[77pontolds]

Does anyone have experience with a Demon carb? I am now using an AFB (really, not an edelbrock) and wonder if I can gain anything by going to a similiar CFM Demon. The design with the blended and smooth bores seems like it would in itself make more HP. I have shied away from Holleys due to leakage, but it looks like these other folks have solved that problem. I have always liked the fact that one can change jets and metering rods on an AFB type without loosing fuel and removing the carb. Thanks, Uncle Rich

[vinniekq2]

I bought an 830 demon for my 434,used it a year,gave it away.

[Motochris]

Are you referring to the new "Street Demon" 625 carb? That's the only Demon that uses metering rods. The rest are much like a Holley.

Here's a quick review I did on the 625-- New Demon "Street Demon" 625cfm carb

[lmsport]

The Edelbrock/AFB/AVS carbs are somewhat more daily driver friendly than a Holley-type carb. A QJet really is the best daily driver carb but finding a suitable one and then tuning to the particular engine can be a chore even if you are familiar with them. A Holley-type will almost always make the most power for the least effort and are so simple anyone can get one close to optimum.

[malc]

I think my 750 Speed Demon is great, no problems......
except when I installed the wrong body to baseplate gasket.....

[gearheadslife]

Originally Posted by malc

I think my 750 Speed Demon is great, no problems......
except when I installed the wrong body to baseplate gasket.....

same here.. no problems..
with my demon or bearclaw

[632Mantis]

I have an 850 Mighty Demon on my big block engine. I bought it back in 2005 I think.

Things I had to do to it:

Send the metering blocks back for exchange because the idle screw holes were drilled improperly. ( they were offset, they didn't line-up which caused the idle adjuster needles to break when you screwed them all the way in )
Change the power valve.
Change the jetting. ( It was ridiculously pig-rich. Came with 86pri and 94sec jets. )
Add notched float and jet extenders on the secondary side.

After all that.... it works great now!

lol

[ap72]

Originally Posted by Motochris

Are you referring to the new "Street Demon" 625 carb? That's the only Demon that uses metering rods. The rest are much like a Holley.

Here's a quick review I did on the 625-- New Demon "Street Demon" 625cfm carb

I have not used one of these but if I had to buy a new carb for a mild street car this one would be it. I also love the edelbrock 1406's I've used but this Demon seems to have a more refined design.

I've used holley's too and while they have a LOT more aftermarket support and options they really don't preform as well on a MILD STREET engine. A race engine is a different story.

I never saw the appeal of a quadrajet.

[gearheadslife]

Originally Posted by ap72

.

I never saw the appeal of a quadrajet.

really.. this carb will stay closer to a correct a/f than any other

[ap72]

Originally Posted by gearheadslife

really.. this carb will stay closer to a correct a/f than any other

no, not really. You can tune any carb to get close to the desired AF ratio you want, and a BOX STOCK 1406 is pretty damn close on most mild 350's- for a cheap carb that is.

[77pontolds]

Actually, I was looking at a Speed Demon 650 cfm electric choke. I was hoping to improve the performance of my 400 Pontiac over what the AFB provides.

[vinniekq2]

I doubt that there would much if any HP improvement.

[WDCreech]

I, like gearheadslife, think that the Quadrajet is the best street carb ever built. Because it has an air valve controlled secondary, you can't be over carburated. Once you get it tuned, it will do an excellent job!

Bill

[ap72]

Originally Posted by WDCreech

I, like gearheadslife, think that the Quadrajet is the best street carb ever built. Because it has an air valve controlled secondary, you can't be over carburated. Once you get it tuned, it will do an excellent job!

Bill

as does every carb with a vacuum secondary... the edelbrocks and the new demon 625 has secondaries that work off of airspeed instead of vacuum signal (like a holley), but either can be tuned to deliver the same results.

[gearheadslife]

Originally Posted by ap72

as does every carb with a vacuum secondary... the edelbrocks and the new demon 625 has secondaries that work off of airspeed instead of vacuum signal (like a holley), but either can be tuned to deliver the same results.

the q-jet small primaries allows better mpg and cruise than you'll EVER
get from a square bore carb