Vacuum takeoff at carburetor

[Grant Bowker]

I'm sure there has been discussion of vacuum takeoff adapters that fit between carburetor and manifold in past but can't find it. If anyone else finds it, can they link the thread here (or move this post to go with the old one)?
Recently ebay yielded two different patterns of vacuum takeoff spacers. Both are sized for 1-9/16 throat, 3/8 mounting studs on 2-11/16 c-c. The thicker is just under 1/2 thick with the vacuum passage 5/16 at the outer end but only accepting a 1/4 drill at the inner end. It is possible it was originally 5/16 full length as there is some distortion in the plate at the inner end. The thinner version is just under 3/16 thick with the outlet as 1/8NPT. The open areas for vacuum flow are surprisingly similar give the difference in thickness. The thinner one might not need new studs while the thicker one probably would.

[Grant Bowker]

More photos of the individual vacuum takeoffs.

[Phil Waterman]

Hi Grant

The large plate type I believe was for the brake booster, but it may have also been used on the cars with vacuum assisted shifting. There was one earlier discussion of it for solving the problem of connecting the brake booster on manifolds that did not have the large side port (engine swaps or manifold replacements) look at the 6th post down on http://www.mapleleafup.net/forums/sh...ad.php?t=15589 .

I'm looking for the other discussion but my search is yielding to many possible threads or post to be useful.

One thing to check for is the diameter of the throat of the adapter plate as compared to the manifold and the carburetor the ones meant for the 216 engine will act as a restricter plate for the 235 and 261.

Also many of these engines where equipped with an insulating spacer between the manifold and the carb.

Cheers Phil

Cheers Phil