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Looking for advice and experience help on deciding what carb to buy. Finishing new sbf 9.5 deck 427, AFR 220, solid roller engine for my 63 Fairlane drag car and need a carb. Does anyone know about Willy's carbs out of Illinois?? Need a naturally aspirated carb, no power adders. I like the idea of Willy's adjustable jet design, but have no experience with his carbs. When I called and talked to him, he suggested one of his 750 carbs. A 427 turning 7500rpm, that just sounds too small to me and my passed experience. Am I wrong? Any suggestions for a different company?? Or try a Willy's?

Thanks for any and all comments
 

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750 indeed sounds too small, depending on what cam, intake, and header size that you plan to run. My built NA 434 requires a 1050 cfm carb to do 7500 rpm shifts and run out the back door crossing at 8000.

First tried my old trusty 830 cfm Holley HP and then installed a new 4150 Braswell carb in the heat of summer and gained 1/2 second and several MPH.
 

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I would use a 950hp or bigger as Dennis has. You have some good cylinder heads and plenty of cubic inches so let it breath. That engine would easily handle dual quads.
Randy
 

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Ok this is a drag racing forum so carb sizing is more dependent on demand that desire. There are countless superstock cars (think 428 cobra Jets) that run in the low to mid 9 second range and have a 735 vacuum secondary carb. Carb size is a balancing act for drag racing unless you have a huge converter, transbrake and a throttle stop. A 650 will flow around 740 with no work, 750 Holley will actually flow around 840 and so on. A worked 750 with shaved shafts and milled horn can go over 900. It would not be any kind of stretch to make the best power on a 1000+ cfm carb but the car may not 60ft for crap. Booster placement and signal are a huge deal. Reasonably., Your package will probably run the best et's with somewhere around an 850-890 cfm. Not whatever arbitrary carb size but actual flow. Converter size,compression, gearing and cam specs will dictate booster configuration and size based on vacuum and a few other factors. If your not sure and want to try some things the please work your way up. Too big of a carb usually can still get good mph on the big end but bad short times and slower overall et. Also remember that bigger venturis may flow more but the diminished signal on the booster will wreak havock on mixture. Intake velocity that is incorrect will actually cause fuel to droo out of atomization and cost tons of power while also being a nightmare to tune.
 

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So yes a built and worked 750 ( which probably flows 875-925) would be about right. Sounds like your carb builder is dead on with his numbers
 

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Give AED a call. They can set you up... and are very good at getting it right the first time. A hot 427 turning that rpm is going to need about as much as you can get out of a 4150 style carb.


Not quite as cheap as buying one out of Summit, but not that much more, either.

Those Super Stockers go that fast -despite- having to run those small carbs... not because of it. Putting a bigger race carb on them would definitely pick them up.
 

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I agree with Mike that more carb is definitely needed for a high rev'ing stroker.

Before I went for the 1050 mentioned above I tried a new QFT 850 racing carb thinking it would make a huge difference over the old 830 cfm 950 HP. I messed with jetting/timing/etc but didn't see an iota of difference in mph (or ET.) Later I ran the combo through pipe max and found that I needed a larger (55-59) venturi to make peak HP at 7500rpm. That's when I sprung for the larger 4150 Braswell with a 58 venturi. At first it too ran about the same as the worked 830/850 but when I increased the jetting 3 sizes per hole it ran much, much harder in mid-summer temps-literally gaining 1/2 second. That power remained on later outings so I knew the carb swap made all the difference in the world. Its best was an [email protected] 140+ mph pushing 3550lbs of NA street car.
 

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Looking for advice and experience help on deciding what carb to buy. Finishing new sbf 9.5 deck 427, AFR 220, solid roller engine for my 63 Fairlane drag car and need a carb. Does anyone know about Willy's carbs out of Illinois?? Need a naturally aspirated carb, no power adders. I like the idea of Willy's adjustable jet design, but have no experience with his carbs. When I called and talked to him, he suggested one of his 750 carbs. A 427 turning 7500rpm, that just sounds too small to me and my passed experience. Am I wrong? Any suggestions for a different company?? Or try a Willy's?

Thanks for any and all comments
Willy was one of my customers at a past jib I had. I he knows his you know what about carburetors. I thought he was more focused on roundy round cars or circle track type stuff?
Quick Fuel makes an outstanding carburetor. I would recommend a 750-850 for sure. If its more a street car, than 750 will get you better street performance. If it's a full time race car, then the 850 would be the ticket.
 
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