ApexI Super-AFC
 

I did a search, and still no conclusive evidence that it won't work. I think playing with the fuel mixture could net some worthwhile gains, especially with an open intake and exhaust. I have seen it work on Several OBD-II cars, so why would ours be any different? They are selling like hotcakes for under $200 shipped, so I think 5-10 hp would be worth $$. Common gurus, I know someone has some legitimate input here.:)

Im 99.9% sure it wont work due to our wonderful OBD-II ECU. Like it has been said many times at wide open throttle, WOT, it kicks it in to a closed loop, meaning that it diverts back to pre-programmed ECU settings, no matter what :(. I really hope this is wrong because the S-AFC is a REALLY nice unit.

hey purePro5 how much did it cost to get the port/polish? how much power did u get out of that?

I did it all myself with a die grinder, and a dremel tool, and some sand paper, steel wool, etc. The hardest part was matching the ports from the man. to the head. I used the spacers as a guide. I ported the spacers to match the head, and the manifold to the spacers. Took all of one day and some of another. I live the way it feels. Very noticeable difference especially in torque. Gets off the line to a nice speed very quickly.
Anyway, back to the Apexi. Like I said before, I have seen several OBDII cars use these very successfully. There is still no proof that it works or doesn't work. Maybe I will give it a shot. I can get them pretty cheap.

The Super AFC will work on cars that operate in closed loop mode at WOT, but Proteges don't work this way. (Methinks that TrexPro's earlier post has open and closed loop mixed up; open loop is when the computer ignores the sensors.) There is plenty of "proof" that it won't work; all OBDII Mazda ECU's operate this way. :(

The only "piggyback" systems that will work on an OBDII Mazda are the type that are capable of overriding the ECU's *output*, such as the Unichip. Sensor-override systems like the Apex'i will only work at part throttle; all the Super AFC will do at full throttle is dress up your interior with its pimpy blue-and-white display. :rolleyes:

owned... thats correct. Sorry for the bad info.
Just like you said though there are many other cars that run the S-AFC with good results, MKIV Supra's for one. But like stated above Mazda ECU's ignore sensors at WOT. :(

Is there any way to adjust the throttle so it only opperates at 99% throttle? (Prevent the throttle from going 100%) This would prevent the computer from going into open-loop mode, but still getting about full power. It would then allow the use of the S-AFC.

the point IS to have open loop operation
after 4500rpm the apex will show some improvement
at 4500 the ecu will go into open loop at WOT while also alowing the secondary manifold plates open to allow more air flow for the increased load th tps is showing to the ecu

later from monster pro 5