02-05-2013, 08:41 AM (This post was last modified: 02-05-2013, 08:46 AM by Eliminator SS.)
I'm helping a friend work on his 88 Turbo coupe, I myself have built several cars, mostly muscle cars/hot rods but have got into turbocharged DSM's in the last couple of years. My friend wants to start modding his car and just bought an extra Garrett GT3076R ball bearing turbo I had and wants me to install it on his car. My concern is going bigger with the turbo necessitates getting into adjusting the air flow metering and fuel metering. I have a standalone air fuel controller off of one of my DSM's that I'd like to try wiring into the ECU. Has anyone ever done this before?
I am by no means an expert on engine management, but I don't think there's much of anything that can be done to the factory pcm. I think the only thing you can do with the factory pcm is to get a hold of a J3 adapter and have a chip burned for larger injectors. I could certainly be wrong though. A lot of people go with a megasquirt(or microsquirt?)-based standalone, but that replaces the factory pcm entirely. Others convert to speed-density, but I have no clue what's involved with that. Sorry - I'm not much help on this topic.
Basically what the SAFCII does is wires in between the Maf and injectors and the ECU. The SAFCII then manipulates the signal sent to the ECU from the MAF as well as manipulates the injector dead time and pulse width. This allows you to use the factory ECU.
I guess I need to know, does the factory Mass Air Flow sensor use a 0-5v signal? And does anyone have a pinout print for the ECU?
1971 Camaro RS/SS, Built 355 Small Block, 426hp. Muncie 4spd. Ford 9" rear.
1979 Camaro Z28, 1974 Corvette LT1, TH350, WS6 TA Rear Axle.
1997 Mitsubishi Eclipse GST, AWD Conversion, Built 6 Bolt 4G63T, Custom FMIC, FP3065 Turbo, 579hp.
Yes, the air meter uses a 5V reference and outputs from roughly .3V to 4.5+ V depending on air flow. The TC (stock) doesnt use a hot wire mass airflow meter, it uses a mechanical vane air flow meter (VAF or VAM) made by Bosch. The PCM is programmed to account for the mechanical characteristics of the VAF, which are unlike a hot wire MAF. The transfer function of the VAF is well known. SInce all your device does is alter the output signal, it may very well work with the VAF.
The stock EEC IV can be reprogrammed with a chip connected to the J3 port as Brian said, or can be tuned with Quarterhorse / Binary Editor, or the older less powerful EEC tuner or Tweecer.
Jeff Korn
88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
11 Crown Vic Interceptor
14 Toyota Camry (wifes car)
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
Its going to be interesting to say the least to figure this out. Tell you what though, if I can figure this out and make this work, its a much cheaper and more simple solution to tuning.
Does anyone have a pinout diagram for the ECU?
1971 Camaro RS/SS, Built 355 Small Block, 426hp. Muncie 4spd. Ford 9" rear.
1979 Camaro Z28, 1974 Corvette LT1, TH350, WS6 TA Rear Axle.
1997 Mitsubishi Eclipse GST, AWD Conversion, Built 6 Bolt 4G63T, Custom FMIC, FP3065 Turbo, 579hp.
Here's the pinout (Attached). You're looking in the LA3/LB3 column. There are numbers on one side of the 60 pin connector that will tell you which pin is which.
02-07-2013, 08:25 PM (This post was last modified: 02-07-2013, 08:40 PM by TurboE.)
Sounds pretty cool and interesting. I'm not sure the typical price and obviously if you have the apexi device already laying around it's worth a look. This was a quick price search?
To me any good result is worth finding, cheaper and easier is always better!! At the time moates looked like the best option to me pricewise. Now the pimp looks good to.
Without looking to much into it you could most likely fine tune the engine, for example increasing voltage as more fuel is required. However you will most likely find that you will be at full voltage (4.5V or 5V) before the engine/turbo combination is at full rpm/throttle. As you've probably already considered if you use larger fuel injectors (lieing to the EEC) you will get more fuel than desired (same pulse width and more flow rating as the EEC factors in the injector size as a scaler) and decreasing the VAM signal to reduce fuel may work. The ford EEC uses a combination of parameters to calculate the injector pulse width. There could be other factors involved but might be worth a try? From memory most of the timing curves are rpm vs. load but I could be off on that been a while since i looked at it. Another thing you might find is that at X airflow the VAM will be pegged and you will run out of scaling to measure more air (why speed density is used with a 3 bar MAP sensor) at that point the you could try to simply consider that full throttle and give it enough fuel for the max over measured flow and know it will be a little rich prior to reaching that flow, or some guys adjust the spring on the VAM to allow a higher flow to read full range (4.5/5V). Maybe a combination of both will allow you to adjust for both extremes of the fuel curve? Good luck tuning!
