Power Fc ?

[LBR33]

if you dont want to use your AFM get the powerfc DJetro version as that uses a map sensor

[reflex]

power fc all the way. pual r33 knows his sh** when it comes to power fc and its hard to go by the apexi when it comes to r33's.

[Downforce]

get a motec ecu if you dont want to use an AFM and if you can afford it :lol:

http://www.motec.com/products/ecu/m800.htm

[Al]

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.

<{POST_SNAPBACK}>

Fair comment.

But that was more a tune thing not a ecu problem. How many times did Adz take his car, with PowerFC, to ICE Perfomance (to fix the tune) b4 he decided to go to Racepace?

Each car is differant and needs slight adjustments, everything i suggested to be fixed was done and worked properly.

[Al]

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

<{POST_SNAPBACK}>

Paul, i really don't think your info is accurate. Where are you sourcing it from? Drawing two paintshop pics does not convence me of the differance.

Your above comments make no sense

If you change the size of a tyre of course it is going to have differant volume. Luckly for us, the volume of our engines remains constant, so once "target" pressure has been reached, the amount of air will be constant, whether you are using map or maf.

I've always said PowerFCs are a great ecu, but wolf3D is a great alternative and offers a couple of inbuilt features that the PFC doesn't have.

[paulr33]

Paul, i really don't think your info is accurate.  Where are you sourcing it from?  Drawing two paintshop pics does not convence me of the differance.

Your above comments make no sense

If you change the size of a tyre of course it is going to have differant volume.  Luckly for us, the volume of our engines remains constant, so once "target" pressure has been reached, the amount of air will be constant, whether you are using map or maf.

I've always said PowerFCs are a great ecu, but wolf3D is a great alternative and offers a couple of inbuilt features that the PFC doesn't have.

<{POST_SNAPBACK}>

My concepts of MAP vs MAF have been found found on various forums, documents ive found from google and other debates like this one, a open dicussion on the topic.

Yes you are correct, changing the size of a tyre will increase its volume. However increasing its preesure does not. If you pump the car tyre to 40psi and then 42psi it just means there is more pressure, not necessarily is there is more air present.

I have done up an excel spreadsheet of a map trace I did with my car about 20 minutes ago which uses the standard airflow meter (maxing out). I then did a likely MAP sensor trace below with what I would expect to occur with a similar based car but running a MAP sensor instead. On the MAF trace I have marked the spot where I reached target boost pressure (0.80bar) with a pink colour.

On the MAP diagram from this point onwards the MAP sensor would always return the same value, as pressure never changes from then onwards, however on the MAF trace you can see airflow keeps increase despite my airflow meter being maxed out. I suspect with a Z32 (or Q45) the graph would have more variance as it wouldn't just run along the 5volt axis most of the time.

There still isn't a great deal of detail on the wolf features, what features does the wolf offer that the powerfc doesn't out of curiosity?

[paulr33]

Some reference documents:

http://carcraft.com/techarticles/24549/

http://www.findarticles.com/p/articles/mi_...408/ai_n9453101

http://yarchive.net/car/mass_air_flow.html

it should be also noted that the map sensor will read differently based on your location in accordance with air pressure, ie: idle on a mountain will read differently to idle on a street at normal land level

[paulr33]

rename to .xls and open it in excel

maf_vs_map.txt

[Al]

My concepts of MAP vs MAF have been found found on various forums, documents ive found from google and other debates like this one, a open dicussion on the topic.

Yes you are correct, changing the size of a tyre will increase its volume. However increasing its preesure does not. If you pump the car tyre to 40psi and then 42psi it just means there is more pressure, not necessarily is there is more air present.

I have done up an excel spreadsheet of a map trace I did with my car about 20 minutes ago which uses the standard airflow meter (maxing out). I then did a likely MAP sensor trace below with what I would expect to occur with a similar based car but running a MAP sensor instead. On the MAF trace I have marked the spot where I reached target boost pressure (0.80bar) with a pink colour.

On the MAP diagram from this point onwards the MAP sensor would always return the same value, as pressure never changes from then onwards, however on the MAF trace you can see airflow keeps increase despite my airflow meter being maxed out. I suspect with a Z32 (or Q45) the graph would have more variance as it wouldn't just run along the 5volt axis most of the time.

There still isn't a great deal of detail on the wolf features, what features does the wolf offer that the powerfc doesn't out of curiosity?

