Slant 6 4bbl Carb Selection

Bewy said
Running a 750 cfm carb of any brand on a slant 6 that will be street driven is a baaad idea. The large primary barrels will nit be conducive to good throttle response. There is a reason why manufacturers select carb size commensurate with the engine size [ & at greater cost ] , rather than a one size fits all.

SpriceyStuff said

Hey guys. I want to do a performance slant six build, and I originally wanted to do a triple Weber setup. Since I don’t have the cash and Redline hasn’t been able to resume manufacture of the manifold, I’ve decided to cut my losses and just go for the cheaper 4bbl route. I’ve found a manifold that’s in stock, but I want some recommendations for what carb to put on it. I’ve bought a bigger cam, and I’m

SpriceyStuff said

Hey guys. I want to do a performance slant six build, and I originally wanted to do a triple Weber setup. Since I don’t have the cash and Redline hasn’t been able to resume manufacture of the manifold, I’ve decided to cut my losses and just go for the cheaper 4bbl route. I’ve found a manifold that’s in stock, but I want some recommendations for what carb to put on it. I’ve bought a bigger cam, and I’m planning a set of 3-2-1 headers for the exhaust. How many cfm can I make use of? I don’t wanna blast all my cash away on a bigger carb than I can actually use, but I also don’t wanna miss out on any gains by going smaller than I can. What do you guys think?

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planning a set of 3-2-1 headers for the exhaust. How many cfm can I make use of? I don’t wanna blast all my cash away on a bigger carb than I can actually use, but I also don’t wanna miss out on any gains by going smaller than I can. What do you guys think?

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SpriceyStuff said
Hey guys. I want to do a performance slant six build, and I originally wanted to do a triple Weber setup. Since I don’t have the cash and Redline hasn’t been able to resume manufacture of the manifold, I’ve decided to cut my losses and just go for the cheaper 4bbl route. I’ve found a manifold that’s in stock, but I want some recommendations for what carb to put on it. I’ve bought a bigger cam, and I’m planning a set of 3-2-1 headers for the exhaust. How many cfm can I make use of? I don’t wanna blast all my cash away on a bigger carb than I can actually use, but I also don’t wanna miss out on any gains by going smaller than I can. What do you guys think?

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If you use the AussieSpeed intake, it has no heat to aid atomization and vaporization of the fuel. A carburetor with annular boosters has better signal and they do a better job of atomizing the fuel than standard boosters. The Edelbrock AVS2 carbs have annular primary boosters. If your intended use is primarily a snappy street engine, I would go with a 500 CFM 1901 with electric choke.
You can put the annular boosters into Performer Series carbs. Edelbrock tech suggests starting with the equivalent AVS2 calibration. That appears richer, but remember that todays pumo fuels contain 10% to 15% ethanol, which requires richer "jetting" to maintain the proper A/F ratio. Edelbrock does not sell the boosters separately. If you get a Performer 500 or 600, contact Dan at The Carburetor Shop in Minnesota. A new cover gasket will be supplied with the boosters. Also purchase a calibration kit for the equivalent AVS2 carburetor.
IMHO, unless racing only, the 1407 is too much for a street slant. Either keep it for a built a bit 360 ir sell it and use the money towards a 1901 Edelbrock.
Regarding the headers, don't you mean 6 into 2 into 1? I would seriously consider headers that provide ground clearance for a street driven vehicle. The low hanging tubes can get flattened real quick on speed bumps and such. Exit stage left any advantage they may have provided.