TUrbo PR5's, S-AFC
- Thread starter mikem
- Start date
I think that some points are being missed here.aftershock63 said:
The O2 is only affective in closed loop. It becomes null and void once in boost for the most part. It is Ideal to have both sensors controlled so that your transition is smooth and your curves are within spec forpower . Not dumping fuel to correct an issue.
Now, One of the reasons I havent come out with the AFCII yet is this. The timing advance becomes HORRENDOUS when f- ing with the MAF signal. There are ways around this. I am making arrangements to help with this issue very soon. I just need a little more time. We will bring two options in two weeks. If anyone has any questions as to how the AFC affects timing I will be more than happy to explain.
aftershock63
Member
- :
- 2004 G35 Sedan 6mt
Yes yes please explain because I've been very interested in making the msd programable dis-2 work I think if you combined the 2 you would have basically a good standalone
DooMer_MP3
Member
Yeah, what do you mean the timing advance "becomes" horrible? Does the ECU advance timing when you f' with the fuel?
Chris
Chris
OK
If anyone has not tuned into our thread on engine management, then I will go over some points here. I'll be back later with a link to the thread that was started by twighlight protege on "engine management".
NOTE: I will make this a s simple as I can. So any of you advanced gurus out there already know what I'm talking about.
Your fuel map- Consists of load and speed sites. Picture a cross word puzzle. But this one looks like a square box. 16x16. 256 sites. The map will be scaled depending on the vehicle application. Meaning your x or y axis, depending on the ecu and software, will be for load and speed. (maf,tps and rpm) for example your y axis will be scaled like this.
500rpm
1000
1500
2000
etc until all 16 sites on that row are filled.
The load sites will go in this order.
NA aplication here-
-14.7
-12
-10
-8
and so on signifying atmospheric load conditions. Depending on throttle position and load.
FI vehicles will have half the NA resolution because they have to take into account the load and speed site that additional VE (volumetric efficiency ) will come in with a turbo.
Now for example-
AT 3000 rpm, closed loop and 25 % throttle you will be in load site (b) (example only guys)
The more throttle you give it the more load the MAF will show to the ecu. the site will go up to lets say (c). But as your airflow and throttle position increase eventually your rpm will catch up right? So you end up in site (d)
Depending the site you are at the ECU will determine based on load and rpm the proper duty cycle for the injectors and ignition lead. The less the throttle the more the timing. The more the throttle the less the timing lead you need. Cylinder filling is always going to be more efficient as you are allowing atmospheric pressure thru the manifold and into the cylinder.
So with these base maps the ECU fuels and ignite the combustion chamber.
Along with these maps there are "sub" maps. Correction values used for air temp , throttle accel, decel fuel, a s*** load we wont get into here. In closed loop the ecu will use these maps and the O2 to fine tune the emmisions output of the motor.
So with the example I gave above you will exactly how this affects the timing and fuel curves.
If at the same 3000rpms, and 25% throttle you manipulate the MAF this is what happens.
If you are going to ask for less fuel. (the case with larger injectors)
You want to take away MAF voltage that the ECU sees. That way it will add less fuel. Your load site changes. It will correspond with rpm but you are sending false parameters to the ecu to correct a rich condition at idle. The load site will be lower.
The ecu sees that the load site you are SUPPOSED to be in is not met. You now accelarate. You are still taking away voltage from the ECU. So as not to flood the engine upon throttle. Instead of going to the load site it is supposed to see actually you decrease the load value the ECU sees and it will add the timing it was supposed to give at a lower throttle range. Remember the less the load the more the timing lead. So the more you manipulate the MAF signal to get it to fuel correctly the lower the load site you are showing the ecu. You are in a stage of advanced ignition lead. BUT your boost pressure and cylinder filling was for a completely different site. The site you are supposed to be in has a retarded ignition value. So for that example, in actualty you would have gotten about 19 degrees of advance. By lowering the load site the ECU sees you are corresponding it to read off a lower value. Depending on how low you are going with the voltage and the way the scaling is internally to the ECU you may be getting 25-30 (again example). But this is what I mean by affecting timing.
Now you have those that will ADD voltage to the MAF for more fuel. Thats fine. It will work in open loop. Because in cloased loop the O2 feedback will overide it. Now you get into an area with the protege that the ECU will in most cases not give you enough timing. But what we have found with the protege injectors in open loop is that there isnt enough fuel for too much boost preesure.
Yeah the car runs rich from the factory. You have some room to take away fuel, BUT it directly affects timing lead again. The more boost pressure the more airflow the timing lead you ADD by leaning out the mixture.
