http://cgi.ebay.com/ebaymotors/AFC-FUEL-MIXTURE-ADJUSTER-CHEVY-COBALT-SS-SATURN-ION_W0QQcmdZViewItemQQcategoryZ33741QQitemZ8012439 858QQrdZ1

Also look on the following web site, the manufacturer of the Mini AFC 2.2 (go on the support section, install instruction, engine electronics, afc 2.2).

http://www.easyperformance.com/

I talk to the seller, and they will probably have some test results (done on a Cobalt SS with a 2.8 pulley) within a week or so. EvilcobaltSS (on this very forum) is the man who is testing the unit on his SS/SC. Hoping he will give us some results soon ...

Since I don't know if the stock injectors are already at their maximum flow at WOT with a smaller supercharger pulley, I cannot be sure if the Mini AFC will get the job done. Even with the PSI-FI kit, I have whitnessed some lean condition at WOT on a Cobalt SS with a wideband sensor.

That has got to be the most expenisve bottle of snake oil i've seen in a long time

What do you mean by snake oil ?

he means it probly dont work worth shit. just like those 10 dollar performance chips that are just a 10 cent resistor and all the do is turn on your ses light

This very device has been previously proven to work on other GM cars like Grand Prix GTP ...

I guarantee it works. I have had it on my car. Its as plug and play as you can get.

Hijacking the MAF signals sounds like a really bad idea. If you need that much customization you're probably better off with something like megasquirt. I can see people trying to use this to mask lean/rich codes. The ecu handles your fuel/air mixture. If it doesn't work right, fix it, don't slap duct tape over it.

Its a MAF signal amplifier... the idea is simple... the computer thinks its getting more air, it adds more fuel... honestly there is no reason why it wouldn't work... unless are ECU (which seem pretty fucking smart to me) realize there is something wrong... so I'm waiting to hear about that guys car before I make any judgments....

LOL at HeppyCat. Theres just a liiiiiittle bit of difference between megasquirt and an AFC :rolleyes:
I guess you could go tell the GTP guys that the AFC is a bad idea and doesnt work, Im sure they would loooove to hear that :rolleyes:

I have that exact AFC, and its great. Probably the best mod I have for my car. It really is that easy to use too. I would buy it for your car with out hesitating.

Not saying that this product doesn't work, but aren't people having problems with CAI making the computer seeing too much air, and making the car too rich? If that is the case, are people going to use this to control the amount of air down so that it runs leaner than stock, making it an ideal A/F ratio?

http://cgi.ebay.com/ebaymotors/AFC-FUEL-MIXTURE-ADJUSTER-CHEVY-COBALT-SS-SATURN-ION_W0QQcmdZViewItemQQcategoryZ33741QQitemZ8012439 858QQrdZ1

Also look on the following web site, the manufacturer of the Mini AFC 2.2 (go on the support section, install instruction, engine electronics, afc 2.2).

http://www.easyperformance.com/

I talk to the seller, and they will probably have some test results (done on a Cobalt SS with a 2.8 pulley) within a week or so. EvilcobaltSS (on this very forum) is the man who is testing the unit on his SS/SC. Hoping he will give us some results soon ...

Since I don't know if the stock injectors are already at their maximum flow at WOT with a smaller supercharger pulley, I cannot be sure if the Mini AFC will get the job done. Even with the PSI-FI kit, I have whitnessed some lean condition at WOT on a Cobalt SS with a wideband sensor.


Still doing dyno testing but went to SEMA for a week so it slowed me down. Needless to say soon as I have proven data that I believe is valid I will share it. It really doesn't matter becasue everyone seems to have there own opinion on what works and what doesn't I guess everyone has a dynojet in thier backyard and wideband commander on thier cars :D

i used to have an afc for my grand prix also and it works great. however you're really just tricking your car's pcm and if the afc is not adjusted correctly you may run out of maf causing you to run lean. i ended up getting tuner software (sorta like hp tuners or mega squirt) and adjusted the injector flow rate table which gave me much better results but for what it is the afc is a good product!

