[idoxlr8]

I have been lucky enough to be able to try a few different carbs, Here are my impressions. First the motor setup:
.030 over 350
Lunati solid cam, .519/.534, 256*/270* @ .050
3rd version World Products Sportsman II heads, port back in 1995 by Dutwieller, 2.05 intake,1.60 exhaust
Edlebrock Victor JR port matched
MSD billet distributor 14* intial, 36*total in @ 3000, MSD 6AL
Hooker Super Comps 1 3/4" pri, 3" collector
Turbo 350 w/3000 stall
12 bolt w/3.90 posi
I used new plugs each time and have them all a chocolate/light brown during street use, I have driven the car to and from work (about 27 miles each way in traffic) for five days with each carb to evaluate them.

My Carb,
780cfm (3310-1) Vacumm Sec. Holley with a proform main body/added secondary meetering block.
71jets front, 82 jets rear, 6.5 PV, lightest spring, 37 squirter.
Carb runs alittle rich at Idle, Pulls hard and runs great on the street. Great throttle respone No Bog or hesitation. At the track it has run a best of 8.98 @92 mph in the 1/8th.

Next carb,
650 Barry Grant Speed Demon, Mech secondaries.
70 jets front, 78 jets rear, 6.5 PV, 28 squirter.
Carbs idles Clean (this carb has the Idle Ease), Very easy to tune, Very CRISP throttle respone, no BOG or hesitaiton, But it has a lean miss at cruise no matter what tune up I throw at it.

Next Carb,
700cfm (4778) mech sec Holley
72 jets front, 81 jets rear, 5.5 PV, 37 squirter.
Carb idles smooth, just a tad rich on a hot humid day, Crisp throttle respone, no BOG or hesitation, Cruises great and seems to pull harder to the top end with less RPM Drop at gear change. Best street manners out of all that I have tried.

Last Carb
750 Barry Grant Race Demon, Mech secondaries.
75 jets front, 83 jets rear, 6.5 PV, 31 squirter.
Could not get this thing to Idle worth a @#$%, Tried to drive it and all it did was spit sputter and cough, Tried to go full throttle and the motor pulled throught the mid range then fell flat from about 4800 RPM and up.
Carb way to big for my application.

I will get some track data on the three that I can get to run as soon as the weather clears up around here on a Friday night, Rain for the last three weekends.

[kelemor]

Iam surprised the demon is running so poorly, one question is the demon used or is it new out of the box. The reason i ask is i run an 825 race demon on my 383 which is pretty close to your combo minus the 30 cubes and the carb performs very well BUT when i first installed the carb i was having some problems i couldnt figure out that turned out to be some aluminum castings rolling around in the float bowls. I kept the offending little buggers and hopefully this friday i can personally hand them to Barry In Seattle at the track if he is racing. Other than that I have been really happy with the carb no bog crisp throttle and so far has performed nicely at the track.

[dylanjans]

Is it really 256/270 at .050?
That seems kind of ginormous.
I'd imagine it winds pretty good!

[rolling-robert]

i was thinking the exact same thing, hehe, better remove the "@0.50"

[idoxlr8]

Nope No trash in the bowls of the Race Demon, I have had them off trying to rejet it. No Joy!

That's how the Cam card reads (256*/270* @ .050") Lunati P/N 00013LK.