With larger injectors and open loop you are trying to correctly add fuel in boost. BUT you have no idea what site you are in with the ECU. You may get lucky and never lean it out enough to have a problem. Now all you have to do is make sure that the stock ECU doesnt learn what you are doing
There is alot more to it. I tried to be as lamen as possible. The point is to stop FIGHTING the ECU. Work with it or just get some fuel and ignition management that will have its own complete control over all parameters
Cough Cough Like the stuff we are working on and will be marketing soon. Cough Cough
Just let me know what else I can explain. If I didnt get too clear please search for the thread called "engine management" I have alot of info I relayed there.
If anyone has not tuned into our thread on engine management, then I will go over some points here. I'll be back later with a link to the thread that was started by twighlight protege on "engine management".
NOTE: I will make this a s simple as I can. So any of you advanced gurus out there already know what I'm talking about.
Your fuel map- Consists of load and speed sites. Picture a cross word puzzle. But this one looks like a square box. 16x16. 256 sites. The map will be scaled depending on the vehicle application. Meaning your x or y axis, depending on the ecu and software, will be for load and speed. (maf,tps and rpm) for example your y axis will be scaled like this.
500rpm
1000
1500
2000
etc until all 16 sites on that row are filled.
The load sites will go in this order.
NA aplication here-
-14.7
-12
-10
-8
and so on signifying atmospheric load conditions. Depending on throttle position and load.
FI vehicles will have half the NA resolution because they have to take into account the load and speed site that additional VE (volumetric efficiency ) will come in with a turbo.
Now for example-
AT 3000 rpm, closed loop and 25 % throttle you will be in load site (b) (example only guys)
The more throttle you give it the more load the MAF will show to the ecu. the site will go up to lets say (c). But as your airflow and throttle position increase eventually your rpm will catch up right? So you end up in site (d)
Depending the site you are at the ECU will determine based on load and rpm the proper duty cycle for the injectors and ignition lead. The less the throttle the more the timing. The more the throttle the less the timing lead you need. Cylinder filling is always going to be more efficient as you are allowing atmospheric pressure thru the manifold and into the cylinder.
So with these base maps the ECU fuels and ignite the combustion chamber.
Along with these maps there are "sub" maps. Correction values used for air temp , throttle accel, decel fuel, a s*** load we wont get into here. In closed loop the ecu will use these maps and the O2 to fine tune the emmisions output of the motor.
So with the example I gave above you will exactly how this affects the timing and fuel curves.
If at the same 3000rpms, and 25% throttle you manipulate the MAF this is what happens.
If you are going to ask for less fuel. (the case with larger injectors)
You want to take away MAF voltage that the ECU sees. That way it will add less fuel. Your load site changes. It will correspond with rpm but you are sending false parameters to the ecu to correct a rich condition at idle. The load site will be lower.
The ecu sees that the load site you are SUPPOSED to be in is not met. You now accelarate. You are still taking away voltage from the ECU. So as not to flood the engine upon throttle. Instead of going to the load site it is supposed to see actually you decrease the load value the ECU sees and it will add the timing it was supposed to give at a lower throttle range. Remember the less the load the more the timing lead. So the more you manipulate the MAF signal to get it to fuel correctly the lower the load site you are showing the ecu. You are in a stage of advanced ignition lead. BUT your boost pressure and cylinder filling was for a completely different site. The site you are supposed to be in has a retarded ignition value. So for that example, in actualty you would have gotten about 19 degrees of advance. By lowering the load site the ECU sees you are corresponding it to read off a lower value. Depending on how low you are going with the voltage and the way the scaling is internally to the ECU you may be getting 25-30 (again example). But this is what I mean by affecting timing.
Now you have those that will ADD voltage to the MAF for more fuel. Thats fine. It will work in open loop. Because in cloased loop the O2 feedback will overide it. Now you get into an area with the protege that the ECU will in most cases not give you enough timing. But what we have found with the protege injectors in open loop is that there isnt enough fuel for too much boost preesure.
Yeah the car runs rich from the factory. You have some room to take away fuel, BUT it directly affects timing lead again. The more boost pressure the more airflow the timing lead you ADD by leaning out the mixture.
With larger injectors and open loop you are trying to correctly add fuel in boost. BUT you have no idea what site you are in with the ECU. You may get lucky and never lean it out enough to have a problem. Now all you have to do is make sure that the stock ECU doesnt learn what you are doing
There is alot more to it. I tried to be as lamen as possible. The point is to stop FIGHTING the ECU. Work with it or just get some fuel and ignition management that will have its own complete control over all parameters
Cough Cough Like the stuff we are working on and will be marketing soon. Cough Cough
Just let me know what else I can explain. If I didnt get too clear please search for the thread called "engine management" I have alot of info I relayed there.
DooMer_MP3
Member
Well there you have it. Another excellent explanation, and my knowledge increases again. Thanks perf.
Chris
Chris
lol....this thread is alive again...
Mikem ....where is that wiring diagram? and the pictures?
I still don't believe this....
Mikem ....where is that wiring diagram? and the pictures?
I still don't believe this....
