DEMON CARB

[mopar1968]

:?: ANYONE OUT THERE RUN A DEMON CARB :?:

[margaritaman]

750 times 2

[mopar1968]

this is my first one, ran holleys for years anything special i might need to know? it is a 750 cfm

[v8Fiero]

I have a one on my old motor, only thing I can think of for you, BG recomends to run a little higher fuel pressuer then holleys or other. I believe they are optimal at 7-8psi while others can be recomended 5-7. check with them for your carb because I think it ranges slightly from speed demon to road demon to mighty demon, etc. other then that I have had good luck with mine since Ive owned it.

[curtisreed]

Had an alcohol 825 race demon we ran. Found that the needle and seats would not flow as good as an old set we had in a Holley we were using. Changed them out (both were .150"), picked up about 30hp by that alone checking on the dyno. Ran great and was easy to predict on the motor we had. We put on a Ron's injector and didn't pick of a hundredth. I really liked it and wish we wouldn't have gotten rid of it even though there is no comparison to the throttle response of the injector.

Curtis

[mopar1968]

:?: will a holley pump diaphram fit this carb? i traded for this one , on here runs good just leaks fuel from front pump!

[insane4fbodys]

I'm glad to see all the positive input about Demon carbs, so I'll be the bad apple. I have had 3 different Demons and everytime I changed out for a Holley my cars always ran better. Maybe I don't know what I'm doing but track times don't lie. And I always swapped for the same size Holley carb that I had in the Demon. Just my exprience with these. But I will say I love the looks of them :D

[mopar1968]

I bracket race so i will take performance over looks anyday, but will a holley pump fit a demon?

[margaritaman]

Yes the parts are interchangable. I've heard that the jets flow a bit different so if you use Holley jets stick with Holley, Demons then stick with Demons.

Demons also work better with a bit more advance than a similar Holley. I have no idea why, they just do.

You either love them or hate them or love to hate them.

Most folks that I hear complain about them is when it comes to the idle circuit and the fact they run fat. If you remember to throw some more advance in there and the fact they all have four corner idle screws then you should be fine.

[mopar1968]

Yes i did notice that it seemed to run somewhat fatter than the holley, this is on a small block dyno at 591 hp, i think i will try it, carbs aren't hard to swap out. thank you for your help, this is my first demon.

[jmarksdragster]

The nice thing about the Demon is the adjustable bleeds. Does yours have the adjustable idle air circuit down the air cleaner screw hole? Make sure your throttle plates are not open too much, it works just like you would drill holes in the throttle plates of a Holley on an engine with a larger cam. You could also go up a little on the IAB's if necessary. Most of the flack I've heard about Demon's can be traced to the fact that they usually need to be tuned more than an out of the box Holley.

[tcarda]

I bought a 1000 cfm drag race demon carb from summit racing and when I dynoed my motor the dyno guy had a 1000 hp holley and both were "out of the box" carbs. The holley made 3-4 more hp across the curve, but it also lost 4-5 ft lbs of torque across the curve as well compared to the demon. Thats just my experience with them.

[mopar1968]

Yes mine has adjustable air bleeds, it is only two months old, got the diaphram fixed, seems to run out damn good, tested on my test track, WHEELS UP 1 1/2 FEET !! :shock: :shock: :D :D