correct vac, advance from NAPA

[kelly theaker]

can anyone please advise me on the correct vac, advance for a 69 427-435 h/p . Part number would help also

[Joe L.]

Re: correct vac, advance from NAPA

kelly------

By "correct", I assume you mean FUNCTIONALLY correct per GM. If so, the NAPA-Echlin number is VC-680. This exact same control (stamped B1) is also available from GM under GM #1913850 or Delco #214-1066.

[Joe L.]

Correction

The GM part number should be 19138050 and NOT 1913850.

[Duke W.]

Re: correct vac, advance from NAPA

I recommend you install a VC-1765 and change from ported to full time vacuum advance.

Search archives from last summer using "L-71" and "VAC".

This issue with L-71s has been discussed many times before, a number of owners have made the change, and are extremely happy with the results.

Duke

[James B.]

Re: correct vac, advance from NAPA

What vacuum advance do you recommend for a basically stock '72 454 (w/4-Speed)? Many years ago, the distributor had been recurved by a machine shop for higher performance and the original vacuum advance travel was limited to minimize surging at low speed. At the time, I was living in Colorado (high altitude), but now live in Southern CA. The distributor is currently hooked-up to the TCS (ported vacuum), but I will bypass it for full vacuum, based on your earlier recommendations.

[Duke W.]

Re: correct vac, advance from NAPA

Depends. Is it a manual or auto trans? What is your typical idle/vacuum speed with about 25 deg. of TOTAL idle timing? If an auto trans it should be in Drive.

Duke

[John D.]

Re: correct vac, advance from NAPA

Duke,The VC1810 Vac. Advance from NAPA is history. Discontinued. I tried crossing over the number at Car Quest, etc. and got zip. Any ideas. As you know the VC 1810 was stamped B28 and we use it in lieu of the 236 16's.
Thanks, John D.

[Duke W.]

Re: correct vac, advance from NAPA

I don't know what brands Car Quest carries, but it can be crossed to BWD, Niehoff, and others on the Web. I'm not sure about Delco because they've changed all their part numbers, and I don't trust their catalog/cross reference.

The part is made by Standard Motor Products. Since so many have been bought in the last few years it looks like the inventory was depleted, and they need to manufacture another lot.

Someone needs to contact Standard.

Duke

[Richard S.]

Re: correct vac, advance from NAPA

John,

Whichever one you choose, I would check the vacuum very carefully before installing. When Duke was helping me with my 67 427/435 a while ago, we tested more the a few right out of the box....before we found one with correct spec. Hope this helps you and others in the future.

[John D.]

Re: correct vac, advance from NAPA

Duke, We contacted Standard and the part is history. They are not planning another run but a couple of my friends are working on the project. Not going to put the 236 16 on them foro some reason. I were going to do it myself I would be stamping them. They are not going to have any numbers or letters at all. Plain Janes I heard and just for the 30-30, etc. application since the B22's are still available. The repros are not within specs I heard.
Hint: Stock up on the B22's while the getting is good as when they are gone it's all over. I have a stock of the worthless B1's that I bought years ago from Chevy. Good paperweights. John D.