A megasquirt is a build it yourself EFI controller. There is a world of difference between a megasquirt and a AFC. The effort to build and setup a megasquirt is quite a task.

Price has been dropped from 180 to 160 $ on E-Bay.

A megasquirt is a build it yourself EFI controller. There is a world of difference between a megasquirt and a AFC. The effort to build and setup a megasquirt is quite a task.

my apologies i assumed megasquirt was some sort of tuner software. now that i know yes that would be quite different.

Isn't the issue in the long term PCM activities not the short term? The PCM is looking for certain events to happen and it's looking for desired readings. In other words it would work for awhile and then go into limp mode after weeks or whatever. The PCM is alot smarter than the GTP and GEN III pre 02 PCMs where MAF translators are right at home. I experienced this long term issue on the Cobalt, it will run fine for a week or so then BAM it's on the side of the road waiting for me to come with the laptop to clear the code(s). Not saying it doesn't work, it's just that this PCM is super duper smart.

I don't see why this won't work. Your just telling the PCM that its getting more air than it really is, so it richens up the mix. I can't see any way for the PCM to override it or revert back to make the controller useless. Unless your just maxing out the injectors/MAF.

Your only modifying the sensor, not trying to splice the PCM (piggyback) which I feel would have a better chance of the PCM fighting it than just an AFC. The PCM won't argue with the sensor though.

But I'm pretty sure its almost fullproof.

We will see it very soon ... :o)

I don't see why this won't work. Your just telling the PCM that its getting more air than it really is, so it richens up the mix. I can't see any way for the PCM to override it or revert back to make the controller useless. Unless your just maxing out the injectors/MAF.

Your only modifying the sensor, not trying to splice the PCM (piggyback) which I feel would have a better chance of the PCM fighting it than just an AFC. The PCM won't argue with the sensor though.

But I'm pretty sure its almost fullproof.What makes the LSJ PCM calibration so different than your GTP is the presence of a significant number of rationality DTCs. There is no such thing as a P0068 or a P1182 (and a great many others) in the L67 calibration.

So where you guys can use a MAF signal conditioner to trick your PCM, the LSJ PCM would observe the MAF value as being in error because it doesnt "jive" with the observed throttle opening, IAT, MAP and RPM. What's worse as the DTC doesnt identify WHICH parameter is not in agreement with the others, that's to be determined by the diagnostic process and a TECH2.

So I'm not saying there isnt some potential in this device, just that you wont be able to compare sucess as "apples to apples" against what's been proven sucessful with the L67 crowd.

WopOnTour

What makes the LSJ PCM calibration so different than your GTP is the presence of a significant number of rationality DTCs. There is no such thing as a P0068 or a P1182 (and a great many others) in the L67 calibration.

So where you guys can use a MAF signal conditioner to trick your PCM, the LSJ PCM would observe the MAF value as being in error because it doesnt "jive" with the observed throttle opening, IAT, MAP and RPM. What's worse as the GTC doesnt identify WHICH parameter is not in agreement with the others, that's to be determined by the diagnostic process and a TECH2.

So I'm not saying there isnt some potential in this device, just that you wont be able to compare sucess as "apples to apples" against what's been proven sucessful with the L67 crowd.

WopOnTourThat's what I was trying to say. Thanks again WOT, you're always right there with the good info! It's not the same PCM.

Good point. I guess we'll never know till someone tries it...

I was thinking also about a MAP clamp, what do you think guys ?

I was thinking also about a MAP clamp, what do you think guys ?
heh no, been there done that......dont even bother.

heh no, been there done that......dont even bother.

What did it do? What didn't it do?

Could you answer here please Clownhair ?

Just take his word for it, it didn't work out. Clown is reputable. He's got some good info, just like WOT, DanM and the like. Face it guys and gals, this car's PCM is touchy.

