Detail Question on Plug wire location for Hemi DP Prestolite

Reviewing a ton of pictures on the Web for Stock 426 hemi cars I see a lot of different orientations of the distributor and wire location on the cap.

If you follow the Manual procedure for timing the Distributor you do wind up with the Prestolite Vacuum chamber pinched between intake manifold and fuel lines.

I have seen distributor VC behind fuel lines, and in front. I have seen Plug 1 wire at various locations, several cap slots different.

This is not an actual timing issue. The distributor only moves 5-8 degrees to get 10-16 degrees initial timing.

The manual does not give you a diagram for wire location on the cap. Just the firing order.

Part of the issue is that there are many variation to Prestolite DP shaft clocking (Orientation of the engagement slot on shaft), different Cam stop flat orientation which drives what direction the rotor points.

With many of these distributors being rebuilt or purchased as rebuilt back in the day you may not have original internal parts and the clocking is off.

So does anyone know what the orientation was from the Factory for the 68/69 hemi cars?
Looking at generic Motor Manuals they show that the 1 and 8 plug wire should straddle the fwd cap clip on Big Block engine, but no distinction made between Chrysler or Prestolite distributors. Is this the correct wire location for hemi prestolite dual point for 68/69 cars?

Maybe I am missing it but what are you trying to accomplish?

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Regardless of new/rebuilt, the orientation of the main shaft will be the same. IOW, the cam plate and the rotor index off of the main shaft.

I am trying to determine correct location for #1 wire on the cap in reference to the forward position.

John I can show you prestolite shafts with different clockings on the tip as referenced to the weight assembly. Both big block DP shafts.

I can also show you Cam stops with the Flat for the rotor clocked at different angles. I know SP are different, but some of these are DP with different letter stamps. Not just a different slot length, but a different flat location. So a rebuilder that put different cam stop or shaft in for some reason could get the rotor pointing in a different direction forcing a wiring move, or setting distributor gear in a different position from the manual standard. Early Prestolite SP distributors used a similar cam stop because they used the same rotor and cap as the DP.

I agree you think it would be the same, but I have seen # 1 wire in all different locations on OEM looking Hemi cars with Prestolite distributors.

I did get a good answer on B body forum.

Cam installed correctly and intermediate shaft installed correctly, #1 at bottom 6 o’clock.

Thank you, just to be clear 6 oclock is toward passenger side of the motor and center of motor is 12(where Vacuum chamber points)?

FWIW, here's a pic of a pre-'70 with the VC pointing to the front under the fuel lines. Does look like #1 is at 6 o'clock.

Not exactly sure what would be factory correct as far as plug wire orientation but I seem to recall an "old timer" telling me to offset the wire terminals by one or possibly two positions to make the Hemi wires lay better across the valve covers. My #1 is one over (CW) from the 6 o'clock. Subtle, but it helps.

I always had my #1 two holes to the left of the front cap hold down clip as you’re looking from the front. At top dead center with your timing mark on 0, the slot in top of the oil pump drive gear is supposed to be parallel to the centerline of the crankshaft. My #1 plug wire for my old Hemi and my 440-6 motors was always in the cap terminal closest to the front of the valve cover but I think it was just two holes towards the passenger side of the cap hold down clip?

To keep the vacuum advance in the center this is where I put number one

Nice garage shot Jerry - looks like the old Woodward Garage.