Will MJLJ work with a stock Ford 2.3 turbo ECU?

[914turboford]

I am trying to build a 2.5l stroker turbo engine using a block from a '99 Ranger 2.5 with upgraded pistons and a head from a 1986 Thunderbird turbo coupe. I would like to use the stock ECU to run fuel delivery and the Megajolt to run timing.

Can the Megajolt unit send the proper signal to the ECU so that it can control the fuel?

Brian
Tahoe

[MartinM]

Megajolt is ignition only, and is highly unlikely to be able to send any relevant signals to a fuel ECU

However, is is possible to run a fuel ECU and a Megajolt concurrently - which is exactly as I do on my Peugeot rally car. I have an MJLJ EDIS setup (MJLJ unit, VR sensor, EDIS module and wasted spark coil) for the ignition and the orignal Peugeot fuelling ECU. Works fantastically well

Of course, the best soltion for you could be the Megasquirt'n'spark, but that's dealt with on a completely different forum (http://www.bgsoflex.com/megasquirt.html)

[914turboford]

What type of fuel ECU are you running? Is it a stock Peugot ECU? If so, does it need timing data to function properly? If so, how are you providing that?
'73 914,'86 2.3T, Escort trans, C5 18/17" rims. '74 Civic on '89 RT4WD pan. '75 Volvo 245 4x4, D30's F&R, '97 GM 3.8, 700R4. All run/drive. Near Tahoe

[MartinM]

D'ya know - I don't know! Well, it escapes me right now anyway.

I took a standard car (fuel ECU and distributor ignition) and just provided an alternative spark system - left all the original spark stuff in place, which in fact still drives the tacho. Even left the original plug leads in place (cable-tied out of the way) so that I can revert easily to original if I get any MJLJ/EDIS problems during a competition.

You near Tahoe, as in Lake Tahoe, as in snow resort at this time of year? Well cool if you are - we're coming out to Colorado (Breckenridge) in March for 12 days skiing...

[914turboford]

So you are using the stock ECU it sounds like. Do you have a wiring diagram of how the Megajolt/EDIS interfaces with the car's ECU?

Brian
Yes, we do get snow around here. We live about 50 minutes from Tahoe at about 4000 feet elevation in a town called Pollock Pines, CA. For the last two weeks we have gotten nothing but rain and there are flooding concerns in the Sacramento Valley.

'73 914,'86 2.3T, Escort trans, C5 18/17" rims. '74 Civic on '89 RT4WD pan. '75 Volvo 245 4x4, D30's F&R, '97 GM 3.8, 700R4. All run/drive. Near Tahoe

[Paratime]

I believe that it is highly impractical to interface the MjLj with any stock fuel injection ECU. Most engine management computers control ignition timing, and expect to see a signal back from the ignition module that confirms timing is at the value the ECU is trying to set. Building an interface that will send back a false signal of what the ECU expects to see, while still running the timing curve with the MjLj is an extreme headache. The system that most use, is to leave the current ignition system and ECU completely intact, and just disconnect the coil, or ground out all the distributor towers. Thus, the ECU is "fooled" into thinking that the engine is running normally. The ignition module will send all the typical signals and fuel will be metered as usual. Many ECU's use the distributor pick up to synchronize the SMPFI as well. Also, leaving the distributor in place will greatly improve oil pressure, if the oil pump is driven off the base, as in most US V8s!

[brentp]

Yes, that's an insightful comment. Let the ECU think that it's really controlling the ignition timing, but disabled at the distributor.

So for engines driven off the same gear or shaft as the distributor, what is the typical configuration for any crank fired system? There might be a dummy distributor that retains the shaft yet has just a plug or block-off plate at the top.

[Paratime]

This page has a couple clickable pictures of an oil pump drive unit used for DIS cars. This engine uses a front cam pickup for SMPFI, as I recall.

http://www.v6z24.com/howto/oring

[914turboford]

Sounds interesting. What I am trying to do is to use MJLJ on a four cylinder short block that came from the factory equipped with EDIS, a 1999 Ford Ranger pickup 2.5 liter. Thus there is no provision for a distributor. I want to add forged turbo pistons of the same bore from a 1988 Ford Thunderbird and use the cylinder head from the turbo motor as well.

The 2.3 turbo motors can handle 22 psi boost with these pistons and heads. So I wonder if there is another way to fool the ECU into thinking it is controlling timing.

Incidentally, I believe the ECU for the 1988 2.3t that I want to use is called an EEC-IV, which I noticed is the general label for the EDIS ECU identified on this site.

One other question, what is meant by "grounding the distribultor towers"?
Brian

'73 914,'86 2.3T, Escort trans, C5 18/17" rims. '74 Civic on '89 RT4WD pan. '75 Volvo 245 4x4, D30's F&R, '97 GM 3.8, 700R4. All run/drive. Near Tahoe

[914turboford]

Thanks for the help. However, that is not relevant to what I am trying to do. The block I want to use has no distributor hole at all. It comes factory with EDIS. It is a 1999 Ford block. What I am trying to do is use an older (1988) Ford turbo ECU with the 1999 Ford short block.
Brian

'73 914,'86 2.3T, Escort trans, C5 18/17" rims. '74 Civic on '89 RT4WD pan. '75 Volvo 245 4x4, D30's F&R, '97 GM 3.8, 700R4. All run/drive. Near Tahoe

[Paratime]

Grounding the towers means running a regular wire from the engine block to each of the distributor towers. Normally the coil would just be disconnected, but some ignition modules read the voltage spike the coil makes when it fires, for diagnostics. For these systems, the coil must still produce a small spark, or the ECU will go into limp mode.

EEC-IV means Ford's Electronic Engine Control generation 4. Most of the cars that used this generation had distributors, and MAP (cheaper than MAF) fuel computation. These systems will not fire the fuel injectors unless they see a continuous series of pulses from the distributor. They will also not meter fuel correctly if the cam, compression ratio, intake manifold, or fuel injectors are changed, even one step. The few systems that used MAF, like the Mustang 5.0 in the late 80s and early 90s, are the ones usually used for engine modifications.


I haven't worked on a late 80s turbo 2.3 in a few years. I believe, though, that they used a traditional TFI distributor. If this is the case, then using the fuel computer with a non distributor block, will be almost impossible. It would be far cheaper to buy an 88 short block from a junk yard, then to design and build electronics to simulate the distributor signal to the ECU.

[914turboford]

My original intent was to use the stock Ford 2.3t LA3 computer with EDIS. I have done some additional research. Apparently the PIP signal generated by Ford TFI/DIS are of the same form and frequency as that generated by an EDIS module. However, the ECU's timing signal is different . For EDIS the ECU sends a signal (called SAW-Spark Angle Word) which the EDIS module interprets to fire the plug at the right time. For TFI/DIS the ECU fires the plug in a more direct manner using a signal called SPOUT- Spark OUT.

Based on what I've learned so far this is my latest plan: Build a Megajolt system to run the ignition system. Tee into the PIP line coming from the EDIS module to send a PIP signal to the LA3 ECU. This will give the LA3 the rpm info it needs. I would then dangle the SPOUT wire. The Megajolt would control the timing and the LA3 would never know the difference. To my knowledge the LA3 has no way of checking the timing. The SPOUT is merely a delayed PIP. The ECU receives a 5v square wave called PIP from the TFI/DIS and returns a 5v square wave called SPOUT.

Any thoughts?
Brian


'73 914,'86 2.3T, Escort trans, C5 18/17" rims. '74 Civic on '89 RT4WD pan. '75 Volvo 245 4x4, D30's F&R, '97 GM 3.8, 700R4. All run/drive. Near Tahoe

[Paratime]

Please clarify a point for me. I have looked through some of my references, and they show the 88 Thunderbird as being the only 2.3 with a turbo. This engine is listed as only having a distributor, and not distributorless ignition.

Do you have an 88 2.3 turbo with no distributor?

[DPDISXR4Ti]

Looks like this thread went idle - I'll step in and answer your question, since it looks like Brian gave up. First, there were three different cars that used the 2.3T in the mid/late 80's: T-Bird TC, Merkur XR4Ti, and Mustang SVO. BTW, these cars all used EEC-IV with TFI/disty and VAM for air metering.

It is very easy to convert these motors to DIS using parts from the early 90's 2.3 Mustangs and Rangers. DIS looks precisely the same as TFI/disty, from an electrical perspective.

EDIS is a different deal however; as Brian referenced, PIP is the same, but the SAW signal and supporting hardware is entirely different from SPOUT, as used with EEC-IV (DIS or TFI/disty).

As a result, I too am inclined to believe that MJLJ could be used to control timing of an otherwise stock EEC-IV setup, which could continue to provide fueling. I believe that all EEC-IV needs to do that job correctly is PIP. Bear in mind, fuel delivery is not a timing precise event like ignition. It just needs to deliver the proper amount of fuel, IN BATCH, for each revolution.

As a result, I have no reason to believe this won't work - I just don't think anyone has tried it yet.

Brad