I recently blew the engine in my TII. Since then I've replaced it but i want to ensure that it doesn't happen again. So i've decided to put in 680cc injectors as secondaries and a bigger fuel pump. As we all know, this will result in a richer mixture which will also cause performance problems.

I keep hearing about the S-AFC, but i don't understand what it does. Does it control fuel amounts? or does it tell the ECU different things about incoming air flow so that the ecu can decrease the amount of fuel? If that is the case, will decreasing the amount of fuel cause a lean condition (which would again pop my engine)?

Please clarify the purpose and the method that the S-AFC uses to fix the fuel richness problem encountered by an upgraded fuel system.

Also, are there any other methods available to alleviate the rich mixture problem besides the S-AFC that won't cause my ********* to fall off in fright?

 

S-AFC = Super Air Fuel Commander.

This "piggyback" computer allows you to control the amount of fuel in your engine. I think you can adjust the amount of fuel for every 1k (or every 2k) rpms all the way to your redline.

Using the S-AFC wont cause a lean condition unless you set it that way. I think you would get better answers if you post this in the ECU section. You can copy someones S-AFC settings that have the same mods done to their car and use them on your S-AFC. If not, dyno time is required for best results.

 

Okay, to dispell ALL rumors(since I am the S-AFC king).

S-AFC Stands for Super Air Flow Converter. If you don't believe me, look at the box that it comes in...since I bought one new, I should know.

The safc works by interrupting the air flow signal coming from the MAF meter. Depending on what the user wants, it can increase fuel + or - 50%.

You have a total of 8 blocks, depending upon where you want it to read most accurate, you can have them at 1000 rpm/2000rpm/3000rpm etc to 8000rpm...or you can have them at 1000rpm/ 3000rpm/3500rpm/4000rpm to 7000 rpms....you get the picture right? increments of 500 rpm with a total of 8 blocks.

It has a high throttle and a low throttle setting. Throttle position is determined by a +5 volt coming from the tps. Depending upon where you set the low throttle/high throttle position(it's on a percentage basis i.e. XX% of 5 V), determines when it switches from low to high.

It increases/decreases fuel by taking the MAF signal and "fooling" the computer that more(or less) air is going into the engine...thus more(or less) fuel will be added.

The SAFC does NOT control injectors ...it will work to control fuel%. Your ECU control the injectors. The SAFC simply tells it more or less. But you have to remember that 5% on a 550CC injector vs. 5% on a 720cc injector is different.

 

So... If i were to put in an S-AFC on my stock TII, would I be able to fool the computer into running a bit richer by having the SAFC report that more air is going into the engine? This technically would be running rich though, right?

Is there an alternative that would compensate correctly for the amount of air going into the engine after modifications (something that won't bust my *****)?

If fuel economy doesn't change much, then I'm ok with it, but if I end up only getting like 2mpg then I need something else.

 

bump

 

yes you can make it run richer....up to 50% richer, or 50% leaner...thank you please drive thru