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2 barrel or four barrel carb

W

walleye52753

Well-known member
stock chevy 400 DD. What carb would you guys recommend for this setup? Its not the high performance engine that I had originally planned on running but its completely rebuilt (with stock truck heads) and the price was right! :wink: Should I run a 500 2barrel or a doublepumper? as of now i was planning on running a performer rpm intake. Any advice on a different intake would be much appreciated also.
thanks
andy
 
remember its only turnin no more than 3,000 rpms,stick with the 500cfm and the performer intake manifold you are def on the rite trac.good luck and care
 
THE 2 BAR WILL BE FINE FOR YOUR SET UP I HAVE OWNED A SBC D/D AND HAD A 650 CFM WITH A PERFORMER INTAKE AND DID GREAT IF YOU CAN ONLY SPIN 3000 RPMS WHY SPEND MONEY ON UPGRADES THAT WONT BE USED LIKE THEY SHOULD JUST STAY ON TRACK U'LL BE FINE
 
ok, i just talked to a friend that runs 2 barrels on his circle track car and he claims that i will get worse gas mileage at low RPM with a 2 barrel than a 4. His argument was that the 2 barrel has larger jets to accomodate a higher RPM range without the secondary jets and that I will burn more gas below 3000 RPMS! OK LETS HEAR IT! If you add in the price of a good 2-4 barrel adapter for a dual plane intake a 600 holley and a 500 holley are about the same price.
thanks
andy
 
well, so much for this topic. I just bought a 500 holley circle track carb.I guess i just thought it could have been an interesting topic even though it wasnt feeding a 600 horse powerplant. guess ill never know. For the guys that did give me info.... very appreciative.
thanks
andy
 
Some times it takes a little while for the right person to reply. I'm not that person but i think you can tune that 500 to work great for you. should be responsive. there are some cool tricks to make her jump but i don't claim to be a Holly man. Good luck with it brother :)
 
Hey Andy, It is a good topic but some of us were working on other treads and ran out
of time. With the prop holding you below 3000 RPM's , your engine will only be pulling
about 300 CFM of air. Any carb over 500 CFM is way to big. Most everyone uses
the 500 2 barrel Holley. I recommend the Edelbrock 500 CFM 4 barrel, part # 1404.
The primary bores are small with annular style boosters. This increases the speed of
the air thru the venturi and produces better air/fuel mixing. The accelerator pump is
adjustable and you don't have to buy a carb spacer. If you try one, set the idle screws
to 1 3/4 turns and fine tune from there. Thanks, Chuck
 
Thank you chuck. Tremendous help. So am i hearing you correctly? The edelbrock 2 barrel has a square flange bolt pattern?
 
There's a lot of ways to skin a cat and this is actually a topicthat's been gone over considerably before. Sorry I didn't repost because I've posted a few time on the matter as well as others. Your buddy's right about the 500. THE reason the 4-barrel carb was invented was due to having the venturis too large when feeding bigger and bigger engines. The more venturis and boosters you can spread the work amongst, the smaller and more efficient you can make them. The 500 is rated at a different pressure drop than a 4-barrel and only flows about 390 when flowed under the same test pressure as a 4-barrell. In comparison to a 4-barrell the 4412 needs a richer mixture tokeep from stumbling with it's large throttle bores and venturis, and subsequently will fatten up at higher RPM, I've told as many people as I can that in a DD I prefer the 390 Holley 4-barrell. It flows just as much and has a MUCH better fuel curve. The 450 and 465 budget Holleys will work well to, as will the Edelbrock/Carter 500, but the 390 double pumper will be king.

I could go on more as to why, but you've already purchased a carb, and you can find the info by searching old threads.

Felber
 
Thanks Felber, The 390 is king, I've had trouble selling them due to cost when it is
a budget boat. I've made the 500 Edelbrock work good for about half the money.
I wish we could buy the 390 for about $ 250.00. :) Thanks, Chuck
 
wow...(brief pause) cant buy that kind of info. Never thought of a 390 double pumper. What do they run pricewise?

on another semi-unrelated topic. We run 500 holleys on our demo cars because they dont load up on us at high rpm's. As im sure you know, too much fuel isnt good with a scorching hot motor. When they stall they dont like to start. Could a 390 be a possible advantage to this scenario? 350-425hp sbc's?

Thanks for your time guys, a little bit of info goes a long ways for someone that needs a little guidance.
Andy
 
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