I am working on a 66 F100 that has a 75 300 engine (not running) installed in it. Should I use the original (still installed) 75 HEI distributor with a 3 wire connector or switch to a point type single wire distributor that the truck is originally set up for? If I do switch, what would be a good replacement distributor? Thank you!
I'd use the points distributor. Are you aware of how Ford Duraspark ignition works? and the parts required to make it function? it's not an HEI distributor, it requires an amplifier module, and a specific coil, and they changed over the years, so you have to match parts appropriately. Wiring them properly can be confusing.
Can use the duraspark dist and pickup with an HEI module. If the distributor currently has the large cap, male terminals, with adapter, these can be removed and the small cap female terminals for the older points can be installed for a look.
The theory is that with the electronic ignition, you never have to change the points or condenser again. A correct operating electronic Ignition could function without an issue for 100K miles, you only had to change the plugs, cap, rotor, and plug wires. The timing & dwell didn't change. Ford did change their electronic ignition systems every year for the first 3-4 years they produced them. I believe they were searching for the best set up. As a mechanic, back then, you had to know the build date of the car/truck you were working on to get the correct electronic ignition parts for the correct system. Around 1978 I got out of the auto mechanic trade for several years, so I don't know if Ford ever figured out a way to make the multiple systems thing work out. My personal collection was only Chrysler stuff, so I worked on figuring their stuff out and didn't follow the other companies.
The large cap Duraspark 2 didn’t arrive until 1977. Cost a bunch of money to convert or track parts to. I’d use either what you have, Duraspark 1? or convert to points.
I went to a boneyard and took the entire Duraspark system off a 78 or so f 150. Went back to my 56 w/300 6 and put it on. Went on Ford Truck Enthusiasts site and started a big argument amongst them about how to hook up properly. Anyway it's been on my 56 F100 for 13,000 miles.
This ^^^^ will work great with a HEI module , but not with a TFI module. The HEI and TFI are basically the same thing but the HEI has the proper input for a magnetic pickup distributor @Bob Bagley The HEI Module has 4 pins labeled W, G, B, and C. G Pins W and G go to the magnetic pickup. On a Duraspark distributor the purple wire runs to pin G and the orange wire goes to pin W. Run the black wire from the Duraspark distributor to one of the mounting screws on the module [Ground] Pin B on the HEI module goes to the positive coil lead [which gets 12v from the ignition switch ] and pin C goes to the negative coil lead [and Tach signal] The HEI module needs to be mounted onto Aluminium with proper heatsink paste [it can be mounted remotely] This will make a cheap electronic ignition ,But if you're wanting to use a cheap "Aliexpress" module then don't bother [ Just use a MSD 6 instead] Genuine "junkyard" GM modules are more reliable than new Chinesium modules
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