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Eagar1 · 08-23-2009, 10:44 PM

A progressive 2 barrel would be an excellent upgrade, and would not sacrifice too much mpg if you keep your foot out of it. you can get an adapter plate to mount on top of your existing intake, and it may even come with a vacuum port in it, or you can drill and tap one. You can actually take vacuum from anywhere off of the intake, even if you need to drill and tap a hole to do it. The diffence with getting vacuum off of a carb is whether it is ported vacuum that is metered depending on throttle position.
I have found that it is best on the older engines to get most of your advance from mechanical, and use the Vacuum to aid in Idle and off Idle response.

08-23-2009, 10:44 PM	#6
Eagar1 Registered User Join Date: Sep 2006 Location: Las Vegas, NV Posts: 169	Re: What did this carb come from? A progressive 2 barrel would be an excellent upgrade, and would not sacrifice too much mpg if you keep your foot out of it. you can get an adapter plate to mount on top of your existing intake, and it may even come with a vacuum port in it, or you can drill and tap one. You can actually take vacuum from anywhere off of the intake, even if you need to drill and tap a hole to do it. The diffence with getting vacuum off of a carb is whether it is ported vacuum that is metered depending on throttle position. I have found that it is best on the older engines to get most of your advance from mechanical, and use the Vacuum to aid in Idle and off Idle response.