Power Fc ?

[GuestyR33]

Im about to purchace an apexi power fc with hc.

Do i still require the stock air flow meter with this

or can i get rid of it.

thanks for any help

[Downforce]

Guesty, you should post these type questions in the forced induction forum - http://www.skylinesaustralia.com/forums/in...php?showforum=8

You would generally upgrade your AFM with the ECU to gain more tuning resolution...

[R31Nismoid]

you cant just "remove" the AFM.

You need to retain it

[Al]

You CAN just remove the AFM, if you buy a Wolf 3D and eliminate the restriction completely

[teazn_r33]

wat is the best afm to get for the power fc thats my question and y cant the stock one work with it

i heard wolf aint the best to use and thats coming from a fair few tuners

but "cars only as good as the tuner"

ive heard alot of good things bout the power fc???

Edited January 26, 2006 by teazn_r33

[paulr33]

the standard r33 airflow meter is not a restriction. turbochargerd cars only have a restriction after the turbocharger themselves. the stock airflow meter is fine on the apexi powerfc upto 250rwkw. then you can change the z32 300zx airflow meter for more power. the airflow meter setup has many advantages over a map sensor style setup.

the powerfc will come out of the box tuned and ready to go on the stock rb25 setup and components and support simple tuneability to get it running. a map sensor setup is not a good reason to choose a map sensor ecu over an afm setup ecu

wold 3d is map sensor only ecu setup which will lack good cold start and accurate tuning, as the maps become 1 dimensional. ie: once you reach target boost the map only increases based on revs increassing instead of air and revs increasing on airflow meter ecu

[Al]

wold 3d is map sensor only ecu setup which will lack good cold start and accurate tuning, as the maps become 1 dimensional. ie: once you reach target boost the map only increases based on revs increassing instead of air and revs increasing on airflow meter ecu

<{POST_SNAPBACK}>

Sorry Paul, what a load of crap You try to sound as if you know and have worked with a MAP ecu, but i beleive you haven't got any experience with one.

MAP ecu's work on Mass Air Pressure (MAP), so instead of measuring a resistance from a AFM, the ecu measures air by pressure. It is tunable using load, pressure, revs, timming, etc. The running operations at ALL temps (ie:cold start, etc) is comparable to any MAF system, just ask ANT95GTR or myself, or anyone else that has a decent mechanic, who knows the ecu. A tunner that claims to tune everything is hopeless as he would only know the basics of each differant ecu, and wouldn't use all available features to get it right.

I have heard too many stories of 10yr old AFM f**king up and causing issues. If AFM don't cause a restriction why do alot of ppl remove the mesh?. Also a lot of big turbo's have a 4" mouth, reducing the intake pipe to 3" to match the AFM is a restiction within itself.

Please find better sources of info, before you mislead others in the wrong direction.

[paulr33]

ok fair enough, perhaps my understanding of it was a little narrow minded. ok for example in the wolf 3d what maps does it have, and what are the axis for the map, like for the fuel map whats the left axis and top axis?

is there any other signals used to give it correction / adjustments?

i believe the mesh trick is an urban hoo haa myth, and does nothing by removing it. the argument of an 10year old afm dying is purely using 2nd hand items, just buy a new one instead

[Al]

wat is the best afm to get for the power fc thats my question and y cant the stock one work with it

i heard wolf aint the best to use and thats coming from a fair few tuners who don't know how to use the Wolf to it's full potential, so bag it to sell you their prefered ecu to keep your business

but "cars only as good as the tuner"

ive heard alot of good things bout the power fc???

<{POST_SNAPBACK}>

I only would trust 2 w/shops to tune the Wolf, in Melbourne.

-EAS Performance, Airport West

-Rank Rotary, Mentone

Just like i would only trust 1 w/shop to tune a PowerFC

- RacePace, east side not sure exactly where

[Al]

ok fair enough, perhaps my understanding of it was a little narrow minded. ok for example in the wolf 3d what maps does it have, and what are the axis for the map, like for the fuel map whats the left axis and top axis?

is there any other signals used to give it correction / adjustments?

i believe the mesh trick is an urban hoo haa myth, and does nothing by removing it. the argument of an 10year old afm dying is purely using 2nd hand items, just buy a new one instead

<{POST_SNAPBACK}>

In all honesty i really don't know a lot

From my limited knowledge it has:

- Fuel map (x=rpm, y=load) [resolution: x=125rpm, y=16 load points per rpm increment]

- Ignition map (x=rpm, y=load) [resolution: x=125rpm, y=16 load points per rpm increment]

- Air temp compensation

- Battery voltage compensation

- Engine temp compensation

Alot of other things i have seen my mechanic play with, but haven't bothered to take note as i have no intention to play with the ecu myself

[paulr33]

In all honesty i really don't know a lot

From my limited knowledge it has:

- Fuel map (x=rpm, y=load) [resolution: x=125rpm, y=16 load points per rpm increment]

- Ignition map (x=rpm, y=load) [resolution: x=125rpm, y=16 load points per rpm increment]