What did it do? What didn't it do?
The computer wouldn't read any boost with the clamp on (verified by a scan tool) and would lean out very badly.

Didn't you clamp way too low at 1.8V ?

Didn't you clamp way too low at 1.8V ?
We hooked an external air pressure up to the map and at 12 psi it read 1.8 volts.

So you got a 5v current enters the map and with 12 psi the current was 1.8v ?

We hooked an external air pressure up to the map and at 12 psi it read 1.8 volts.


Hmm I have my DTEC hooked into the MAP sensor to use it as a load metric. I definetly get past 4 volt when I am at full boast. I get like 5 volts at 14.5 psi.

Hey I think clownhair got a little tuning error ? I'm pretty damn sure that clamping it at 1.8 v is waaaaaay too low and will make the car run lean as hell !

Hmm I have my DTEC hooked into the MAP sensor to use it as a load metric. I definetly get past 4 volt when I am at full boast. I get like 5 volts at 14.5 psi.
:confused: we used a volt meter right on the map sensor, this was done by zzperformance not me. We also hooked the voltmeter up and ran a wire into the car and even at 17 psi we only were getting around 2.2 or so volts.

OK think I'll make some testing too, thank you clownhair.

Maybe you were on the temperature wire, not the pressure one ?

Maybe you were on the temperature wire, not the pressure one ?
I can go look tonight and see which wire it was, I am at work right now.

Hmm I have my DTEC hooked into the MAP sensor to use it as a load metric. I definetly get past 4 volt when I am at full boast. I get like 5 volts at 14.5 psi.

OK thanks ! I think that clamp it at 4.7 v should help, very interesting, thanks guys (clownhair too) :o)

Also the MAP sensor is a 5V one, it's much more realistic to see 5V at WOT (at 14.5 PSI) than kinda 2V.

Clownhair what happened ?

The best way to figure out what scale a map sensor is, take the voltage reading of the sensor when the car is on and the engine is off. This voltage is 0 or atmosphere. Granted baro changes and altitude is going to affect this reading but it is close enough.

Example If you take the reading and the sensor reads 5v then you have a 1bar map sensor. If the reading is 2.5v then it is a 2bar sensor.

OK thanks ! I think that clamp it at 4.7 v should help, very interesting, thanks guys (clownhair too) :o)

Also the MAP sensor is a 5V one, it's much more realistic to see 5V at WOT (at 14.5 PSI) than kinda 2V.

Clownhair what happened ?
what happened with what?

its a greyish blue wire we tapped btw.

What happened with the fact that you clamp it so low if it's a 5V sensor ?

What happened with the fact that you clamp it so low if it's a 5V sensor ?
I took it off. I didnt last 10 minutes on my car

Hijacking the MAF signals sounds like a really bad idea. If you need that much customization you're probably better off with something like megasquirt. I can see people trying to use this to mask lean/rich codes. The ecu handles your fuel/air mixture. If it doesn't work right, fix it, don't slap duct tape over it.


IM WITH HIM dont send ur computer false readings ur computer is making it work for your car it knows how to make ur car run at its best performance with its stock parts do lie to it.. ur only going to brake things n ur engine

Yesterday, we've done one full hour of dyno tuning, and as expected the Mini AFC 2.2 works ! It allowed to fine tune the air fuel curve, even if the stock injectors haven't a lot of room to play with them. Even without any tuning from the Mini AFC 2.2, the stock PCM still seems to keep the air fuel ratio not higher than 12.5 at WOT.

I didn't receive my bigger injectors in time for the dyno tuning session. So we doesn't measure any fuel pressure or neither the stock injectors flow. About the bigger injectors, maybe I will need them only with an even smaller pulley than 3".

