<VV> Single Carburetor

[Joel McGregor]

What do you mean by vacuum retard?  If you mean higher vacuum produces less advance then you have something really weird going on.  If you mean that when you take off the advance falls off then that is exactly what a vacuum advance does.  At maximum vacuum it has maximum advance.  At lower vacuum it has less advance.  Ported vacuum won't come in until the port is uncovered but if there is enough throttle opening to lower the manifold vacuum you won't get a lot of advance.  The most you'll get is when the port is just uncovered with no load.  As you add load the advance falls off to nothing at maximum load.

Joel McGregor

________________________________________
From: virtualvairs-bounces at corvair.org [virtualvairs-bounces at corvair.org] on behalf of John Ingram [johnvi at cloud9.net]
Sent: Monday, April 22, 2013 1:34 PM
To: Virtual Vairs
Subject: <VV> Single Carburetor

I have a 65 110 that I have rigged with a single Rochester 2 barrel
Carb.  Runs fine, idles fine, the problem is the engine doesn't have
much low end torque, once I'm moving along it is okay but off the
line I need to keep the revs up.  I think the drop in vacuum from a
carb that may be too big is throwing off the timing, the distributer
vacuum retards the timing when I press on the gas to start out.  Does
anyone have experience with these single carb applications?  any ideas?

Thank you,
John I.