Multiport Sequential Electronic Fuel Injection Retrofit for V8 Engine

This project builds off of my previous experience of updating carbureted Ford engines with late-model Ford fuel injection systems.  The vehicle used for this build was a 1977 International Harvester Scout II with an International Harvester 345 V8 gasoline powered engine. 

The use of an orphan vehicle (ie made by a manufacture who no longer engages in the manufacturing of light duty vehicles) presented added complication in that modern parts are not readily available.  Of particular importance in fuel injection control is being able to find a distributor that allows for electronic control of the ignition timing.  Although IH did do some development work in the early 70's on both mechanical and electronic fuel injection nothing was ever released for production.

Since my previous experience had been with the Ford EEC-IV system modified with a Tweecer from STKR.  I found the EEC-IV with Mass-air sensor adaptable enough to make the changes I needed but simple enough to not require excessive hours of tuning.  I also needed the real time data logging of the RT model.
http://www.tweecer.com


To overcome the distributor hurdle I investigated using a distributorless ignition system (EDIS) found on the later 4.6L engines.  Luckily the EEC-IV was able to adapt to this.  It required installing a crank speed sensor, which I installed spaced out from the front of the damper.  Later I saw where someone had mounted a similar sized toothed gear behind the damper which was a prettier solution, although at the time I didn't have access to the machining tools needed to do such a thing.  Since the oil pump was driven by the bottom of the distributor I had to leave the bottom half of the distributor installed.  The coil packs were mounted on top where the cap originally was.

The intake also presented a problem.  The cast iron intake obviously did not include provisions for mounting  modern fuel injectors.  It did conveniently have extra material on top of each intake runner that I assume was part of the casting process.  These were leveled off with a grinder and then drilled for each injector.  Matching fuel rails were made and mounted to where the carburetor previously mounted.  An aluminum elbow was then mounted in place of the carburetor which was connected to the throttle and MAF sensor.

Getting it to run was fairly easy.  It would run with the base Mustang calibration although not well as there is a significant difference between the higher revving Ford 5.0 HO and the slower more torque oriented IH 345.  Once the MAF calibration was adjusted to account for the heavily modified intake system, it ran pretty well.  Much better than I've ever gotten a carburetored 345 to run.  Fuel mileage was in the mid teens, which isn't great, but you can only do so much with such a heavy block of a vehicle.