Here are my current setup as tested yesterday :

2,5" catback
3" pulley @ 15.2 PSI
SCdyne Header
Denso Iridium #IK20 Spark Plugs (gap 0,035")
K&N high flow filter #RU-2710 with lower lid removed

We also get the Aeroforce Interceptor gauge installed, but unfortunatly the cable they sent me caused an interface conflict with my SS PCM. So we haven't been able to get the gauge work properly, neither measure the Injector Pulse width for the stock injectors.

Results: We consistently went to 222 WHP and 192 WTQ; giving 265 SAE BHP and 230 TQ.

My previous setup (with CAI, but without Iridium Plugs and without Mini AFC 2.2) was roughly 212 WHP and 185 WTQ.

When we compare the current setup to my stock dyno runs of 190 WHP and 170 WTQ, that's a 17 % increase in HP and 13 % increase in torque.

Have a nice day !

Yesterday, we've done one full hour of dyno tuning, and as expected the Mini AFC 2.2 works ! It allowed to fine tune the air fuel curve, even if the stock injectors haven't a lot of room to play with them. Even without any tuning from the Mini AFC 2.2, the stock PCM still seems to keep the air fuel ratio not higher than 12.5 at WOT.

I didn't receive my bigger injectors in time for the dyno tuning session. So we doesn't measure any fuel pressure or neither the stock injectors flow. About the bigger injectors, maybe I will need them only with an even smaller pulley than 3".

Here are my current setup as tested yesterday :

2,5" catback
3" pulley @ 15.2 PSI
SCdyne Header
Denso Iridium #IK20 Spark Plugs (gap 0,035")
K&N high flow filter #RU-2710 with lower lid removed

We also get the Aeroforce Interceptor gauge installed, but unfortunatly the cable they sent me caused an interface conflict with my SS PCM. So we haven't been able to get the gauge work properly, neither measure the Injector Pulse width for the stock injectors.

Results: We consistently went to 222 WHP and 192 WTQ; giving 265 SAE BHP and 230 TQ.

My previous setup (with CAI, but without Iridium Plugs and without Mini AFC 2.2) was roughly 212 WHP and 185 WTQ.

When we compare the current setup to my stock dyno runs of 190 WHP and 170 WTQ, that's a 17 % increase in HP and 13 % increase in torque.

Have a nice day !



What took you so long :D Shoot me a PM I have few other ideas that are in the works. I am getting up there in the power these days. I think 300RWHP is not far away. Good results on your car. Sooner or later when you start to make bigger power you Will need a clutch. After about 250FWHP mine started slipping on hard accel. Got the Spec 2 now and she runs fine and the alm. flywheel made a few HP to boot.

Forgot to say that the precise Mustang dyno we used reads roughly 10 to 12 % lower than an optimistic Dynojet ! Yes my clutch is already slipping too.

jmc007, just wondering, but what is the aeroforce tech interceptor gauge doing exactly? I have one on my GTP and it originally had a conflict with the 00-01 GTP PCM's, but Todd over at Aeroforce Tech worked on it and found that if the power is ran through the fusebox, it works fine (something about the PCM saw the extra draw in power as the car being stolen)...and what size are the stock injectors btw?

Unfortunately the installation of my Aeroforce gauge isn't finished yet; I will receive another cable from Aeroforce this week.

I asumne that the stock injector flow is 42 lb/hr at 60 PSI, but I never get one measured.

wow, you guys are maxing out 42lb (42.5 maybe?) injectors with just a 3" pulley/intake/exhaust setup? That sounds crazy, but then maybe the difference is the 4cyl vs 6cyl in the gtp? The gtp's are able to drop to a 3" pulley with stock injectors (lotta supporting mods needed, stock pulley is 3.8"), but the stock injectors are only 36#...so is the difference in the different # of cylinders? jmc007, good luck with that aeroforce gauge, you'll LOVE it when you get it working, its worth the wait! :)

edit - what size is the stock pulley, anyone?

wow, you guys are maxing out 42lb (42.5 maybe?) injectors with just a 3" pulley/intake/exhaust setup? That sounds crazy, but then maybe the difference is the 4cyl vs 6cyl in the gtp? The gtp's are able to drop to a 3" pulley with stock injectors (lotta supporting mods needed, stock pulley is 3.8"), but the stock injectors are only 36#...so is the difference in the different # of cylinders? jmc007, good luck with that aeroforce gauge, you'll LOVE it when you get it working, its worth the wait! :)

edit - what size is the stock pulley, anyone?

