66 427/390 Distributor

[Richard S.]

The distributor currently in my 66 is a 69 distributor. The numbers on the tag read: 1111926, dated 9K5. This number indicates correct distributor for a 69 427, 390 and 400 horse Corvette. Before I do any more work with it are the specs also correct for my 66 390 car ( should be 1111141 )or should I find a correct 66 model?
Thanks.

[Joe L.]

Re: 66 427/390 Distributor

Rick-----

The distributor may work ok as-is. However, the specifications are different between the 2 units. As always, though, the only differences between Corvette tach drive distributors relates to the mechanical and vacuum advance characteristics---everything else is virtually the same between all.

To convert the distributor to the exact 1111141 configuration, you will need to have an experienced distributor repair shop convert the mechanical advance to the 1111141's specs and you'll need to replace the vacuum advance control with a GM #1115355. Unfortunately, the latter piece is GM-discontinued, but it may be available in reproduction.

If you could obtain the following parts, you could convert the mechanical advance yourself:

mainshaft with auto cam-----GM #1966992

weights (2)-----------------GM #1881371

springs (2)-----------------GM #1911484

I don't think that you'll be able to find these pieces, though. A distributor shop with a Sun machine (or equivalent) can convert the mechanical advance to the 1111141 specs without having these exact parts available.

[Duke W.]

Re: 66 427/390 Distributor

A '69 model distributor would be set up more for emissions than performance and economy, so you would be well advised to "back date" it to closer to '66 specification. This could involve as little as swapping the vacuum can and a different set of centrifugal springs.

Duke