DooMer_MP3
Member
I don't think they're working on getting the SAFCs to work with the protege anymore. They've moved onto the AEM PnP unit in the other thread.
Chris
Chris
Revived from the dead.
Yes we are NOT bringing this product out. We tested and tested but with the limiting capabilties of this unit. We saw that it would actually hurt the vehicle more than help. IF you are dead set on trying it PM me and I will give you contact info so that I can go over it with you in person if you like.
To sum it up the AFCII is only able to see 0-5 volt input references. The stock MAF siganl is not a linear 0-5 volt reference. Also it did a number on the detonation characteristics associated with manipulating the MAF/pressure signal to the stock ECU.
I DO NOT IN ANY WAY RECOMMEND ANY PIGGYBACKS FOR THIS ECU. AT FIRST WE THOUGHT IT WOULD BE GREAT TO BRING ANOTHER OPTION TO THE FORUM, BUT IT HAS DEVISTATING EFFECTS ON PERFORMANCE AND RELIABILITY.
Instead we decided to test and market the best all around EMS solution on the market today; The AEM PnP system.
Yes we are NOT bringing this product out. We tested and tested but with the limiting capabilties of this unit. We saw that it would actually hurt the vehicle more than help. IF you are dead set on trying it PM me and I will give you contact info so that I can go over it with you in person if you like.
To sum it up the AFCII is only able to see 0-5 volt input references. The stock MAF siganl is not a linear 0-5 volt reference. Also it did a number on the detonation characteristics associated with manipulating the MAF/pressure signal to the stock ECU.
I DO NOT IN ANY WAY RECOMMEND ANY PIGGYBACKS FOR THIS ECU. AT FIRST WE THOUGHT IT WOULD BE GREAT TO BRING ANOTHER OPTION TO THE FORUM, BUT IT HAS DEVISTATING EFFECTS ON PERFORMANCE AND RELIABILITY.
Instead we decided to test and market the best all around EMS solution on the market today; The AEM PnP system.
I liked these days when we were helping and teaching this community. BUT in recent times "some" people find it to be a doggy dog world and think that by bashing people and utterly lying about their personality it makes for a more beleivable atmosphere. I miss the old daysDooMer_MP3 said:
Perf...those days are far and few between.... but..the OGs of the board...don't give up...
MP3skaterNC
JDM *****.
- :
- slotege mp3
Would there be anyway to say run the safc off a map sensor, instead of the maf or tps, that way you could add fuel in on boost situations only?
Yes there is. Here are some of the problems with this.MP3skaterNC said:
Your car is boosted. you would require a min of a two bar map sensor. The map sensors' voltage gain in proportion to the airflow/pressure in the manifold will never be the required amount needed by the stock ecu.
For example:
stock MAF voltage with Key on - 1.6-1.8v
1 bar map with key on - approx 1 v depending on manufacturer
2 bar map with key on - approx .48v depending on manufacturer
You need to be at a min of 1.6 or the car wont even start. Then some people think that by installing larger injectors that the ecu will still send a voltage to ground the injectors. That is false. Unless you get a linear voltage measurement to the ecu across the entire rpm, load and throttle range it wont work. That is where our module came in. It worked to get the vehicle running and adjustability was there. BUT you could only adjust so much before you out of parameters and the CEL would come on.
We have found that the majority of the proplems on the protege ECUs are very conservative and generic ignition and fuel maps in open loop. They rely soley on the O2 sensor to get you stoich under partial throttle and low rpm. They never did a good job on the transtional mapping between open and closed loop. Once the car hits a predetermined rpm and closed loop kicks in they run 10:1 A/F ratios along with very aggressive timing values for the VE of this particular car.
So it was a project we didnt think was going to help in setting a standard for our work. It is very limited and the stock mapping (excuse the french) SUCKS.
There are better ways to do things and get your car running better with the most performance reliably.
Little Beavis
Member
- :
- 2001 MP3-T (#911)
First I'll say. . .I'm not familiar with that unit, but why can't you use a MAP sensor for additional injectors (or can you)? I was thinking that was what Jamie was asking. Is that possible? I realize you'd have a *hiccup* when you went into boost and would still need a voltage clamp, but could you do this?
OK first in order to even READ pressure (above atmospheric) you would need a 2 bar map min. That was my point above. It wouldn't be linear in any way to run the vehicle at all. After all that is all the AFC can do. It is not an extra injector controller. My understanding was that jaime wanted to know if the car would run with the MAP not the MAF.Little Beavis said:
Now to use a map to control extra injectors in ANY setup is the only real way to go anyway. Pressure measurement from the MAP should be used as the reference for calculated load and airflow for the given setup.
Little Beavis
Member
- :
- 2001 MP3-T (#911)
Thanks, we agree then. I just interpretted it differently, I knew you would need a 2 bar map (or even a 3 bar), but I just thought he was trying to control additional injectors (guess I read too much into that one).perfworks said:
