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Topic: EDIS conversion? (Read 387 times) previous topic - next topic

EDIS conversion?

Looking at getting an electronic distribution system going with the Ford EDIS-8 parts. Has anyone looked into this in the past? I've read various pages and discussions on the topic, but it's all inconsistent and not as complete as I'd like.

The benefits are more precise timing control  (I have a Quarterhorse on my EEV-iv), and factory multi-spark ignition (up to 3 pulses per cylinder). Power improvements are minor, but more consistent, and people that have performed the conversion claim idle smooths out greatly, even when coming from a fresher TFI setup.

To start, it sounds like the following is needed:
- EDIS-8 module and wiring harness.
- EDIS mounting brackets or DIY.
- Explorer cam position sensor shaft ( for oil pump, cam sensor itself won't be used).
- 1996 F150 50oz balancer with embedded trigger wheel, or 36-1 trigger wheel adapted to existing balancer. Explorer balancer won't work as the pulley and balancer are one, but pulley is wrong depth. Addon wheel required machine work to remove the extra thickness added by the wheel. Serpentine alignment.
- Custom VR-pickup bracket. Seeing mixed things about the Edelbrock 4251 timing cover with the bosses built in. It's reverse water pump, but looks quite different than factory?
- VR pickup sensor.
- 2 coil packs and wires.
- EEC-IV settings reconfigured via tuner to enable EDIS functionality.
- One additional pin may be needed to wire into the ECU? Sounds like it's 2 existing signals and a new one.
- Some additional wire, solder, heatshrink for existing existing harness modifications. Some wire may need to be shielded.

Would like to start getting parts this week, but don't want to purchase the wrong parts, or purchase parts that I don't necessarily need.
1988 Thunderbird Sport

Re: EDIS conversion?

Reply #1
Some useful wiring infromation found elsewhere:

TFI SPOUT --> EDIS SAW (pin 3)
TFI PIP --> EDIS PIP (pin 1)
TFI Ground --> Ground (pin 7 or 10 or both)
TFI Ignition On --> EDIS Ignition On (pin 6)

Coils A-B-C-D --> EDIS Pins 8,9,11,12
Crank Sensor --> EDIS Pins 4,5, and shield goes to 7.

That's really about it. TFI yellow/tan tach signal goes to EDIS pin 2. Without this you have no factory dash tachometer, but some cars apparently don't work with this and need an additional solution.

Looks like we can get all the wires we need at the existing TFI module.
1988 Thunderbird Sport

Re: EDIS conversion?

Reply #2
You'd be the first person to do the EDIS conversion here. I'm interested in seeing how it goes. I've not had many problems with the TFI distributor system but good TFI and PIP modules are getting harder to find. I've heard that even the Motorcraft versions of those parts are having issues out of the box.

I'd really like to do a COP conversion but that would require a Pro-M ECU and harness. By the time you add it all up the cost for that setup almost exceeds what I spent building the engine/trans combo for the car.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Re: EDIS conversion?

Reply #3
It seems the easiest way to solve the most difficult part is to weld a 36-1 crank trigger wheel to the crank pulley, and fab a bracket that bolts to the waterpump bolts, as a extension for the VR sensor. It'd be cleaner to have this on the backside of the harmonic balancer and a lower profile VR bracket, but that is more concerning for me as I don't know enough about how the balancers work.

I've already gone through every eec-iv discussion I could find on searches, and some megaquirt discussions. I'd like to focus my research now on  MS-specific discussions about adding a crank position sensor.

I'm not sure how people are getting by with just "sandwiching trigger wheels" beween parts and not welding.  Your trigger wheel wouldn't be guaranteed to not creep a little by doing this. Of course  this would also require removing some material from a crankshaft pulley spacer due to the additional thickness taken up by the trigger wheel.

Once I figure out this mounting, I will likely just CNC out parts for a bracket (can be quickly reproduced!), and wire in the EDIS module, letting it sit loosely while I test. EDIS and coil brackets can be made up later. The only difficult part appears to be that crank trigger.

I welcome any ideas on crank trigger wheel mounting, especially if you know which part of a harmonic balancer can be slightly out of balance.
1988 Thunderbird Sport

Re: EDIS conversion?

Reply #5
I had already seen that doc, and a couple other docs on the eectuning forum. Nothing covers a perfect solution for the crank trigger wheel, but in front of the balancer seems to be common. Those timing covers with the bosses are also long unavailable. That one does look like the Edekbrock timing cover, but the angle of the WP input and outlet are different than factory on both. Would likely have a bit less water flow/turbulence from the perpendicular castings compared to our stock timing covers and water pumps, but I believe they should bolt on and seal up correctly.

An issue with a lot of information online is that it's from over 10 years ago. Many of the parts and companies available then are gone today. A lot of the photos online (photobucket) are also now locked/blurred due to service changes.

Looking at this last night, I'm likely going to just pull my crank pulley and have a trigger wheel welded and balanced to it at the machine shop. Similar to the photos in that doc, and old discussions on other forums of doing the same.
1988 Thunderbird Sport


Re: EDIS conversion?

Reply #6
U-pull-it places around seem to charge too much for multi-port coils and the cam synchronizes, so I ordered a few parts online for what I expect to pay locally. $90 for EDIS8, two coil packs, wiring harness and plug wires, and explorer synchronizer shaft. Just need a vr sensor and trigger wheel, and I'll have everything I need to get this project completed. Once I figure out which trigger wheel to grab (many seem to get one from diyautotune), I'll get it and the crank pulley off to the machine shop.
1988 Thunderbird Sport