<{POST_SNAPBACK}>

You have just wrote that your graph for the MAP is what you would "expect" to happen. Sorry to say i really don't beleive you have the experience to even do this, as a IT technecian is hardly the right qualification. I can not prove how the map works, as i am not qualified. You may have done a bit of work with MAF and PFC, but you haven't touched the MAP, but still try to explain/argue something you don't know anything about.

Your theory about the tyre is still incorrect, if you have more pressure in the same space you MUST have more air present, otherwise what is causing the increase in pressure?

I prefered the wolf as it has PIN security and is able to controll boost using the factory solenoid, no need to purchase other add-ons, etc.

Just a thought: (from someone that really doesn't know)

The MAF sensor senses air going into the turbo, but the air after the turbo is more important, at the set pressure. As the turbo has built up boost the rest of the air is expelled through the wastegate, leaving a CONSTANT volume of air in the intake system. Thus the only variable, that both MAF and MAP sensing ecu's need to use is rpm and load; how fast the engine uses that air.

You have a fixed chamber, with fixed pressure, then surely the air volume must also be fixed at a particular load and rpm.

[paulr33]

You have just wrote that your graph for the MAP is what you would "expect" to happen.  Sorry to say i really don't beleive you have the experience to even do this, as a IT technecian is hardly the right qualification.  I can not prove how the map works, as i am not qualified.  You may have done a bit of work with MAF and PFC, but you haven't touched the MAP, but still try to explain/argue something you don't know anything about. 

Your theory about the tyre is still incorrect, if you have more pressure in the same space you MUST have more air present, otherwise what is causing the increase in pressure? 

I prefered the wolf as it has PIN security and is able to controll boost using the factory solenoid, no need to purchase other add-ons, etc. 

Just a thought: (from someone that really doesn't know)

The MAF sensor senses air going into the turbo, but the air after the turbo is more important, at the set pressure.  As the turbo has built up boost the rest of the air is expelled through the wastegate, leaving a CONSTANT volume of air in the intake system.  Thus the only variable, that both MAF and MAP sensing ecu's need to use is rpm and load; how fast the engine uses that air.

You have a fixed chamber, with fixed pressure, then surely the air volume must also be fixed at a particular load and rpm.

<{POST_SNAPBACK}>

Well that's exactly it, thats all I have is a thoery, until someone correct's me and explains otherwise. It's an open dicussion, there must be other people who have comments on this??

What does the PIN feature allow the user to do ?

The AFM and MAP (in this case) measure air coming into the engine, weather it goes out the exhaust or goes out the wastegate shouldnt matter, in theory? as long as they come in they get used up either way

[USRB25S13]

If I had a choice between MAF or MAP setup I would take MAP.

You are correct when the boost reaches it's pressure the voltage from the MAP reads the same. But the RPM's increase and that's when the injecter duty cly increases to give the motor it's required fuel. The trick is to figure out how much more fuel you need and that depends on your setup.

The MAF measures airflow and caculates the amount of fuel needed. Both systems need tuning with MAP needed a bit more.

I owned a turbo honda (Map based) and now the Nissan's MAF system. The problems I have with the MAF is the motor always goes rich between shifts and light throttle under slight load can cause the car to violently cutoff, Thats from going with 2-3 psi and then the bypass valve opening. The nice thing about the a MAP system is BOV's don't affect them (No anouning stalling). If you look at any aftermarket stand alone they are ALL MAP based (AEM, Motec, Haltech, Electromtive, SDS, Megasquirt, ext) It also saves alot of work when building a setup. you don't have to recirculate or worrie about MAF placement.

Don't get me wrong the PFC is nice for most setups. It's plug + play and easy to tune.

[MattSR]

Al, re the tyre theory - you are totally incorrect. An increase in pressure does not mean that more molecules of air are present.

do a google for boyle's ideal gas law or PV=nRT and you will be enlightened.

[psybic]

If you pump the car tyre to 40psi and then 42psi it just means there is more pressure, not necessarily is there is more air present.

<{POST_SNAPBACK}>

This is where I disagree. I think that you have just pumped more molecules of all elements of the gas you are inserting. There will be more oxygen molecules and it will be able to burn more fuel. Just because the volume hasn't changed doesn't mean there isn't more combustable molecules in there.

[Silver_r33]

OK, lets just set something straight here:

For a constant volume if you want to increase pressure you have to:

A ) add more gas (ie additional molecules); or

B ) increase the temperature.

