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Premium Member
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Discussion Starter #1
Ive just completed a 2 year restoration on a 68 400HO 4 spd and need advice on what carb to use. The previous owner rebuit the motor with a 520 lift cam (not sure of the duration) and installed a dual plane alum intake with headers, and ported the heads ,the car has a pretty lopey idle. The carb is only a 650 cfm holley which seems pretty small I'm thinking I need at least a 750 cfm to be in the 450-500 range. Ive welded o2 bungs in the collectors to hook up my a/f ratio gauge to tune the carb if needed I just don't want to drop $500 on the wrong carb I would even consider a used carb any advice would be appreciated.
 

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64-67 Expert
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8,569 Posts
The original Q-jet, jetted and metered for your engine, would be the best performer. If that is not an option, yes, a Holley 700 or 750 would be helpful. Your 600 is on the small side for optimum top end performanc.
 
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