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GRX · 12-01-2015, 04:03 PM

^^^ that. Well said. "CFM rating" is not really a good way to judge a Q-Jet. The rating is the max the carb will flow. Q-jet for smaller cube engines like 305s have a tab on their air valve that limits its travel, thereby lowering "CFM rating". In the right hands one can be modified to provide up to and over 1,100 CFM. Then you have the fact they require different jet sizes and metering rods depending on the application. Main reason inexperienced re-builders get into trouble.

To answer the original question ... I would go a for a Q-jet, but I have been working with them for a couple decades. Many would benefit from the more simple, and less tunable, Edelbrock plug & play AFB clone carb.

12-01-2015, 04:03 PM	#10
GRX Registered User Join Date: Jul 2010 Location: MD Posts: 1,937	Re: choosing the right carb ^^^ that. Well said. "CFM rating" is not really a good way to judge a Q-Jet. The rating is the max the carb will flow. Q-jet for smaller cube engines like 305s have a tab on their air valve that limits its travel, thereby lowering "CFM rating". In the right hands one can be modified to provide up to and over 1,100 CFM. Then you have the fact they require different jet sizes and metering rods depending on the application. Main reason inexperienced re-builders get into trouble. To answer the original question ... I would go a for a Q-jet, but I have been working with them for a couple decades. Many would benefit from the more simple, and less tunable, Edelbrock plug & play AFB clone carb. __________________ 1969 c-10 Step Side Long Bed. I-6 250cid = = 1969 Pontiac GTO hard top. 400, 4-speed.