expect as far as temps are concerned.

As for an Airflow Meter, the AFM, it operates COMPLETELY different from a MAF and as such evidently needs to be placed before the turbo unless you are telling the computer otherwise.


You are confusing the snot out of me, and if Im confused Im sure there are others confused. So which is it, an S4/5 AFM or an aftermarket MAF sensor?

BC

walken

iTrader: (6)

Forgive my ignorance, but it my head it only seems having the AFM after the turbo it would read full open all the time? The vacuum of the engine should be strong enough at the TB to keep it open all the time. Then under boost it would also push it fully open. So the car would think it was under full load all the time, then freak out when it checks the TPS signal. Your timing would be all over the place.

slpin

iTrader: (9)

the afm has a spring in it.

because it is after the turbo, it doesnt make any difference when the turbo isnt generating boost because it is still before the throttle body, and at atmosphere pressure

when the turbo spins, more air is going thru, so it opens more, but it is pressurized air, so it isnt open as much as it should.

Nosferatu

I wouldn't think it would be a problem running the AFM "post" turbo with the e-manage.The e-manage has 16x16 correction maps for fuel/ignition so I can't see why you couldn't tune out the AFM position difference with a piggyback that has more load points then some stand alones.As was mentioned above, If the AFM is under-reading on the pressure side of the turbo then your ignition will be more advanced since the primary stock ignition map is based on rpm/load(AFM).You may want to consider the ignition correction a little closer.

classicauto

iTrader: (3)

Sorry, I stopped reading the thread after this post.

I tried rigging up my full TO4-S, FMIC, bla bla bla on the stock ECU with an e-manage, had to relocate the AFM, do a bunch of other garbage to even make the car run HALF ***. No fun at all. Not to mention I could NEVER get the E-Manage to control ignition (I bought all the harnesses, it just didn't work) and the timing was the major issue that needs addressing with full upgrades.

Im currently installing the Haltech and a rebuilt 1/2 BP'd motor........and undoing 90% of the **** I wasted my time on before.

Unless you need to drive this car for some reason to get around - wait and do it right - you'll be spinning your wheels...which is fun IN the car, but not ON the car.

C. Ludwig

iTrader: (27)

The voice of reason has spoken.

Nosferatu

Other people have blue emanage's working correctly with ignition on FC3S's.I guess if you can't get a piggyback running,you are on a uphill battle with a standalone.

NZConvertible

While it's thrue the air temp will be higher, it doesn't matter because with this mod you need you use an interceptor to essentially recalibrate the AFM signal to give the mixtures desired. If you tune it right, you get the right mixtures. According to the FSM the AFM's air temp sensor can read to at least 185degF, which is much higher than would be expected post-FMIC.

Firstly, there is no vacuum before the throttle. Secondly, the AFM measures airflow, not pressure. You're getting the two confused but they are completely different animals.

On a side note, this mod doesn't suffer the inherent risk normally associated with AFM interceptors on FC Turbos; that is negative fuel corrections to compensate for larger injectors causing advanced ignition timing that increases the risk of detonation. In this case you will always need to use positive corrections even if you tune for leaner-than-stock mixtures.

classicauto

iTrader: (3)

Where? I could only get the leading to operate...I tried splitting the signal to both trailing coils but it wouldn't run it - if you can do it, by all means come and show me or tell me how or point me to a write up.

Not to mention that to tune the primaries (had the secondaries wired as additionals so I could use the full 16x16 map instead of modding the airflow signal) I had to bump the airflow signal....and according to my timing light it was at full advance at 2000rpm!!!!! (on leading, as I said, couldn't ever get the trailings operational on the unit)

The Haltech is butter compared to hacking the E-manage in...