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Distributor wires off by two indexes. Problem?

mrmolding

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So I decided I’d change the cap, rotor, and wires on my 383 70 RR and realized that they were longer wires than normal. After looking around I figured out that they are the correct firing order but just starts two indexes on the cap from normal.
The car was upgraded at some point to electronic ignition and actually runs and starts very well.
I have not checked timing or tdc on cylinder 1 yet but wonder if during the rebuild something got out of whack.
Thoughts?

32EF786F-1244-4FBE-B894-1636EE63E3DB.jpeg
 
Oil pump drive shaft/gear is probably off by a tooth, so they made up for it on the cap. Otherwise the vacuum can would be way forward (or maybe it was too far back). That said, pending which way the wires are two off you may be able to rotate the distributor enough to correct the wiring positions without moving the pump shaft gear location.
 
If you want to, you can re-index the distributor by removing it, using a long flat screwdriver to back out the intermediate shaft and shifting it over a tooth or two.
 
If you want to, you can re-index the distributor by removing it, using a long flat screwdriver to back out the intermediate shaft and shifting it over a tooth or two.
Thanks! I guess I’m wondering if I need to worry about this immediately or if it can wait. The motor was rebuilt in 2012 and only has about 5k on it. It baffles me that if this was an issue that it was left this way. I’ve had the car for about 3 months and digging into it. Thanks again!
 
Oil pump drive shaft/gear is probably off by a tooth, so they made up for it on the cap. Otherwise the vacuum can would be way forward (or maybe it was too far back). That said, pending which way the wires are two off you may be able to rotate the distributor enough to correct the wiring positions without moving the pump shaft gear location.
Makes sense! It is two indexes counter clockwise. Thanks!
 
It doesn't hurt anything to run it as is... Only person that would ever realize it is some sick individual that spends wayyyy to much time looking instead of driving...
 
It doesn't hurt anything to run it as is... Only person that would ever realize it is some sick individual that spends wayyyy to much time looking instead of driving...
That made me break out laughing!!! I guess I need to enjoy the car and pretend that it’s in great shape! Thanks for that!
 
I prefer and always have set the gear per the manual. That way no one has to second guess. Seen many guys like this post started had a car that ran well but decided a new cap, rotor and wires were in order. Pulled them all off not noting or thinking of orientation. Then installed the new and followed the manual or the 1 marked on some caps then the party started. Being older and old school I am set in that mind set to do it right. Plus I am so used to pulling the distributor for a proper set up and tune.
 
I prefer and always have set the gear per the manual. That way no one has to second guess. Seen many guys like this post started had a car that ran well but decided a new cap, rotor and wires were in order. Pulled them all off not noting or thinking of orientation. Then installed the new and followed the manual or the 1 marked on some caps then the party started. Being older and old school I am set in that mind set to do it right. Plus I am so used to pulling the distributor for a proper set up and tune.
This is my thinking too. Since you found the issue, it only takes a few minutes to correct it.
 
This is my thinking too. Since you found the issue, it only takes a few minutes to correct it.

I remember doing it years ago and I’m sure it will come back to me. I converted a 68 Gtx and 69 Rr to electronic ignition using a direct connection kit if memory serves me. I think it’s more of the frustration with buying a car that seems to be really sorted out with a rebuilt motor but you find odd things like this. So naturally I keep digging!
 
Pull number 1 plug. Bump it over until it is coming up on the compression stroke. Align the damper to the tdc mark on the timing tab. Pull your distributor and rotate the intermediate gear until it looks like this. Drop the distributor back in with the rotor pointing to the correct number one terminal. Put the wires on and set your timing.

bigblock tdc.jpg
 
the factory indexing of the oil pump shaft doesn't work for MP/Mallory distributor... just in case someone here has it. The rotor on the MP/Mallory dist is around 80°-90° off from the stock dist, SOOOOOO, if you want to meet number one marked on cap will need to index the oil pump shaft accordingly to the MP/Mallory index.

BTDT
 
Here is the rest of the FSM section. One problem with the distributor out of phase is the location of the vacuum advance on the distributor. It was designed to have enough clearance between the other items on the manifold to allow full adjustment movement.
 

Attachments

  • 383-440 DISTRIBUTOR OIL PUMP DRIVE INSTALL.pdf
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Great help everyone! Thanks again!
 
Even though you can run it as is, it's good to know the why and how....
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