I'm partial to Carter carbs myself, but since they're no longer available I'd go with the Edelbrock Performer, 600cfm for general street use. You're probably going to need to do some mild work to bolt it on in place of the Holley. Do you have/want/need an electric or manual choke? Linkage and fuel lines may need some changes made to them depending on what you have now. And for best performance it should be jetted/tuned to your application and altitude, though it'll work out of the box.

I'd stay with the R4B, it's a good intake and hard to find. If you do end up replacing it with a polished intake DON'T sell the R4B.



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