Proper wire location for MSD Ignition

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Nov 23, 2021
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Ok guys. I have a 1970 SS Chevelle with the original (rebuilt to stock) 396/350 hp motor. The ignition has been converted to an MSD 85551 system (distributor and box) with a MSD 84335 cap and rotor. As my old sparkplug wires got burnt by my headman headers, I am in the process of making new custom wires to replace the old.

Question, a helper pulled my old wires off without marking them but did mark the cap where the #2 wire supposedly went which is on the driver’s side just in front of the cap hold down screw. In looking at my old Chilton’s manual for year and model it shows the number #2 terminal on the cap is behind the cap screw not in front of. Any idea which would be the proper #2 location? I do not wish to cut and replace the wires only to find I am 1 digit off and most likely cause a misfire.
 
Set the engine to #1 TDC. Where the rotor points is #1 and then just go with the fireing order from there. You can move anything around to make room for vacuum can etc.
 
Set the engine to #1 TDC. Where the rotor points is #1 and then just go with the fireing order from there. You can move anything around to make room for vacuum can etc.
I would add that when the mark on the harmonic balancer is lined up with the 0 or TDC mark on the scale on the block, the rotor should point at either the #1 or the #6 terminal on the distributor cap.

If it's pointing at #1, great, go from there. If it's pointing at #6, crank the harmonic balancer over one complete revolution, and recheck. The rotor should then point to the #1 terminal.

The other way is to remove the #1 spark plug and ensure that the piston is at TDC (rather than BDC) when the rotor points to #1. If not, turn the crank another revolution.

Once you've determined where #1 is, go clockwise, following the firing order - 1-8-4-3-6-5-7-2.
 
As others have said, verify TDC with cylinder #1 on compression stroke. You may need to restab the distrubuter to achieve factory position.
 
Cap was put in exactly as old one was removed. Battery is out of car at the moment which is why I was referencing the cap/wire location. Only believe one off, if at all.
 
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You don't need the battery. Turn the crank using a breaker bar on the bolt until the timing mark on the balancer is under 0 on the pointer.

Then take the cap off to confirm the rotor is pointed at 1 (5 o clock as you stand in front of the car) or 6 (11 o clock). It doesn't matter which in terms of putting the wires on. If that is the case the distributor is likely properly installed (though it could be exactly 180 degrees out). If it doesn't line up you should re-time the distributor so the wires can be installed in stock locations to avoid confusion later.
 
View attachment 111130
You don't need the battery. Turn the crank using a breaker bar on the bolt until the timing mark on the balancer is under 0 on the pointer.

Then take the cap off to confirm the rotor is pointed at 1 (5 o clock as you stand in front of the car) or 6 (11 o clock). It doesn't matter which in terms of putting the wires on. If that is the case the distributor is likely properly installed (though it could be exactly 180 degrees out). If it doesn't line up you should re-time the distributor so the wires can be installed in stock locations to avoid confusion later.
 
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View attachment 111130
You don't need the battery. Turn the crank using a breaker bar on the bolt until the timing mark on the balancer is under 0 on the pointer.

Then take the cap off to confirm the rotor is pointed at 1 (5 o clock as you stand in front of the car) or 6 (11 o clock). It doesn't matter which in terms of putting the wires on. If that is the case the distributor is likely properly installed (though it could be exactly 180 degrees out). If it doesn't line up you should re-time the distributor so the wires can be installed in stock locations to avoid confusion later.
Gonna give this a try. Too bad #2 is so close!! Thanks
 
If it's pointing at #1, great, go from there. If it's pointing at #6, crank the harmonic balancer over one complete revolution, and recheck. The rotor should then point to the #1 terminal.
Last week I replaced the intake gaskets on my farm truck ('78 c10). I turned the engine manually to line up the balancer mark and the rotor was pointed at 6. Well, 6 it is! When I was done, I ran the wires starting from 6 and it fired right up.
 
Last week I replaced the intake gaskets on my farm truck ('78 c10). I turned the engine manually to line up the balancer mark and the rotor was pointed at 6. Well, 6 it is! When I was done, I ran the wires starting from 6 and it fired right up.
For sure! Just start at 6, and going clockwise you could do 5, 7, 2, 1, 8, 4, and 3.
 
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