fulo

Does anyone have experience with demons carburators???

I am considering a Speed Demon 650 cfm.. for my GM ZZ3 engine.

I want a carburator that I can easily tune, that will hold a tune, that give me the fredon to adjust the air/fuel mixture (as opose to changin jets), and I want some fuel efficiency and lean emissions.. I am looking for something reliable.

I only have experience with electronic Q-jets, Can i use a holley technical manual to guide my seld with a DEMON carburator?

Any other carburator suggestion???

greearhr

i'm running a Speed Demon 750 on a 400 or so HP 400ci (Non Chev). They seem to run a little rich at idle, have too much choke plate, not enough fast idle and flow more than the rating. They are a bit pricy and you may need thier fuel inlet kit and choke to boot. That said I like em a lot! It runs like stink, you can modify the idle/choke and the woo, woo factor is vey high.

Beartracks

Polecat

I had a Demon 750 on my 383, and they do run really rich at idle. I tinkered with mine for months,finally sold it and bought a Holley 750cfm DP,model #4779 and set it, jet it and it's been fine. IMHO, I wouldn't buy another Demon, the Holley #4779 is alot easier to tune,and leave it be.

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350 4 bolt main, Speed-O-Motive 383 stroker kit, re-sized rods ground for clearance,TRW Forged pistons,10.7:1 compression,HPC Coated RPM intake, Holley 750 cfm carb,World Products Sportsman II heads,2.02/1.60 valves, Comp Cam 1.6 roller rockers, Comp Xtreme 284 cam,240/246@.050 with .540 lift,Crane pushrods,ATI damper,Proform HEI and MSD6A box,HPC coated 1 5/8 headers, 2.5" exhaust with 40 series mufflers,TH350 with Hughes 3000 stall, Powertrax NoSlip Locker, 4.11 gears.

CarNDrvr

That's the truth!!! THe demon's suck are way too hard to tune. I had an 850cfm race demon on a big block, and it had an off idle bog, and crap throttle response. I highly recommend a Holley 650hp series carb. Or the 750hp carb if you are putting out some pretty good horsepower.

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1991 Camaro RS, approximately 500hp 355, 11:1 compression, Eagle h-beam rods, forged steel crank, TRW lightweight 2 valve relief pistons, comp cams hydraulic roller, fully ported Dart Iron Eagle heads, Victor Jr., Holley 750, Hooker shorty headers w/3" collector, true dual 3" exhaust, Moroso spiral mufflers, T56 6-speed, Boyd Coddington 17x9, 17x11 wheels, 275/40zr17 fronts, 315/35zr17 rears, Cerillo racing seats w/ harnesses, Harwood cowl hood, 4:10 posi, Global West adjustable rear suspension, panhard bar and torque arm, Hotchkis front and rear springs, 1LE sway bars, Koni adjustable shocks.