would an A carb on a B manifold have less power than A on A?

[BRENT in 10-uh-C]

Originally Posted by philosofriend

Would an A carb on a B manifold have less power than an A carb on an A manifold?

I have to take my old manifold off and I'm thinking about getting a B carb. I want to put it back together (with a new Burtz block) but I won't have a B carb for a while. Seems like I might as well use Snyders manifold that is bored out for a B carb now and save having to change the manifold later.

The B manifold won't make the A carb run rough or anything, will it?

Yes, it could but not enough for you to notice by the seat of your pants. The reason would be where the transition at the flanges is about a 0.120" per side that would momentarily cause a low pressure area which could cause the fuel to fall out of suspension. Again, you likely will never notice unless the engine was being run on a dyno.

The one thing you likely won't like about using a 'B' manifold is the carburetor will not sit at the same angle as what it did on the 'A' manifold. This affects connecting the choke rod. Elongating the carburetor mounting holes in the flange will let you twist it somewhat but it is not a 100% fix.