I have the subject distributor and I am unable to correlate the vacuum advance number stamped into the unit, A7, with the information found for the distributor on 442.com per the following.

1111977 1973427 455-4V-HC A-body MT w/W30 [TS]
1111977 [specs: VA begin @10-13 inHg, 4.2-7.3 deg @16 inHg.
Mech 0.4-2.4@ 500RPM, 8-10 @900, 10-12 @2000]

Backround on the unit...I purchased it from the Olds Employee Salvage Store in 1970.

Much appreciated if someone knows and can enlighten me as to what the
A7 designation means.

Dave

 

Scroll down the link and there are part numbers and specs. Its the VC1755 can.
http://www.lbfun.com/warehouse/tech_...ance_Specs.pdf

 

I am not sure what the A7 means, but an original vacuum advance would have stamped in the same area "MS 427-16" the 16 referring to the vacuum. I believe the A7 vacuum advance pot is a modern generic advance. It is not correct for the era of the distributor.

 

Just an FYI,
You likely know but that is a valuable distributor. I know a guy that would be interested in it if you decide to sell it. I can hook you up with him if you decide to let it go.

 

Just to show what RocketDevo exactly described.

Don W

 

I edited in the forgotten link in post #2

 

Thank you (and others) for your responses. As I indicated in my inquiry, I purchased the distributor from the Olds Employee Salvage Store. I am now thinking that at some point during final assembly of the engine it was intended for, or during engine testing, the discrepancy was discovered, (the distributor was found to be incorrect for the application) and it was subsequently taken out of production and sent to Salvage. Just my theory.

I have been in the process of trying to locate a suitable W-30 to restore, but have lost interest so I am having thoughts of selling it. Not sure how to price it and I have not made the decision to pull the trigger just yet.