I just bought a 73 Mustang 351 cleveland, and i need to change out my oild holley carb in it. I am split on which way to go. Holley has been know as the best but all the results that i see show Speed Demon to be the stronger of the two. I was wondering what people here thought or if they have tried teh speed demon carbs. My goal on this car is to get it as close to 400hp as possible so i am looking for the best one to do that as well. At the moment is i fairly unmodified except for a mild racing cam. Thanks for any imput on my first bug decison on this project.
I would say holley. The parts from berry grant are harder to get a hold of and are weay more expensive... Some stuff is interchangeable like jets and some of the metering block and bowl gaskets. Your lookin cheaper with a holley too. I mean if you compare a street avenger to a road demon they are around the same price... I would get the street avenger. If you want more reasons PM me.
Holley street avenger 670 CFM (0-80670) $375.99
Road demon Vacuum sec. electric choke 625 CFM (4282010VFE) $ 379.99
(These are my store prices. Just something to compare to)
A Demon is a modified Holley. What you pay for and what you get go with the Demon.
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Black,79 Mustang mostly carbon fiber/kevlar body, M-2300-k brake kit, full roll cage, maximum motorsport suspension, custom geared 6 speed, 2 inch rear fender flares, 1 inch front, motor being built (no eta). Looks like the Mad Max interseptor and weighs about 1800lbs w/o motor (450hp 351w installed to move the car around)
Black, 82 Capri RS 5.0L, B303, 1.7 rockers, World 180 heads, +150hp N.O.S, Turbo coupe rear end, T-56(tremec tko would be beter), 80 cobra nose
demon carbs are a step above the basic holleys. something like a keith dorton series holley is equivelent. the only problem i had with demons is that they are jetted on the rich side. go to barry grant.com or demon carbs.com. they have guidelines to help choose the right size and model.
I just put a Holley (model #4160, 750cfm, vacuum secondaries, dual fuel-inlets) on My T-bird, and I LOVE the increases in power and driveability over the factory AFB/Motorcraft carb (which I've been told is 850 cfm)
I'd say Holley, I bought one for the car back in January, and after trying for 3 months to get it working right I took it back, and my Holley dealer didn't give me any problems about it, they just gave me a brand-new one off the shelf!
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1976 Ford Mustang II Ghia: 302 with a 600cfm Edelbrock carb, Edelbrock Performer 289 intake, Dynomax Blackjack headers, 2.5" exhaust with Flowmaster Super 44s. RJS 11-gallon fuel cell, C4 tranny, chrome 16" pony wheels, fuzzy dice, brown vinyl half-top, and painted in the tackiest color ever (harvest gold, that's why I call it "The Goldenrod").
Also have a 2003 Dodge Ram (lightly modded daily driver/tow rig/office/dining room/home away from home/workshop... I call it "The Big Blue Dawg".)
Holley vs Speed Demon, which will work best 
