Does anyone know harmon collins firing order?

It is the engine design, not the distributor that determines firing order, isn't it? Inquiring minds want to know.
 
It is the engine firing order that matters, but I think your question is where on the cap do the wires go. While I'm not fortunate enough to have a Harmon Collins, I do know if you look at the rotor it will tell you the phase for the plug wires. If it's split like a vee then line up the leading one with a wire post and then count backward to the next firing one based on the rotor shape. Typically it's a 180 rotor with both ends firing 180' from each other to the same cylinder. That's an easier one as it's just puting plug wires 180 from each other. Post a picture it'll get a better result.

Tim
 
Dual point or dual coil? The former is the same as a single point. The latter as shown in the attached images (7-5-6-2-4-3-1-8 starting from top right).
 

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The firing order on the caps is different on the H&C. The engine firing order remains the same. Now if I can just figure which hole in the cap fires which cylinder I will be fine.
 
The rotor contacts are 180 degrees appart but the points don't open at the same time. The HC instructions show the No.5 points open 45 degrees lag after the No.1 points so it would fire at the next terminal that comes in order from the 180 degree mark of the last terminal fired. If you study which points open at which terminal its pointing to you can come up with an order of rotation then transpose the engine firing order to the new order of rotation and you would have the proper plug wire locations for the standard type cap. Its definitely confusing when compared to a regular single coil system but a person should be able to figure out the order of system function since each coil would have to fire every other terminal post in order to cover all eight in one rotation of the distributor.

You could put the No.1 cylinder plug wire where ever you wanted to start out with but you would have to locate it for best reach for each spark plug location around the cap.
 
My head hurts, but as RW says correlate point break and rotor tip position.
Ford shaft and cam are coupled direct to cam, so #1 doesn't need to be rethought, the 2 rotor tips alternate, it can be figured out with a bit of coffee and some calm reflection. I would figure it with distributor off engine for ease of manipulation ans vision, then get a test plug or test neon on a piece of secondary wire and test my terminal choices by spotting the actual spark while slowly rotating engine before I actually hookedumup.
 
I did a couple of checks with No.1 plug wire in different positions and it seems to me that if you put the #1 on the bottom of the passenger side that all of the right bank or passenger side cylinders would be on the right and all the left or driver side cylinders would be on the left side of the cap. I wished I had one to look at to be sure. This is assuming the thing rotates clockwise looking at it from the front. If it turns anti-clockwise then I'm bass akwards in my thinking.

Now if the rotorbug is keyed to a specific spot with the distributor cam & camshaft with no adjustment that is possible and the No.1 cylinder is at 2 degrees BTDC, then thats where the No.1 position has to be then clock it from there.

Taking another look at the cap pictured in post 4, It looks correct for anti-clockwise rotation if the points cam is fixed. That cap is from top to bottom 8, 1, 3, 4 on pax side and 7, 5, 6, 2 from top to bottom on the driver side which is probably correct. Especially so if the No.1 position is fixed.
 
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rotorwrench said:
I did a couple of checks with No.1 plug wire in different positions and it seems to me that if you put the #1 on the bottom of the passenger side that all of the right bank or passenger side cylinders would be on the right and all the left or driver side cylinders would be on the left side of the cap. I wished I had one to look at to be sure. This is assuming the thing rotates clockwise looking at it from the front. If it turns anti-clockwise then I'm bass akwards in my thinking.

Now if the rotorbug is keyed to a specific spot with the distributor cam & camshaft with no adjustment that is possible and the No.1 cylinder is at 2 degrees BTDC, then thats where the No.1 position has to be then clock it from there.

Taking another look at the cap pictured in post 4, It looks correct for anti-clockwise rotation if the points cam is fixed. That cap is from top to bottom 8, 1, 3, 4 on pax side and 7, 5, 6, 2 from top to bottom on the driver side which is probably correct. Especially so if the No.1 position is fixed.
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Good job , i think you got it !!! Rotation is counter clock wise and the rotor is keyed to a specific spot as well. I have two in the shop for a rebuild and will post as soon as i get to them........
 
Shaft is keyed direct to cam and runs to rotor so no choilces there! Thus you can find #1 choice on distrib just by setting #1 cylinder to firing postion and putting on distrib--it will be pointing to #1
 
An old timer gave the firing order on Saturday and Sunday morning it was running. 7, 5, 6, 2, on drivers side and 8, 1, 3, 4 on passenger side did it. :D
 
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