In about 2 weeks we should be firing up my wife's built H22A w/ 11:1 compression, portflow head, and Jun cams and we need some tech help on what we should set the fuel settings on her V-AFC until we can get it broken in and then to a dyno w/ a wideband O2 sensor. We're running stock ecu, fuel pump, injectors, etc. so we're going to have to make the corrections, at least temporarily, utilizing the V-AFC. My initial plan is to set the vtec crossover point @ 6,000, increase fuel 5 percent over stock maps across the entire power band, use 1 heat range colder plugs, and retard the ignition timing to around 13-14 degrees to help prevent detonation due to poor air:fuel ratio. Any ideas or suggestions would be greatly appreciated.

 

You're gonna need more fuel than that vafc will add.

 

Yah, the thing with the AFC is that you can trim(take away) fuel without any problems, but when you try to ADD fuel, you can only go so far before getting a MAP sensor code. Once you go past about +10-15% fuel enrichment, the extra 10-15% the AFC adds to the MAP signal in order to get the stock ECM to add fuel will tript he MAP sensor malfunction code. The ECM will think you're seeing boost, basically. You might be able to get around that with a voltage clamp, but I don't know how you would get that to both clamp MAP voltage, yet still have the ECM add fuel.

 

You need a new pump at the very least, but I'd invest in a completely new fuel system while you're at it.

 

Pump, injectors, FPR, and some ecu work.

 

well... here's an idea... turn it up till ya see either a code, or black smoke, then back it down a notch. lol

That's what we do to mom's XR4TI... Turn the boost controller up til ya hear detonation... then back it down a little. LOL

I'm just kidding, don't take that advice ;-)

Harry