3.34 i think??

I missed most of this discussion, but I have some info that may be helpful to know about the mini-afc if it hasn't been said already.

Sooo, In the PCM calculations are made to determine spark advance and fueling. At WOT, the computer uses the MAF signal, and the MAP signal to determine the weight of the air/volume. As it sees more air come in, it adds more gas, it's that simple. So if your MAF is normally reading at WOT 10000hz at x rpm, you take a mini-afc and fool the computer to think it's 11000hz, and yes, she'll squirt more gas. However, the PCM is seeing that extra volume of air come in. It takes the MAF reading, cross refences the MAP, and now that extra air must mean there's a ton of extra pressure in the Cyl...which there isn't. The PCM doesn't know this, so it backs of ign advance a lot. I had a mini-afc for several years until I realized the limitation there.

So you go smaller on the pulley, go lean, add a mini-afc, it pulls timing: You took a parasitic power adder and made it more parasitic, went to a fatter fuel curve, and lost free hp due to reduced timing. You may gain some from the smaller pulley, but not as much as doing it a different way.

The only real effective way to tune these cars is with a flash pcm device. Otherwise you're loosing efficient ways to make more power.

wow, you guys are maxing out 42lb (42.5 maybe?) injectors with just a 3" pulley/intake/exhaust setup? That sounds crazy, but then maybe the difference is the 4cyl vs 6cyl in the gtp? The gtp's are able to drop to a 3" pulley with stock injectors (lotta supporting mods needed, stock pulley is 3.8"), but the stock injectors are only 36#...so is the difference in the different # of cylinders? jmc007, good luck with that aeroforce gauge, you'll LOVE it when you get it working, its worth the wait! :)

edit - what size is the stock pulley, anyone?


A stock Cobalt SS is making as many WHP than a supercharged GTP, but with only 4 cylinders (4 injectors) instead of the 6 one in the GTP. So the SS ones must be bigger or the fuel pressure ran is higher.

3.34 i think??

Yes it is.

I missed most of this discussion, but I have some info that may be helpful to know about the mini-afc if it hasn't been said already.

Sooo, In the PCM calculations are made to determine spark advance and fueling. At WOT, the computer uses the MAF signal, and the MAP signal to determine the weight of the air/volume. As it sees more air come in, it adds more gas, it's that simple. So if your MAF is normally reading at WOT 10000hz at x rpm, you take a mini-afc and fool the computer to think it's 11000hz, and yes, she'll squirt more gas. However, the PCM is seeing that extra volume of air come in. It takes the MAF reading, cross refences the MAP, and now that extra air must mean there's a ton of extra pressure in the Cyl...which there isn't. The PCM doesn't know this, so it backs of ign advance a lot. I had a mini-afc for several years until I realized the limitation there.

So you go smaller on the pulley, go lean, add a mini-afc, it pulls timing: You took a parasitic power adder and made it more parasitic, went to a fatter fuel curve, and lost free hp due to reduced timing. You may gain some from the smaller pulley, but not as much as doing it a different way.

The only real effective way to tune these cars is with a flash pcm device. Otherwise you're loosing efficient ways to make more power.

That's why I got 2 MAP clamp to fine tune it along with bigger injectors. Please be patient we will all see the results together ...

Don't forget too that the Cobalt SS intercooler is an air to water design which is VERY efficient, in fact that's amazing !

Cobalt SS intercooler

wait, cobalt ss intercooler, is that stock, or aftermarket? if aftermarket, is there a link to this??

