I would appreciate this stay in the 2nd gen. tech section, simply because the SAFC section is unpopular, and this is "2nd gen. tech" relevant...

That being said, I have some confusion as to what the best method will be to tune down the 23% increase in fuel.

When working with an SAFC, you are given two maps to play with; the "low throttle" map and "high throttle" map. You are also allowed to set their "throttle" point, but I'm having a hard time understanding what this actually means.

Since these 680's are going to be dumping fuel at idle, or 0% throttle, should I have my low throttle map come on at 0%? If not, can someone explains what exactly the throttle points mean, or how they work?

Thanks,

 

Also, does anyone know why my maps are "upside-down"? If I subtract fuel in the graph--it actually adds fuel...

I've read about this in the past, but don't remember how to combat it.

 

You need to go back and reset your SAFC. Maye Initialize it and then go and put the CYL to 4, the ARROW UP AND TO THE RIGHT and SENSOR TYPE to FLAP and IN/OUT to 05 and 05. That is your upside down backwards problem.

A person REALLY needs a wideband when playing around with a SAFC etc. imho

The six eightys should have gone into the secondary position and not the primary imho.

 

Would it be possbile though to lean out the primaries at low throttle and set high throttle richer. Or would hi throttle only be for the secondaries coming on? Kinda curious about that.

ErixHVN to eriksseven. I like the handle, Got a good ring to it.

 

I'm really, really incompetent using a SAFC.

I find that when you change the HIGH or the LOW it effects the OTHER. Like removing 30 percent at the 3000 rpm level on the HIGH and leaving the LOW as it was, that change in the HIGH will effect the LOW.

Such as: make a change as describe above and leave the LOW alone at no change at all. Then go for a drive using little pedal (stay in the LOW). Now look at the CORRECTION percent on the screen. It ain't a gonna be zero correction. It will show a correction even though you didn't change anything in the LOW settings.

Now go back to the very first sentence I wrote and read it again. In other words mess with your car and see if I'm right or wrong about what I wrote.

 

wow.. I dont know if the SAFC can idle those 680s.. Maybe, maybe not, but it would require an o2 sensor to make the adjustments.

 

Do it right. Swap them into the secondary position. Then take it to a professional tuner.

 

Hey, cool! Or I could leave them in the primary position and tune them myself... BTW, I asked a simple question and instead of answering (or attempting to answer), you simply told me to do something retarded and then insulted me...

And yes, today was a complete success. We tuned using an LM-1 wideband, the S-AFC was hooked up to the pressure sensor, the low-map was set to 0%-60% throttle and set anywhere from 23%-36% depending on the RPM etc. 60% throttle is right at "0 PSI", so we used that as the transition point from the low-map to the high-map. We tuned for mid-14's for cruising, and low-11's for WOT or anything above 60% "throttle".

The idle is smooth with a around 13.5-13.7 AFR.

The car absolutely RIPS in 4th gear and I'm really, really happy with the results.

Some performance mods:

~9:4:1 s4 N/A rotors
~street-port
~hybrid TO4/T04B s5 turbo
~ThunderFab DP/MP mated to Apexi (dual) N1's
~R-Tek 1.7 chip
~Apexi S-AFC
~Greddy Profec-B EBC
~680cc primary injectors
~890cc secondary injectors
~Walbro 255lph. fuel pump
~TB mod etc.

Currently running 11-12psi

 

Yeah, I tried initializing it several times, but every-time I shut the car off I discovered it would erase my changes and revert back to the old Honda map that the previous owner was using... So yeah, the 'sensor' setting that it kept switching to was hot wire, not flap. Regardless, I finally got it to save.

 

Well I'm sorry for not fully understanding what you were doing but that's what happens when you provide only a fraction of the relevant info. No mention of the bigger secondaries, other mods, tuning method, anything. Just what sounded to me like a very noobish tuning question.

To tune for 23% bigger injectors, set the base corrections at -19% (1 / 1.23 = 0.81; 1.00 - 0.81 = 0.19).

Note that fuelling during cranking is not determined by the AFM, so flooding on start is a likley possibilty from increasing the size of the primaries.

And where's this alledged insult?

Don't forget that the S-ACF interpolates bewteen the low-throttle and high-throttle settings. So if your throttle settings are 50% (low-thr) and 70% (hi-thr), and your fuel corrections are say 0% (low-thr) and +20% (hi-thr) at a particular rpm, then at 60% throttle (halfway between the lo-thr and hi-thr settings) you'll get a +10% correction.