Distributor Orientation Question

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JPWally

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1969 Mach 1
1973 Mach 1
1972 Sprint Fastback
Just finishing up the final touches on a 351C (M code converted to 4bbl) rebuild in a 1973 Mustang. The engine started nicely and I have run it in for 30 minutes or so. When I went to adjust the initial timing(vacuum line disconnected and plugged), the distributor vacuum pot is hitting the top radiator hose before I could even get to 10 degrees BTDC. I am looking for more advancement on the timing. What is the correct way to reorient the distributor body for good clearance between the A/C bracket and the upper radiator hose? Rotate the wires? It is an OEM distributor with a Pertronix ignitor.
Thank you !
 

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Mark the number one plug location on the metal part of the distributor below cap. Bring number one cylinder to tdc. Pull the distributor out and rotate it in your case counterclockwise away from radiator hose. Now rotate the rotor so it will align with the number one plug wire mark you made and then put the distributor back in. You may have to play with it a little since you will need to get the oil pump shaft aligned to go back in. Should give you enough room to rotate the distributor then to get your timing set.
 
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What is the best initial timing you get in the current position?
You have the option of moving each wire one position clockwise. If you do this and do not turn the distributor it will add 22.5 degrees of advance (crank) to the initial timing.

The ignition doesn't care where the clips are on the distributor.

If you decide to lift the distributor do as explained above. BE CAREFUL because you can pull the oil shaft up and out of the oil pump, it doesn't happen often but it sucks when it does!

Raise the distributor housing slowly. When the rotor stops turning it has disengaged from the cam gear. This is when you want to try to rotate the rotor, no need to lift it any further unless it won't turn in which case, raise the housing a bit more until it does.
 
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JPWally

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Detroit, Michigan
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1969 Grande'
1969 Mach 1
1973 Mach 1
1972 Sprint Fastback
Thank you gents for the quick responses. My best initial timing I can achieve by bumping into the upper rad hose is about 10 degrees BTDC. After rotating the plug wires one position clockwise, it is too much advancement (and now bumping into the A/C bracket). After a couple of tries using Kilgon's and Don's suggestion I still cannot reorient the distributor body due to bumping into the A/C bracket upon re-stabbing..... If these are my only options for obtaining more distributor clearance, I will keep trying with diligence...........
 

steves73

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Just finishing up the final touches on a 351C (M code converted to 4bbl) rebuild in a 1973 Mustang. The engine started nicely and I have run it in for 30 minutes or so. When I went to adjust the initial timing(vacuum line disconnected and plugged), the distributor vacuum pot is hitting the top radiator hose before I could even get to 10 degrees BTDC. I am looking for more advancement on the timing. What is the correct way to reorient the distributor body for good clearance between the A/C bracket and the upper radiator hose? Rotate the wires? It is an OEM distributor with a Pertronix ignitor.
Thank you !
Mine looks a little retarded, but any more advance causes difficult starting. Maybe a smaller diaphragm housing would help you?20220610_120300.jpg
 
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Thank you gents for the quick responses. My best initial timing I can achieve by bumping into the upper rad hose is about 10 degrees BTDC. After rotating the plug wires one position clockwise, it is too much advancement (and now bumping into the A/C bracket). After a couple of tries using Kilgon's and Don's suggestion I still cannot reorient the distributor body due to bumping into the A/C bracket upon re-stabbing..... If these are my only options for obtaining more distributor clearance, I will keep trying with diligence...........
You made need an oil pump primer tool to get the pump turned enough where the distributor will drop down. This will allow you to index the pump a little at a time to get the cam gear moved one or two teeth needed to get the distributor back in.

1654888623652.png
You can get these just about anywhere online and at some of your better auto stores. Cost around $10 to $20 depending where you get it at.
 

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