- Air temp compensation

- Battery voltage compensation

- Engine temp compensation

Alot of other things i have seen my mechanic play with, but haven't bothered to take note as i have no intention to play with the ecu myself

<{POST_SNAPBACK}>

thats cool and makes some sense, no one seems to really be interested in the wolf3d as i can't find a great deal of specs / product info on it. this is the most i've seen so far. my main concern regarding map vs maf is that the load axis is fixed once you reach boost pressure because that value is the same all the way through

you can see per attached pic that the map sensor setup once you reach say your boost controllers target that only revs gives increasing map coordination as the "load" is always the same

thus you loose map points / map resolution

[R31Nismoid]

The running operations at ALL temps (ie:cold start, etc) is comparable to any MAF system, just ask ANT95GTR or myself, or anyone else that has a decent mechanic, who knows the ecu. 

If AFM don't cause a restriction why do alot of ppl remove the mesh?. Also a lot of big turbo's have a 4" mouth, reducing the intake pipe to 3" to match the AFM is a restiction within itself

Not at all trying to have a dig, but how long did it take to get all your cold start tuning done and everything?

I dont think it was a one day affair if i recall correctly (like a PowerFC would be)

Again i use my car as example, with that many stock parts.

GT30, 4" intake... Z32 AFM... no restriction at all if it can rattle off 270rwkw @ 17psi. Then 330/24psi/fuel ITs hardly got air problems. Only issue was ignition and then there was a good 30-40kw more

And thats spot on for most cars with GT30's going by most results.

The inlet on the comp housing to the compressor itself isnt 4" so it matters very little.

Different if we are talking 500kw beasts with huge turbos and massive comp wheels that need the most stupid amount of air. But this is a moderate application like most people

Ah ye, removing the mesh is as paul said, a myth. Mine has mesh.

[paulr33]

i didnt mean for this thread to turn into powerfc vs wolf as theres already threads on that and its pointless but i believe the powerfc is the most suitable for the skyline out of the box ecu and the original poster wanted to remove the airflow meter, theres no advantage to doing so, but certainly disadvantages

[MYSTR33]

power fc -d jetro then u can take off AFM

u cant with normal power fc

[paulr33]

yes however the djetro for gtst does not exist, and there's no advantage for a mild street car to move to a djetro based ecu, but certainly disadvantages in doing so

[psybic]

So does anyone have any better info on why MAP sensor is less accurate than MAF?

I hear it all the time. I have now owned two different cars which I have placed Microtech units in.

Each time, I found better response!

Why would cold start be harder with a MAP sensor?

My first car which had an LT8, actually started first time everytime AFTER getting the LT8, which also made it idle spot on from cold start, before that, with stock ecu, it had major issues and took 5mins to warm up, due to an old and dodgy afm and running way to rich.

Also, if your cooler pipe ever comes off, or anything bad in the induction system, the MAP doesn't care, car just goes back to na mode.

Not like an AFM, which will be very confused with any sort of air leak.

From experience, on two different cars with different engines, both street cars, for everyday use, I am saying there is NOTHING wrong with MAP sensors and the tune has enhanced mid range and response in the car so much the car feels like a different car BOTH times.

[paulr33]

what i said up there cleary shows the difference between map and maf based setups. with the map sensor once target boost is reached the value is fixed and the only increasing axis is revs. much like a v8, once the throttle is nailed it only increased based on revs going up.

whereas with the airflow meter setup the load will always be increasing as more and more air is coming in even when target boost is reached as boost is pressure and air coming in is volume.

volume + pressure are two different things.

maf = measure how much air is coming in and tell ecu

map = measure how much air pressure is and guess how air and tell ecu

also the arguement of piping leaks, i would expect something to behave differently if there was a leak. i dont see who thats a good reason to use a map sensor, you can keep running with a failure / leak in the system. hardly helpful, more like dangerous

[R31Nismoid]

So does anyone have any better info on why MAP sensor is less accurate than MAF?

Search button will answer that, its been a highly debated topic in the past 6 months.

There is ooooodles of information in this section of the two sides.

As for cold start, its not "worse"... its just the PowerFC doesnt need you to waste time (days) to get right.

[psybic]

The clear diagrams have no labels on either axis.

Once you reach target boost, how can you flow more air? The dynamics of the head don't change, so at certain boost and certain rpm, my car always flows the same amount of air.

I didn't even need to have cold start altered on my SR20. Factory base with a 30sec tweek on install was enough to keep my cold start acceptable.

[paulr33]

pressure and volume are two different things. a car tyre with 30psi and a truck tyre at 30psi both have different amouts of air in them, despite same presurre, or boost pressure as you may call it.

the map axis are fairly straight forward, top is revs, left is load for airflow meter and load for map sensor

boost is simply a pressure for the manifold, the load based on the airflow meter is always increasing regardless of boost pressure, that is because there is always more and more air coming into the engine. airflow makes power and not boost.

reaching target boost is simply reaching the "target" pressure and nothing else, youll keep intaking more and more air its just that pressure is fixed to a level by a boost controller, and as a result of that the map sensor will always say "air is the same" even though its not