carb question

[hotrodtodd93]

Im buying a 786 cfm demon carb to upgrade from my edelbrock. I dont know much about it. The demon website is "in transition" so it is no help. Does anyone have info on this carb? How much better or worse is it than other carbs? Anything would be much appreciated.

[Rocket Power]

I'm pretty sure Barry Grant is out of business now.

[Rocket Power]

Yep.

http://www.dragzine.com/news/barry-grant-inc-ceases-operations/

[badass88gt]

Are you buying it new? If so, first step is to totally dismantle the carb and clean every inch. Demon carbs are notorious for having all sorts of shit left in them from manufacturing.

[Reverend Cooper]

Barry Grant is no more,imo you better off with a holley. of all the people i have known over the years and year there is a few that have a good one,the demon carbs have lots of issues,and dans right alot of it stems from initial manufacturing and assy.

[bikedad]

Holley's are great for power, fairly easy to tune but suck gas like there's no tomorrow. Carry a small screw driver with you for constant adjustments.

Edelbrocks are good right out of the box. They're easy and quick to tune but, you need to be a CFM/AFR scientist to understand all the different options.

I've run both types on my car. I liked the Holley but not the constant adjustments and terrible gas mileage.
I'm currently running an Edelbrock and am happy with it but it doesn't have the hit like the Holley. I've only had to change the pull up springs to match my cam and have not touched it since.

I bought the Edelbrock from advise of the guy who helped me with my engine specs but I have no allegiance to either Holley or Edelbrock.
I believe Demon is out of business or manufactured by a different distributor now.

[Prince Valiant]

Shouldn't need to carry a small screw driver to get good gas mileage out of a holley...just need to know how to tune-em right the first time :) FTR, most who complain of poor gas mileage in a holley either a) have a mechanical secondary (impossible to really get good mileage with) or b) Have a bad, or incorrectly selected Power valve.

First off, to the OP: What carb is this? Vacuum? Mechanical? For what engine?

Operationally, Demons are like Holley's, but often with features that make it more tuneable, and generally easier to "wrench on"...or some might also say, easier to screw up.

As others have stated, Demon's manufacture is out of business, so I don't know what that means going forward. Will you be able to buy parts to rebuild? Tune/fine tune? I don't know...so you're taking a risk buying one.

Once you get one and make sure that it's clean and in good order, they'll generally work well out of the box if you selected the right carb for the right combo (IE, the carb is best suited to engine build and chassis it's installed in).

Given that the same is true of Holley, you may want to look into one of those. What's your engine, build, car, trans, gears, converter and purpose/use? Those are but some of the questions you'll want to answer when selecting a good carb, be it a Holley or an Eddy....

[Reverend Cooper]

never had any issues on the holleys on my older carbed cars but then again between myself my brother and dad they all know wtf they are doing

[jbiscuit]

I'D STAY AWAY FROM THE DEMONS! Go Holley and be done with it

[Irish]

Are you buying it new? If so, first step is to totally dismantle the carb and clean every inch. Demon carbs are notorious for having all sorts of shit left in them from manufacturing.

This!!!! I'd run a quadrajet or a thermoquad before I would run a Demon.

They are called demons because you go through hell trying to get them to work!

[badass88gt]

There is no reason you can't get decent fuel economy out of a Holley. Get a carb with replaceable air bleeds, emulsion circuits, etc. and get yourself a wideband. I got just over 20mpg out of my car with my Quick Fuel 750HP on it.

[hotrodtodd93]

Alot of you asked about my set up. Here you go: 78 LeMans, vortec 355 with .510 springs, edelbrock carb, Rpm intake and cam 234 IN 244 EX .488IN .510EX, th350 with shift kit, 2400-2600 converter, 7.5 10 bolt posi with 3.42 gears.

[Prince Valiant]

I think an ideal carb for you would probably be something like the holley avenger series carb, 670cfm. You got a decent sized cam, but probably need a little more stall and gears to make a mechanical secondary carb or larger vacuum secondary really work well.

With a similar build and a manual trans I've run as small as a 600 cfm vacuum carb (needed to use the lightest secondary spring) to as large as a 750 mechanical. For a street car that sometimes races, I personally go with smaller carbs than most select for their own rides.

Nice thing about the avenger series is it's pretty tuneable out of the box for what most people would want/need (ie, two corner idle adjustable, adjustable floats, quick change secondary springs, changeable primary and secondary jets and all the things to make it easy such as reusable gaskets).

[juicedimpss]

This!!!! I'd run a quadrajet or a thermoquad before I would run a Demon.

They are called demons because you go through hell trying to get them to work!

x2
get a regular old holley or if you want something nicer yet,c&s specialties aerosal carb.

[BR3W CITY]

i ran a 670 street avenger on a very similar 355 setup in my truck. Overall it was a pretty good carb, but i had issues with tip-in and had a hard time trying to get it straightened out...just ended up putting a fuel injected motor in.

[Racer X79]

I've had decent luck with Demons, but with them going bankrupt and then being bought up by Holley this summer I'd stay away for now. I have had almost the exact same engine combo and I agree that the 670 Avenger is probally the perfect carb for it. They are jetted pretty lean out of the box so I'd switch to a 70 primary/74 secondary jet and pick up a vacum secondary spring kit with it, and run the short yellow spring to start. Set your idle mixture screws to 2 1/2 ish turns out and you should be all set.

[BR3W CITY]

and that makes 1000 posts yay

[Gregor]

http://www.summitracing.com/parts/QFT-HR-680-VS/?rtype=10

[Karps TA]

I had zero issues with my Demon that were not caused by my own inability to tune a carb worth a shit. It had many features that came std over the Holley I appreciated, like the glass sight bowls instead of the stupid plastic plug.

That said carbs suck, and I never want to deal with one again. lol