Correct vacuum advance

[Curt C.]

I am trying to determine the correct vacuum advance for my 1966 427/390. There seems to be conflicting data. Can anyone help? Thanks, as always.

[Duke W.]

Re: Correct vacuum advance

What data do you have, so far?

Duke

[Joe L.]

Re: Correct vacuum advance

I am trying to determine the correct vacuum advance for my 1966 427/390. There seems to be conflicting data. Can anyone help? Thanks, as always.

Curt-----


The original vacuum advance, with or without TI, was GM #1115355. This control is long-since GM-discontinued. It is available in reproduction for about 40 bucks but I've been told the calibration is not always right.

For a replacement vacuum control, use GM #88924983, aka Delco D1310C. This control is marked "B20". You can also get the exact same part under NAPA/Echlin VC-1765. These controls are very similar to the originals except for the "numbers" and other minor "nuances".