[Larry Navarro]

i sold my HP1050 this morning, now looking at Demon carbs just for grins.
they have an 850 "mighty demon" with annular boosters and down leg boosters.
two questions.
first, what are your feelings about the demon products?
second, what boosters offer the best performance for street driving and occasional strip use?
skip fix seems to like his demon right out of the box.
skip, what series demon do you run?
thanks guys!


[This message was edited by Larry Navarro on December 28, 2002 at 05:57 PM.]

[Larry Navarro]

i sold my HP1050 this morning, now looking at Demon carbs just for grins.
they have an 850 "mighty demon" with annular boosters and down leg boosters.
two questions.
first, what are your feelings about the demon products?
second, what boosters offer the best performance for street driving and occasional strip use?
skip fix seems to like his demon right out of the box.
skip, what series demon do you run?
thanks guys!


[This message was edited by Larry Navarro on December 28, 2002 at 05:57 PM.]

[WARPed]

I own two (750rs race & 1095rs King) and they are great, both are annular discharge boosters. They will offer a better quality of air/fuel at the price of some airflow.

with out questions there can be no answers

1969 Grand Prix
[email protected](1.358)
[email protected](1.342)
WARPed Tepee Forums
[email protected]

[Tom Vaught]

Any carburetor with annular boosters will have a higher signal to the jets and will use a slightly smaller jet size (like 2 sizes). The demons have
a lot of nice features over the holley like billet metering blocks, large sight glass bowls,
billet throttle bases, and if you get the right carb screw in air bleeds.

The calibration as far as what airbleeds, jets,
emulsion jets, needles and seats, etc is spelled
out very clearly in the DEMON performance book
(info which Holley does not have in printed form
BUT I have never had a tech refuse to tell me
the size of an air bleed or emulsion hole on a
holley. Just more PITA to get the info.

Most Demon will run rich on the street with a normal engine as this is SAFE for Demon to sell.
Some rejetting will be required anyway on any
carb. Jim Hand had to take a couple of jet sizes out of Patrick James carb from Pro Systems.
Tom V.

[Skip Fix]

Larry, Mine is an 850cfm downleg boosters(talk to 5 different Holley or Grant tech guys and they all seem to disagree which booster and size is the best for a heavy car with my motor).They changed the names(Speed Demon, Road Demon??) now but is is the one around $450. Not the high dollar one with changeable sleeves and boosters. I think I look at it as too many variables(bleeds, boosters) are too many things I can screw up! Maybe if you know what you are doing on the dyno with a BSFC measurment you can really dial it in
.
It was almost right on out of the box. Idles great. Ran faster than my 800+ cfm Carb Shop prepped Q jet even using an adapter plate to put in on the HO intake.I did have to add secondary jet extensions and fatten it up 2 jet sizes.When running no air cleaner and open headers. That lean pop doing a dry hop at night out the scoop got my attention!No choke on mine but it seems to run OK without it.
I love the glass sight for the level on the side so I don't have to get gas all over. Those clear Moroso ones on my Holley's would get cloudy to quick

[SCOTT ESTERLE]

Call Scott Witmer at Demon ext 131 off the top of my head & tell him i sent you he will hook you up with the right one.

[Bad-Goat]

Who makes the Demon, dose anyone have the phone number?

[Larry Navarro]

demon users...i've read where the demon requires a special line kit. [img]/infopop/emoticons/icon_confused.gif[/img]
won't regular holley type AN fittings for fuel line connections work on the demon carbs?
thanks!

[head #96]

No, the Holley uses different size fuel bowl fittings. I use two felxible lines off the regulator for my Demon [img]/infopop/emoticons/icon_wink.gif[/img]

[Skip Fix]

Larry, If you have a Holley AN line you can just buy the AN fittings for the Demon. Different thread size. I may even have an extra one or two.
I got mine from Summit.

[Tom Vaught]

Larry,

Barry Grant makes the Demon.

The mighty Demon is a good carb and should serve you well as it has adjustable air bleeds and the
annular boosters you mentioned along with screw
in emulsion tube bleeds. Tom V.

[455-4+1]

Recently purchased an 850 Mighty Demon anular discharge for my street/strip TA

Features are great over the old Holley but a few problems encountered at startup

Machining swarf in the secondary needle and seat causing flooding when pump first turned on and secondary squirter hole burred over and mostly blocked causing reduced pump shot.

Thought quality control and supposid "wet flow testing" of each carb should be better for $1500
(what they cost here in NZ)

Carb had a slight flat spot just off idle (std pink cam and 031 shooter) change to a green cam seemed to sort things out (more lift per throttle opening earlier) pink cam seemed a little "lazy" at loading the shooter straight off idle.

Whatch pressed in booster rings on annular discharge models. After one meeting one came loose!!!!! and almost worked its way right out

Am sure my engine would have loved ingesting that!! [img]/infopop/emoticons/icon_mad.gif[/img]

Appart from that no problems so far

Working on going faster!!!

[Tom Vaught]

Quote from 455 4+1:

"Machining swarf in the secondary needle and seat causing flooding when pump first turned on and secondary squirter hole burred over and mostly blocked causing reduced pump shot.

Thought quality control and supposid "wet flow testing" of each carb should be better for $1500
(what they cost here in NZ)


Unfortunately, ***** happens, (it seems like more often with the DEMON stuff than other carb builders but they are more of a production shop now). No excuse for the machining pieces but several of our members in the local area had the
same contamination. The squirter deal I think is
more uncommon.

