Correct '66 Vacuum Advance

[Ian S.]

Hello,

My '66 is a 327/300 hp with A/C. I have a vacuum advance canister that came off of the engine originally with the markings MS 355 15. Is that canister correct for the car and are the markings correct for judging?

Thanks,

Ian

[William C.]

Re: Correct '66 Vacuum Advance

what is the part number on your distributor? If a 1111153, it should have the 355 vacuum can originally.

[Duke W.]

Re: Correct '66 Vacuum Advance

Make sure it's functional, and remember that the whole VAC is worth 3 points - 2 for originality and 1 for condition, so if it needs to be replaced with a NAPA VC1765 or equivalent (stamped B20 or B26) OE replacement, you should only loose one point.

A correctly calibrated and functioning VAC is critical to good engine operation and fuel economy.

Duke

[Ian S.]

Re: Correct '66 Vacuum Advance

Thanks for the help Bill and Duke. The distributor is a 1111153. When I took the original Vacuum canister off the car it was working but didn't look so good. I've been able to clean it up and I'll get it checked to see that it works properly. I agree I'd rather have a correctly functioning one if it doesn't check out. The repo from Long Island was not calibrated correctly so the car currently has the NAPA replacement and that works great.

Thanks again,

Ian

[Gene M.]

Re: Correct '66 Vacuum Advance

I think you will find the NAPA VC1765 or equivalent (stamped B20 or B26) OE replacement, would be a full deduction 3 points. The can stamping configuration is totally different and it would not qualify as a GM replacement.

[Duke W.]

Re: Correct '66 Vacuum Advance

That would be unduly harsh - the same deduction as if the VAC was completely missing! The geometry of most of these replacement VACs made by Standard Motor Products (including those sold in "Delco" boxes) is the same as the long gone OE Delco parts, so I consider most SMP VACs to be "service replacement parts". The only telltale sign is the stamped data.

A "service replacement part" is anything cataloged by GM, and all vintage VACs sold by GMPD and Delco are made by SMP and carry the same stamped ID as the same specification VAC sold by all other major brands. (Refer to Section 4 subsections 6 and 7 of the Judging Reference Guide.)

If if were my car being judged and a full deduction was taken for a SMP VAC I would protest to the event judging chairman.

Duke

[John H.]

Re: Correct '66 Vacuum Advance

The VC-1810 can (stamped B28) comes from GM in a GM/AC Delco box, with GM part number 88924985 and AC Delco part number D1312C on it; I'd say that qualifies it as a "GM replacement" part. I bought several of them three months ago.

[Duke W.]

Re: Correct '66 Vacuum Advance

...why all those B28s? None of your cars had a 1111236 as OE. Full deduction!

Duke

[Gene M.]

Re: Correct '66 Vacuum Advance

It's not an issue of equating it as missing. It has to do with the part configuration. The sheet metal stamping is not as original part configuration and stamping is TFP. The front forming is totally different. The issue would be the same for an solid state voltage regulator. Configuration as in appearance is not correct. Not minor, it is a major difference. Not close, incorrect full deduction.

[John H.]

Re: Correct '66 Vacuum Advance

...why all those B28s? None of your cars had a 1111236 as OE. Full deduction!

Duke

Duke -

Lots of '69 Z/28 fixes for others in the last few months...