*Quick update to save time for anybody reading through the whole thread. I'd deceided to shelve the idea for now. Eventually I figured out comparing apples to apples at first glance a harely carb flows at 310cfm and autolite 2100 on the 302s was 287. But when you do the math for a level playing field on testing at the same vaccum the harley carb is showing 179 cfm. That's a little too low to be happy with. Eventually I might try it just for something different and see how it does but for now I'm going to stick to something conventional.
Ok I know I'll get some hate for this but hear me out. Im restoring a 71 bronco right now. The engine block was cracked so I found a great deal on a 2001 302 with 4r70w from an explorer for cheap. But it is nice to have a more modern engine with things like serp belt. It has everything to put the factory fuel injection back on it but efi just isn't my jam. CPU, miles of wiring ect, ect just isn't worth it to me. I'm pricing out a new intake manifold and carb I thought I might try something else first.
Harley CV carb goes up to 51mm they are rated around 270 cfm which is almost the exact number an autolite 2bbl that came on a lot of 302s back then. Without too much effort I could bolt it into place where the throttle body used to be. Factory intake has a 2.5" outlet of the harley carb is 2". With overdrive, 3.5 gears and my conservative driving habits it probably rarely see much about 4000 RMPs. So the numbers are telling me it will have enough air to keep the engine fed? The other element is it it will get enough fuel. Bigger jets will hopefully accommodate for this. Fuel bowl is small but the refill rate should be faster than what the engine can drink.
A few other examples. The 40mm harley carb is a very common swap for the samurai. Obviously a 5.0 is bigger than a 1.3. But this is a 51mm and not 40mm. Plus 8 cylinders aren't demanding air at the same time. So it would almost be like running a 2.5 literl 4 cylinder. There is a viral youtube video of someone that put a lawnmower carb on a 302 in a car (he claimed to get 40 mpg). He programed a computer controlled vaccum leak to make even out his fuel mix. He monitors his AFR gauge and they seems incredible consistant. Better than what I get on my holley sniper 2 on my other car. He also used LOTS of timing advance and had reasons for why. I used to have a 1960 pontiac ventura with a 400 in it and from the factory it had a tiny 1bbl carb (those were known to have some incredible mileage). I've seen the carb on the ford falcons 144 "thriftmaster" with the autolite 1100 the outlet was so small my pinky finger wouldn't fit into it.
So why? 1) I can buy the carb for $100 and then use what I'd otherwise just scap. If it works I'm saving $1000 on buying an intake and carb. If it doesn't work I'm in the exact same spot I am now and could swap it out and sell the harley carb. For that price it's worth trying just to see what happens. 2) The harley CV carb has some really great advantages. Being a CV carb hey run great off road, much less effected by elevation change, and keep an more constant AFR 3) It would have a great vacuum signal and low end torque and make up some of the difference running 31" tires will 3.5 gears would otherwise lack in. 4) Great atmozation of the fuel might even rival EFI. 5). For me and my conservative driving habbits MPG is a higher priroity than HP. Especially top end horsepower I will likely NEVER see. So any thoughts? Hopefully some more science, experience and opemindness as opposed to "it's too small it won't work."
Ok I know I'll get some hate for this but hear me out. Im restoring a 71 bronco right now. The engine block was cracked so I found a great deal on a 2001 302 with 4r70w from an explorer for cheap. But it is nice to have a more modern engine with things like serp belt. It has everything to put the factory fuel injection back on it but efi just isn't my jam. CPU, miles of wiring ect, ect just isn't worth it to me. I'm pricing out a new intake manifold and carb I thought I might try something else first.
Harley CV carb goes up to 51mm they are rated around 270 cfm which is almost the exact number an autolite 2bbl that came on a lot of 302s back then. Without too much effort I could bolt it into place where the throttle body used to be. Factory intake has a 2.5" outlet of the harley carb is 2". With overdrive, 3.5 gears and my conservative driving habits it probably rarely see much about 4000 RMPs. So the numbers are telling me it will have enough air to keep the engine fed? The other element is it it will get enough fuel. Bigger jets will hopefully accommodate for this. Fuel bowl is small but the refill rate should be faster than what the engine can drink.
A few other examples. The 40mm harley carb is a very common swap for the samurai. Obviously a 5.0 is bigger than a 1.3. But this is a 51mm and not 40mm. Plus 8 cylinders aren't demanding air at the same time. So it would almost be like running a 2.5 literl 4 cylinder. There is a viral youtube video of someone that put a lawnmower carb on a 302 in a car (he claimed to get 40 mpg). He programed a computer controlled vaccum leak to make even out his fuel mix. He monitors his AFR gauge and they seems incredible consistant. Better than what I get on my holley sniper 2 on my other car. He also used LOTS of timing advance and had reasons for why. I used to have a 1960 pontiac ventura with a 400 in it and from the factory it had a tiny 1bbl carb (those were known to have some incredible mileage). I've seen the carb on the ford falcons 144 "thriftmaster" with the autolite 1100 the outlet was so small my pinky finger wouldn't fit into it.
So why? 1) I can buy the carb for $100 and then use what I'd otherwise just scap. If it works I'm saving $1000 on buying an intake and carb. If it doesn't work I'm in the exact same spot I am now and could swap it out and sell the harley carb. For that price it's worth trying just to see what happens. 2) The harley CV carb has some really great advantages. Being a CV carb hey run great off road, much less effected by elevation change, and keep an more constant AFR 3) It would have a great vacuum signal and low end torque and make up some of the difference running 31" tires will 3.5 gears would otherwise lack in. 4) Great atmozation of the fuel might even rival EFI. 5). For me and my conservative driving habbits MPG is a higher priroity than HP. Especially top end horsepower I will likely NEVER see. So any thoughts? Hopefully some more science, experience and opemindness as opposed to "it's too small it won't work."
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