[teal95]

I've got an 84 SVO that has wiring issues that I'm going to upgrade. (Whatever Ford used for wiring insulation in 84 can't take underhood heat and is falling off the wiring.) Being as it's one of the first EFI vehicles for Ford it has a lot of external control boxes that were later integrated into the EEC. I was planning on changing to an L* series (LA3) but am now thinking about using something newer as the only thing that's unique about the L is the VAM, boost control and low impedance injectors. Nobody uses low impedance anymore and I purchased a set of high impedance injectors for it so I'm not using that feature. I was going to swap to a MAF so I'm not using that features and I've never used the boost control anyways as I've always manually controlled it (usually by just bypassing the solenoid to get high boost all the time).

I would like to be able to run E85, so it would be nice to have an EEC that has this feature. I'm guessing that came after EEC-IV ended so I'm guessing it would require swapping to an EEC-V. Any recommendations?

The other thought I had was using an EEC from something with more cylinders but I believe I remember reading that turning outputs off (or on) that weren't original caused the output pins to change around. Any comments on this?

steve

[cgrey8]

...I would like to be able to run E85, so it would be nice to have an EEC that has this feature...

As long as the injectors are large enough to support E85, you are good there. However if you are wanting to run a tune that can auto-adjust to varying levels of ethanol from E0-85%, then that gets a bit more difficult. There were some applications that did that, however I think most of the earlier versions used a physical sensor to sense how much ethanol is in the fuel (likely measuring the resistance of the fuel and estimating ethanol content from that?).

There were other systems that did away with this sensor and guesstimated it, but they have their own set of complications. For example, they resampled what the likely ethanol content was shortly after crank when it detected a fuel tank refill. So while that sounds straight-forward, this implicitly means the EEC expects a returnless fuel system so it can crank the engine on whatever fuel concentration was used prior to the fillup. Then as the new fuel hits the system, it has to do a quick-response to possibly changes in ethanol concentration. It locks in that new learned concentration for all future cranks until the fuel tank is refilled. And of course, the EEC has to be monitoring the fuel level in the tank...all these are features not likely to be on your vehicle nor are you likely to want to add all that just for the possibility of running E85 from time to time.

As a result, you are far better off just having 2-3 tunes, one for pump gas, one for E85, and maybe one that can handle some middle-mix (~E40ish).

...The other thought I had was using an EEC from something with more cylinders but I believe I remember reading that turning outputs off (or on) that weren't original caused the output pins to change around...

I didn't remember this, but it also doesn't surprise me. However if you are going to be swapping EECs, there's likely to be other pins shifting around on you anyway. So while you have the harness apart to add/move whatever other pins got relocated, just update to whatever the new injector locations are (assuming you can know where the new pin locations are supposed to be).

Overall I think it's probably a good idea to convert to MAF. But I don't have a particular recommendation of EEC. The GUFx era EECs are hardly recommendable anymore since they are becoming so rare to find. The CBAZA EECs are probably going to be your go-to. I think they were used on both V6s and V8s. I guess they can be used on a 4cyl??? I don't know. If you did go with an EEC-V, you are now talking about a completely different EEC connector. So at that point, you are buying both an EEC and wiring harness. The details of retrofitting a significantly newer EEC into an older vehicle are fuzzy to me. I know it can be done by just disabling the right things. But specifically which one you should consider and go with, I have no clue. What complicates this is most EEC-Vs are EDIS. So you may have to convert your engine to coil packs, if it isn't already. I don't know much about your era engine to know if it has Duraspark, TFI, or EDIS. If it's already EDIS, then that would probably be a compelling reason to go with something newer anyway. The EDIS module didn't get incorporated into the EECs until the EEC-V era. I think even CBAZA requires an EDIS-X module for people that want to run EDIS on them. I know GUFx does.

I don't know if that helped any at all or just muddied the water. But those are my thoughts...

[teal95]

I'm not sure on the terminology but the last of the Mustang 2.3 were DPDIS and I would prefer to swap to that ignition system anyways as the turbo engines are hard on the ignition system. (I've already done one engine with putting in a crank sensor, but haven't run it yet.) With much of the underhood wiring missing it's insulation already I'm going to replace it, including the wiring to the EEC. I know the V gives me a lot more IO capability, if I can manage to use it is another question. It would be nice to be able to disable functions (DSO2...) and use those inputs for other items (WBO2).

Realistically this car would be a toy that I would only drive in the summer so E85 only would probably work fine. How well do you think it would work if I had to run straight gas if I opened up the fuelling adapt limits?

So the main question for me is what EEC-V is readily available and fairly well broken out for the cals?

How would I determine what pin goes where when it moves stuff around?

[motorhead1991]

Ideally, a standalone would be your best bet to be honest. Something like a Stinger PimpX and a Ron Francis harness to start fresh in one go. The PimpX is Megasquirt based so you'll need to set the tune up, but they're infinitely more capable than the EEC boxes.

[cgrey8]

Ideally, a standalone would be your best bet to be honest. Something like a Stinger PimpX and a Ron Francis harness to start fresh in one go. The PimpX is Megasquirt based so you'll need to set the tune up, but they're infinitely more capable than the EEC boxes.

My guess is they are going to be easier to migrate the application to than trying to Frankenstein a stock computer and harness.

[motorhead1991]

Ideally, a standalone would be your best bet to be honest. Something like a Stinger PimpX and a Ron Francis harness to start fresh in one go. The PimpX is Megasquirt based so you'll need to set the tune up, but they're infinitely more capable than the EEC boxes.

My guess is they are going to be easier to migrate the application to than trying to Frankenstein a stock computer and harness.

Correct. Rolling an engine forward to OBD2 is no fun (as I'm sure you're aware), so if one is going through the trouble of rewiring, why not start fresh?

I'm all for keeping the EEC in most cases but in this one....