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airdale94 · 11-20-2013, 05:22 PM

If your idle is to high you will get vacuum on your ported port. If your carb. needs rebuilt and consequently you have your idle screw in far enough that your throttle plates are pass the bleed for the ported port just to get it to idle, then yes you will have 2 full vacuum ports. You shouldn't be losing that much vacuum with the choke on and fast idle cam engaged. I would say your choke is to rich.

11-20-2013, 05:22 PM	#2
airdale94 Registered User Join Date: Jan 2007 Location: Topeka,KS Posts: 778	Re: Too much Vacuum Advance If your idle is to high you will get vacuum on your ported port. If your carb. needs rebuilt and consequently you have your idle screw in far enough that your throttle plates are pass the bleed for the ported port just to get it to idle, then yes you will have 2 full vacuum ports. You shouldn't be losing that much vacuum with the choke on and fast idle cam engaged. I would say your choke is to rich. __________________ 68' C20. 283CI w/55CC 305HO heads, NP435 Close Ratio, Corp. 14 bolt FF 3.21, 75' front end swap (everything but the X-member).