Quote:

"Carb had a slight flat spot just off idle (std pink cam and 031 shooter) change to a green cam seemed to sort things out (more lift per throttle opening earlier) pink cam seemed a little "lazy" at loading the shooter straight off idle."


This is more of a tuning suggestion than a carb
complaint. Tuning of pump shot is vehicle/engine
specific.

Quote:

"Whatch pressed in booster rings on annular discharge models. After one meeting one came loose!!!!! and almost worked its way right out.

Am sure my engine would have loved ingesting that!!"


I buy the Holley annular booster pieces and you
have to use a vice normally to press them together. Once they are together, it is extremely
hard to get them apart. Apparently Barry Grant did not use the same specs on his stuff. You
would have a really bad day if one came out, but
this is true of any Holley or Grant style booster
vs an AFB or Rochester booster (2bbl) which can't come out. Tom V.

[Larry Navarro]

okay, the mighty demon 850 is on the way.
thanks for the help scott e.!

[pont406]

Anyone changing from a Holley carb, to a Demon Carb,(like I did) and using one of those chrome steel dual fuel line setups, holley makes the proper bowl fittings for the swap, part no# 26-43 if memory serves.

[455-4+1]

Tom

Comments posted were for information purposes to highlight possible problems not intended as a complaint.The booster problem was highlighted so two piece annular boosters could be check prior to installing the carb possibly saving someone an engine. One of my inner bosster rings had no interference fit with the main booster body as stated. It can be removed by placing your finger in the booster ring and pulling it out (scar y)

I totally agree on the shooter/cam thing. No general purpose carb can taylor for all engine chassis combinations out of the box. The inforamation was provided as previous topics/posts had discussed upsizing primary shooter size on these carbs. Not a complaint just some general information specific to my combo

Any ideas on fixing the sloppy booster insert ????

As for the quality control I thought 3 faults on a "wet tested" new carb was a little rough so I guess this was a bit of a bitch on my part (although I still feel it justified) Maybe my unit was just a Friday afternoon one non typical of the batch. As you stated "**** happens"

The "carburetor flow card" attached certified that idle flow, wot flow, leak check, tip in/full range, primary and secondary squirter (employee #77 must have had his/her eyes closed for that one , and float level were all checked. Mind you the flow card was just a photocopy of a filled in check sheet so maybe not all are tested or the Friday afternoon thing came into play. Who knows

As stated in my first post its still a good unit and I was just posting my findings and experiences as asked

Working on going faster!!!

[ponchopete]

Not trying to be argumentative with anyone here, just some observations on Demon carbs that I've had since I work for a speed shop which has been selling these carbs for a couple of years:

-literally every customer that I have sold a Demon to has had problems with an off idle stumble that has proven to be difficult at best to tune, even with the help of B/G technicians
-many Demon carbs seem to have very unresponsive idle circuit tuning
-at least 30-40% of the carbs I have sold have had metal particles in them that appear to be left over from machining processes
-several have had loose power valves right out of the box
-A reputable local performance oriented tuning facility that is equipped with a chassis dyno has repeatedly reported that the fuel curves of various Demon carbs they've tried to tune are all over the place, and have in almost every case replaced the Demon carbs with Holley HP carbs, which have consistently shown stable fuel curves along with horsepower and torque increases on every vehicle they have switched over.
-A reputable local engine builder who offers many high horsepower turn key engines had a customer's 500 h.p. pump gas small blah Chevy on the dyno. The engine was equipped with a 750 cfm Speed Demon with mechanical secondaries. After optimizing the tune on the Demon for max power production, they then installed a Holley 750 double pumper (#0-4779) with choke and all just for comparison. In out of the box tune on the Holley, the engine picked up 17 horsepower at peak on the very next pull, and the gain was repeated on the second pull with the Holley. The Demon was reinstalled, and horsepower promptly dropped.

Personally, I am not impressed with these carburetors. There are some very nice ideas behind the Demon line of carburetors, but I think the execution of the final product is poor, especially for the money the customer has to spend on one of these. For those that have had success with them, great, but I myself will stick with Holley. Just as FYI, the thread size in Demon float bowls is 9/16"-24 (same as a Holley 1850). Just about all of the major AN fitting suppliers have fittings that will work in these bowls.

"My car would be fast if it had an engine, transmission, and rear axle in it."

[T-Mac]

One of the Summit salesmen (Sparks store) had called me yesterday regarding an item I had ordered.

While on the phone with him we ended up chatting for a while.
When the discussion got around to carburetors he stated that he had tried a demon carb on his big block chevelle.
The car would blow black smoke all the time, like a stuck float and would not respond to tuning efforts. Even 5 jet sizes had no effect.
He exchanged it two times but all three did the same thing.
He returned the demon and purchased a Holley and his car is running very well with it.

Seems some people have very good luck with them and other people don't.

[This message was edited by Todd McClatchie on January 01, 2003 at 05:43 AM.]

[SCOTT ESTERLE]

When you buy a Demon you have to make sure you buy one that is set-up for your cam specs at .050 duration. A normal 750 Demon will not work if your cam has more than .240 duration at .050 it will run very rich do to the way the carb has been set-up. Demon has a chart that shows what carbs will work with what engines & cam profiles. So if your on the border you may want to go with the next bigger one they reccomend. Thanks Larry. Scott

[Larry Navarro]

geez...what next.
hope my demon wasn't built on friday.
hopefully, they corrected the past problems with the new "mighty" demon line.