Ford EDIS Megasquirt Conversion 289 302 351

January 2010

Justin Finney provided us with a writeup on use of a DIYAutoTune MegaSquirt EMS systems, trigger wheels and installation of a Ford EDIS ignition system on a 1966 Bronco.

Ford EDIS Megasquirt Conversion 289 302 351


Why Do this Conversion

  • Bigger spark (no spark lost from the rotor to cap)
  • Precise timing (timing chain slack and distributor gear wear can throw off timing)
  • Control timing curves from your computer
  • Larger spark plug gap
  • Proven Technology (used on ford cars and truck for the last 15 years)

Parts List

I started considering this conversion when I switched my 1966 Bronco to Megasquirt. Having fuel injection when off-roading is a must. With fuel injection you do not need to change jets or metering rods at high altitude. Now I have immediate throttle response and can stomp at any angle. I used a Holley-projection 700 CFM throttle body.

Engine Specs

  • 289 Cubic Inch engine
  • Edelbrock Performer RPM Air-Gap Manifold
  • Holley Pro-jection 700 CFM Throttle Body
  • Megasquirt II with 3.57 Board
  • Heavily ported heads, hardened seats, Enlarge valves, Comp Cams triple springs
  • Comp Cams Roller Rockers
  • Comp Cams retro fit roller cam conversion XR282RF-HR10
  • Headman Headers
  • Victor Series Water Pump
  • Billet Pulleys

Building The Trigger Wheel and VR Mount

I used my drill press to drill the 4 evenly spaced holes in the trigger wheel. I lucked out because I basically eyeballed it.

Parts Trigger Wheel VR Mount

Building the Crank trigger wheel and VR Mount.

EDIS-8: missing tooth is exactly five teeth (50�) ahead of the VR sensor.

VR Mount VR Mount VR Mount

Having an extra timing chain cover made building the VR sensor mount allot easier. Most off this was just eyeballing. No formulas or calculations.

VR Mount VR Mount VR Mount

Parts Preparation

Sand Blast Cabinet

Bead Blast

Harbor Freight Powder coating machine

Powder Coat

Powder Coated and ready for Oven

Powder Coat Powder Coat

Put in Oven

325 degrees for 15 Minutes. Beware! This is sure to activate angry wife syndrome.

oven oven

Finished Wheel and Mount


First Mounting

Test test

Testing VR Mount

Mounting VR VR Mounting VR Mount

Cam Position Sensor off an Explorer 5.0. The only point of this part is to drive the oil pump and cover the hole left by the distributor.

cam sensor

Mounting Coil Packs and building wires. I used the coil pack mount off a 5.0 Explorer.

5.0 V8
cylinder locations
coil idetification
4 7 ///////////////3 5
8 2 ///////////////6 1

Coil Packs Coil Packs Coild Packs

Mounting the EDIS Module and Megasquirt. This is Mounted under dash. Megasquirt is awesome.


Finished Product


I was using an MSD mechanical advance distributor and 6AL before the upgrade. Now I can control timing curves through Megasquirt. I can also run much bigger spark plug gaps. The system is way more precise then running a distributor. I will be adding an MSD DIS-4 Soon.