Apexi SAFC

[A31_Cefiro]

Hi guys,

I've seen some posts on the Apexi SAFC. What functionality does this allow amodified car? I know it change fuel mixtures is that it?

Thanks,

[400HP]

this is from a sales website:

The second generation Super AFC follows the highly successful Super AFC in an upgraded package. The Super AFC is a vehicle specific fuel computer that modifies the air flow meter signal/pressure sensor signal and allows the user to either richen or lean the fuel mixture. Adjustment ranges from +/-50%. The Super AFC boasts an 8 point adjustable fuel curve with 500 RPM increment setting points. The Super AFC also allows the user to adjust fuel enrichment according to either LO/HI throttle positions. The AFC also cures the erratic idle problems associated with open atmospheric blow off valves on hit wire air flow meter equipped vehicles. Monitor Mode shows analog meter faces, Y Graph Display, Numerical Display, Peak Hold, Replay Mode, 1 point/10 point and ghost map tracing. All correction factors are also displayed in percentages. All values and graphs are displayed through the exclusive VFD (Vacuum Florescent Display) screen

[A31_Cefiro]

Is a S-AFC going to let me run a bigger AFM (Z32 type)? Will it also let me tune the most out of my mods?

Mods I currently have on or being fitted are:

K&N air pod

FMIC

exhaust

High Flow fuel pump

Is the S-AFC really necessary with the RB20DET? How tuneable is the standard ECU on these suckers? Would I be better off looking at an aftermarket ECU?

Thanks!

[Silver-Arrowz]

With a SAFC you should be able to run the Z32 AFM. Can someone confirm this.

The standard ECU is tunable and in my opinion, would give you more power output than just the SAFC because the SAFC adjusts the air/fuel mix, not the ignition timing. If you tune the ECU, you tune both A/F and ignition.

[400HP]

Silver-Arrowz - doesn't it depend which eCU you have. On my R33 GTR I'm quite sure its not tuneable. But yes the SAFC doesn't allow you to adjust ignition timing.

I'm not aware of the the SAFC having a special setting for Z32 AFM. The AFM I thought simply takes in readings from the factory sensors for fuel and oxygen and adjusts then slightly.

[Silver-Arrowz]

Oh yes, your right there. Forgot about that. R33 ECU is not tunable.

With the Power FC it simply changes the voltage signal to whatever the z32 is. I'm thinking that the SAFC can adjust the A/F mixture to suit it, since it taps into the air flow meter anyway.

[Guest INASNT]

if u want to get technical its not exactly changing the a/f ratios.

It really just tricks the ecu into thinking u r getting less air flow than u really r so that it doesent run so rich!

Its what u call a band aid solution, get the factoru r32 ecu retuned u will get better results.

[dojobi]

Inasnt: it DOES change the A/F ratios. It just does it by tricking the ECU into thinking less/more air is coming in at any point in time than really is. Because of that, it adjust the amount of fuel it gives it. The only reason a retuned ECU would be better is because you can change things other than the air/fuel ratios like ignition timing. If you just did the fueling on the ECU though, it would be just as good.

[Guest INASNT]

Originally posted by MIC33R

Inasnt: it DOES change the A/F ratios. It just does it by tricking the ECU into thinking less/more air is coming in at any point in time than really is. Because of that, it adjust the amount of fuel it gives it. The only reason a retuned ECU would be better is because you can change things other than the air/fuel ratios like ignition timing. If you just did the fueling on the ECU though, it would be just as good.

i know mate, i got 1!

[dojobi]

same here Sorry about that. I was just defending my "band aid" SAFC

[Guest INASNT]

Originally posted by MIC33R

same here Sorry about that. I was just defending my "band aid" SAFC

It ok for what it is, lot of tuners have told me go for power fc, which is next on my list

[JimX]

It all comes down to cost. You can get an S-AFC for around $600, whereas a Power FC is over double that. You probably won't get twice the power gains with a Power FC! (it depends on your setup though). But the S-AFC is better than nothing.

My advice would be to get whichever you can afford. If you don't have much spare cash, get the S-AFC, then sell it and upgrade to the Power FC once you can afford it. That's what I'm doing

Regarding the bigger AFM, do you just change the meter itself or all the plumbing behind it? Just looking at my intake it all seems to be uniformly the same diameter down to the turbo, I can't figure out what benefits a larger AFM would give.