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Can't seem to figure this problem out. Freshly rebuilt engine from reputable builder in my area. All new ignition components (MSD 6AL, Billet Dizzy, Ford Racing Plug Wires, Pertronix Distributor). Motor seems to run smooth, but has substantially less power than it should. All plugs look great except #1 cylinder. Plug is black sooty/fouled. NOT oily or wet. Compression is good on all cylinders, including #1 (approx. 165 psi). Ohm reading on all plug wires is good. Cylinder is getting spark.

Other problem is that timing mark bounces between 4 and 6 degrees at all engine RPM's (when trying to set at 36, have to settle for bouncing between 33 and 38 degrees). MSD suggested interference with magnetic pickup wire from box to dizzy. Am running MSD's shielded wire, separated from other wires. Closest it comes to the wiring harness is about 4". Am also using a non-digital, non-dial back timing light as suggested by MSD.

Perhaps these problems are completely unrelated, but does anyone have any input on either one? Thanks for any help, I'm pulling my hair out with this.
 

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Sounds like that cylinder isn't firing, try another plug wire and if no luck get a new plug first before ya suspect the worse, also are that cylinders valves adjusted correctly?
 

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Sounds like the plug wire is grounding somehow and not firing.

Isolate the wire, check it with a magnifying glass for any cracks or moisture, same with the tower. Check the entire path to make sure it does not cross any other wires at any point. Do a resistance check on the wire with an ohmmeter to see if something is kitty-wompus v. the other wires. Check the wire with a good 'known' replacement wire and see if you still have the problem after you check all the above.

Good luck!

BOB
 

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6AL boxes will cause an erratic timing reading because under 3000 rpm, the plug is firing multiple times. That would be the M in MSD.

Sounds like a misfire on that cylinder or maybe an intake vacuum leak pulling oil mist in from the crankcase. My guess would be the misfire.
 

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I've never had a timing light mis-read with my MSD, and I've used anything from a cheapie Actron to a quality craftsman.

Sounds like the wire's got something funky going on.
 

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Few questions... Is the MSD connected directly to the Battery? It shoud be. The coil should still be connected the normal ( Stock) way through the facory ignition wire ( Positive coil connection) this wire should also have a resistor on it.
 

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Check your timing on another wire to see if its stable. If it is, its somewhere in that single cyl circuit

If it still does it, check to make sure your advance springs arent broken or loose
 

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I have the same problem. A couple things that I know are causing it on mine are worn dist. gear (bronze gear is a few years old), the inductive clamp on the timing light, and running the timing light wires anywhere near other igntion wires, coil, distributor, or high load wiring.

I am in the process of replacing the gear as we speak. As far as jumping around 2 degrees, I don't worry too much with it...rev it to 1800 (just off idle), set it at 32-34 and forget it. Runs fine that way.

At one time I ran a gear drive....thinking that would solve the erratic readings. nope. Same. Nothing changed other than the ET and MPH (lost ET and mph) so the chain went back on and I got my ET back.
 
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