That is stock !

oooh i didn't realize they had stock intercoolers on them, maybe thats how they can drop pulley sizes so easily? this is encouraging, maybe KR isn't such a problem since they're intercooled...glad i happened upon that info :)

Our cars also use a cross refrencing graph. It uses charts to compare values from various sensors to calculate fuel control. If the one sensor is irratic or doesnt match a value in the tables the cel is on, and you might be in limp mode. Thought i might add that, im sure alot of you understand what im saying.

The device is also available from ZZ Performance : Here is more info ...

The AFC 2.2 (Air/Fuel Controller) is a micro processor based air fuel calibration device with digital display. The AFC performs this recalibration by receiving the Mass Air Flow (MAF) sensor’s frequency signal, digitally recalculating a modified MAF frequency value and passing this modified frequency to the Powertrain Control Module (PCM). The AFC can be setup to run in Standard Mode or Enhanced Mode and can be programmed to apply correction factors ranging from 1% to 255% of the original MAF signal.

To elaborate on this, correction values less than 100% cause the PCM to perceive less air is entering the engine and it responds by commanding less fuel be delivered to the engine. Thus, AFC values less than 100 pull fuel from the engine. Conversely, correction values greater than 100% cause the PCM to perceive more air is entering the engine, causing it to command more fuel be delivered to the engine.

This means AFC values greater than 100 add fuel to the engine. Two separate operational modes are provided. The current operational mode is announced briefly on the display during the AFC's boot up routine. The user can switch between operational modes on the fly without shutting off the car or resetting the AFC. Switching between operational modes as well as all editing is accomplished through the three interface buttons below the display. All set point editing is accomplished through these interface buttons. All data is automatically stored into memory when leaving any edit mode. This means all set point data is saved for subsequent system power ups.

Standard Mode – Applies a single correction factor to the entire frequency range (air flow range) of the MAF sensor. Thus, regardless of the MAF sensor’s frequency signal sent to the AFC, the AFC will apply the same correction factor.

Enhanced Mode– This mode provides 13 independent set points that allow custom fueling curves to be programmed into the AFC. The enhanced mode sets these 13 points in even 1,000 Hz intervals starting at 1,000 Hz on the low end of the MAF’s output range and all the way to 13,000 Hz at the high end of the MAF’s range. For MAF values between these defined set points, the AFC linearly interpolates the output frequency using the bounding set point values. Thus, the AFC creates a smooth curve throughout the MAF sensor’s output range.

The AFC is needed when the engine’s fueling demands have been altered by changes performed to the engine induction system. When induction changes have changed the fueling demands, the OBDII Powertrain Control Module (PCM) typically responds by adjusting the Long Term Fuel Trims (LTFT). (Fueling Trim values are a adaptively learned parameter the PCM uses to make minor adjustments to the fueling parameters to obtain the target programmed air/fuel ratio.) This unit allows adjustments to the Mass Air Flow (MAF) sensor’s calibration which impacts the fuel trims. With proper adjustments to the AFC, the LTFT values can be brought back near zero where the PCM functions optimally.

Technical Information:
* Plug and Play installation with OEM weather pack connectors
* Allows the MAF sensor to be fine tuned to the engine’s configuration
* Powered by voltage power to MAF Sensor with negligible power draw
* Single user set point correction in Standard Mode
* 13 user selectable set point corrections in Enhanced Mode
* 9 inches long from connector end to connector end
* Connectors keyed/indexed for proper connection)
* Compatible with all GM Mass Air Flow (MAF) Sensors
* Available in a variety of MAF connectors (E.g. GM L67, GM LS1, GM L67 to LS1 Conversion) to fit any vehicle/engine configuration
* An on board microprocessor executing proprietary computations and program algorithms is incorporated to achieve this recalibration with digital accuracy
* Detailed, color illustrated installation and user instructions included.

http://www.zzperformance.com/cobalt_ion/products1.php?id=452&PHPSESSID=c3ce0b2fa6f9c47cb2ddcfbe39d4f75b