I was wondering if anyone has tried to use an AFC with bonneville'* before. I was thinking A Piggy back like the Apexi NEO or the AEM FIC (Fuel Ignition Controler) could be used for injector swap and tuning without having to send the PCM off every time you wanted to change something. I was thinking of using it to dial back some larger injectors for a potential E85 conversion.

I apologize if I am way off with this tuning method but It works fine for budget DSM builds that I am used to working on.

I don't recall anyone dong this before, but it sounds like a great idea. And we always like to encourage different thinking. If you do this I would like to see a write up about it.

I know with the DSM ECU when you start increasing injector size (you show the computer less airflow with the AFC to compensate) the computer starts adding ignition timing, so I would only step up to a 42# (~450cc iirc) injector since its ~20% bigger than stock bonnie injectors (iirc again) and E85 would take ~20% more fuel. Then, the AFC would only have to cheat the computer for a smaller amount of airflow to get to stoich and the timing wouldn't be as far off, and if there was a small amount of timing added the E85 would have no problem keeping KR (knock in my lingo) to a minimum and if you ended up losing timing that just means compensate with more boost .

I dont know what the stock fuel pump is capable of but an inline would be easy enough to add if necessary.

42.5# Lucas Injectors - $239.99
AEM UEGO Gauge-Type Wideband - $218.11
Walbro Universal External In-line Pump - $119.00
Apexi AFC Neo - $359.00
$936.1 Total, which is fairly steep, but all that stuff can be had for cheap on my DSM forums since a 450 injector (low impedance though so a resistor pack would be needed for this application) is stock for us DSM Guys! and most people start with AFC'* then step up to stand-alones for high power motors (675+HP, 35+Lbs of boost) I have seen injectors given away and AFC'* as low as $100.

This looks like a great project. I've seen used 42.5# for $180.