Modifying the Holley HyperSpark distributor 565-315 (made for the "small block") to work with a "big block " Ford 240 six or 300 six

I am reading this as, the module serving as a passive interface. It will have no duty as an ignition control module anymore?
Yes, as far as I can tell, the PIP signal from the module is a pass-through of the hall-effect sensor. So the largest function of the module is to close the big hole in the side of the distributor. Also, as far as I can tell, the hall-effect sensor in the Holley and the Ford are identical - at least the molded plastic is identical.

So it appears that Holley basically copied Ford's vane and sensor design (not that there is anything wrong with that).

Yes it will be a passive interface and the Sniper 1100 takes on the ignition timing duty.
It can still be used as a TFI ignition coil driver but then you are back to the heat issue that caused Ford to move the unit remote from the distributor.

Ah, that explains why the module has a big aluminum plate as its back, which mates with thermal paste to the distributor housing. I put it back the same way with some thermal paste I had on hand. I do not know what they were thinking, trying to cool electronics by thermally coupling them to a hot motor :rolleyes:. Well, maybe I have a hint . . . the whole thing looks like someone trying to incrementally push advanced electronics into a then 40-year-old mechanical design against huge institutional resistance to change. Good for me in this case :)

I did not mention above, but I used some high temp RTV to secure the black plastic hall-effect sensor assembly to the shaft so it is completely immobilized. The Ford design has an arm to lock it in place, but it still could wiggle slightly. Not anymore.

I will say that the Ford distributor has amazing mechanical design. Oil passages inside the shaft, even a special washer with an oil passage. There is a spiral track on the outside of the shaft to manage oil distribution, pure end-stage mechanical design evolution.

Another -- possibly minor -- thing about the Ford design is that the rotor has a wide arc at its tip. This design should allow the rotor to be close to the points in the cap for a longer period, allowing more freedom for the ECU to change the spark timing. The Holley rotor has a narrow tip.

I will be away from testing this distributor for a bit, I need to make a throttle cable, get the throttle body mounted, finish the fuel lines, and do all the wiring. Plus I'll be away for a few days so it may be a while before I update. I'll post progress on all that other stuff over on the My 1969 F100 Big Block Six 240 Holley Sniper EFI Train Wreck Project thread.
 
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I believe that the distributor is supplied power from some other component in the Holley system.
The distributor gets its power from the ignition adapter cable that is supplied with it and not from some other component in the Holley system.
The cable has a two and a three pin connector with a pink wire that goes to a switched power source controlled by the ignition switch.
The Holley Sniper gets its power from the same point.
The two wire connector only supplies trigger signal form the Hyper distributor to the Sniper.

The Sniper triggers on the signal edge that goes from zero to supply voltage the same as a set of points would do.
If the two wires were reversed the Sniper would trigger on the other edge and the ignition timing would be off for one of the six cylinders due to the cylinder #1 ID spacing.
The rotor phasing will be off also.
If you make up a new cable for the Ford distributor make sure the polarity it correct.

Once the engine is running I would check the trimming on all six cylinders just to be sure.
Once the distributor timed with a timing light you will need to check the rotor phasing.
 
I did not mention above, but I used some high temp RTV to secure the black plastic hall-effect sensor assembly to the shaft so it is completely immobilized. The Ford design has an arm to lock it in place, but it still could wiggle slightly. Not anymore

Another -- possibly minor -- thing about the Ford design is that the rotor has a wide arc at its tip. This design should allow the rotor to be close to the points in the cap for a longer period, allowing more freedom for the ECU to change the spark timing. The Holley rotor has a narrow tip.
Glad you were able to secure the sensor to the housing. On the earlier pics of the distributor, the rubber exterior cover under the single-screw hold down was gapped at the bottom, and you had wiggle. My (untouched) factory distributor, the sensor plated is immovable, and the rubber cover is flush to the housing on all sides. Shouldn't wiggle, someone else didn't reassemble it carefully. Good catch.

I am surprised the Holley has a narrow rotor contact area, considering all timing advance is dependent on that contact patch.
 
Please explain.
The relationship rotor-to-cap is fixed, locked in place on the computer timing units, unlike cent. advance where the rotor moves forward relative to the dist shaft and cap as the timing advances.
A wide rotor contact end at the cap post is necessary, since as timing advances, the rotor is still arriving at the cap post at the same time as base timing. If there's not enough leading edge on the rotor end, the advanced timing spark won't transfer to the cap.
 
Great information.

One more favor please for the sake of adding to the information base.
What is the measurement from the bottom of the distributor hold down collar to the bottom of the gear on the 88 distributor?
Thanks

I just added this thread to the information stickies in the "240-300 Big Block Six Performance" section
 
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. . . What is the measurement from the bottom of the distributor hold down collar to the bottom of the gear on the 88 distributor? . . .

Ummmm . . . I'll have to pull it out and then do the static timing again. Give me a bit.

. . . I just added this thread to the information stickies in the "240-300 Big Block Six Performance" section

That might be a bit premature . . . I do not know that any of this works at this point :-(
 
The Holley has that same arrangement - one vane is more narrow. I'll get some more photos and measurements tomorrow.

One thing I do not like about the Ford distributor is that the mechanism that could be used for mechanical advance (but is locked out) makes the mounting of the hall effect sensor a little wobbly compared to the Holley which is rock solid.

I'll poke around tomorrow and formulate a plan. I'll probably end up with three distributors, none of which work.
Looking at the hall effect sensors of the Holley and the Ford:

View attachment 11020

Except for the connections, the sensors are identical. Also, I verified that the Holley uses a hall effect sensor.

I got the Ford distributor completely disassembled, cleaned, lubed and reassembled:

View attachment 11021

I got it installed, and did static timing of 12° (from @djstucker's video, IIRC) on what I think is the correct vane inside the distributor. I guess I'll see if it was correct.

As far as the diode, I will have to see how the Holley wiring goes - - I believe that the distributor is supplied power from some other component in the Holley system.
DO YOU HAVE MORE INFORMATION ON HOW THIS WORKED WITH THE SNIPER
 
DO YOU HAVE MORE INFORMATION ON HOW THIS WORKED WITH THE SNIPER
 
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