For a given constant amount of gas (note that i said AMOUNT, not volume):

A ) to increase pressure, you reduce volume or increase temperature

B ) to maintain a constant pressure in a reducing volume you have to add more gas or increase temperature.

As MattSR said - PV=nRT, where P is pressure, V is Volume, T is Temperature, n is the amount of the gas in moles and R is a constant.

Does this clear it up?

Edited January 30, 2006 by Silver_r33

[rob82]

Hmmm the old speed density vs MAP debate. Airflow meter based ecu's are the most consistent and efficient means of determining how much fuel is to be injected bar none. Not even fords 32bit floating point PCM is able to match the consisency of holdens, nissans, subaru's mitsubishi, porche, ferrari MAF based systems. That said I believe for went back to speed density due to the numerous amount of MAF's that were failing in the eariler model v8's and this is something that all manufacturers have to deal with. Downside to speed density systems - cam timing. The way the ford PCM works(which I think is the best) is to apply a linear equation (flow on y and manifold pressure on x) for each cam phase angle for every 500 rpm. This requires alot of processing speed and is highly complex.

Speed density based computers do have their advantages on the big horse power race cars over a MAF based ECU as eventually MAF's do cause a restriction and this can occur at lower power numbers then what most think.

[Al]

Your theory about the tyre is still incorrect, if you have more pressure in the same space you MUST have more air present, otherwise what is causing the increase in pressure? 

<{POST_SNAPBACK}>

Notice how i DID NOT SAY increase volume , as volume is a defined constant space, but you need to increase the amount of gas to increase pressure, as we are assuming air temp is also constant.

Thanks Silver_r33

Paul MAF measures air b4 the turbo and MAP measures Pressure after the turbo.

PIN=Personal Identification Number When ENABLED (you can disable at will), ecu will not fire injectors without the number being entered first.

For factory fitted cars, of course MAF is better because if it wasn't all manufactures would be using MAP sensor ecu's. But these cars have multiple millions of research dollars pumped into the tunning. When we buy an aftermarket ecu, this all goes out the window, and the ecu tune is only as good as the tunner. All i am saying is that a MAP aftermarket ecu can be tunned as good as a MAF aftermarket ecu, just depends on the knowledge and experience of the tunner. I just get pissed off when ppl just reguritate the BS that has been feed to them by mechanics who only know how to tune one type of ecu.

I choose MAP mainly because my mechanic knows how to tune the Wolf and i had/have no intension of changing mechanics/tunners as i prefer all mods to be inhouse, therefor only one person is responsible. My car (when tune is finalised) starts up great, idles great, has great response and power, equal to any other car with the same mods.

Paul if you really are serious about getting info on MAP ecu's or in particular on Wolf3D, why not just ring Steve at AEM, the manufacturer of the wolf ecu.

[Al]

Al, re the tyre theory - you are totally incorrect. An increase in pressure does not mean that more molecules of air are present.

do a google for boyle's ideal gas law or PV=nRT and you will be enlightened.

<{POST_SNAPBACK}>

Are you sure?

I don't think so

You have a gas cylinder, constant temp., how do you increase the pressure?

[benl1981]

Far out. Think about it - when you increase the pressure in your tyre from 40 - 42psi what are you putting in there?? Heat or Air???

Sure you could raise the pressure by heating the tyre (that's why there is difference between cold and hot pressure readings) but when you go to the servo they have air compressors. You are adding air to the tyre.

Pv = nRT has been exploited here. You could use the ideal gas law before and after the turbo on the compressor side.

P1V1/R1T1 = P2V2/R2T2

Before ............ After compression

As you increase pressure from the turbo compression (i.e. P1 to P2) you have to increase Temp (T1 to T2) also to maintain the ideal gas law. As R1 =R2 (ideal gas constant). Your actual volume flow rate should be about the same before and after. On the inlet you will be sucking air under negative gauge pressure hwen you are boosting

Edited January 30, 2006 by benl1981

[bLaQ.bOi]

f**k im so nooob... trying my hardest to learn...

but wtf is a power fc... wat does the FC stand for? wats ASM?

[paulr33]

f**k im so nooob... trying my hardest to learn...

but wtf is a power fc... wat does the FC stand for? wats ASM?

<{POST_SNAPBACK}>

all the answers you seek are here:

http://members.dodo.com.au/paul/docs/power...powerfc-faq.htm