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!
http://store.summitracing.com/global...-5563020gc.jpg

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

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!
http://store.summitracing.com/global...-5563020gc.jpg

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

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]

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.

http://kurtsplates.homestead.com/files/UR2SLO.jpg

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

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.

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

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!

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]

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.

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.

http://kurtsplates.homestead.com/files/UR2SLO.jpg

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!!!

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.

http://kurtsplates.homestead.com/files/UR2SLO.jpg

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

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.

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 http://forums.performanceyears.com/g...s/icon_eek.gify)

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 http://forums.performanceyears.com/g.../icon_wink.gif, 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!!!

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. http://forums.performanceyears.com/g...icon_smile.gif

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

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.]

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

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

I have a 750 no choke Speed Demon on my mild 406. I have not taken the car back to the track with this car, but on the street I also experience a slight stumble off idle. It seems to do it when the temp. is under 160 in the engine. Is this because of the no choke?(TOM?)I like this carb otherwise. I had a 700 holley for 10 years which now needs to be rebuilt. I switched over to a 750 vacumn Holley (I know, don't bash me too hard I've always had mechanical secondaries till now) and had problems with that carb from day one. In defense of the Holley, I never made a serious effort to tune the secondary opening spring. I bought the Demon after seeing some dyno pulls of a friend with a Holley and Demon. His Demon made about 10 hp diff. I don't know if there were tuning issues here or not, but I saw the results. Time will tell in the spring if this carb is what I'm looking for.I know the Richcreeks (Herdsclan) had problems with theirs by talking to Tom and Amy at Milan at a Royal Pontiac Race Day. I will say that out of the box, the carb makes the engine sound better and the jetting seems to be pretty close (a little rich) by the look of the plugs, but then again the car was idleing a lot and I have'nt had a chance to really blow it out. Just my .02 cents http://forums.performanceyears.com/g.../icon_cool.gif http://forums.performanceyears.com/g.../icon_cool.gif

The slight hesitation when cold could be either lack of choke (Choke makes the fuel curve rich), not quite enough idle feed restriction size for no choke, or you need a slightly larger shooter/
longer duration pump shot to get past the tip-in hesitation.

I would not have brought up Amy and Tom"s Demon
carb normally. There was a LOT of swearing going on on that carb over a few months. Tom finally got a new one and gave it to me out of the box. The new one was not right either. (contamination in the bowls, loose power valve, and here is the big kicker. wrong mainbody to base gasket). I put
the right gasket on the main body and the 4 corner
idle suddenly worked. This was supposed to be a
carb that the line production manager PERSONALLY
built for Tom due to all of the problem. BS! BS!
BS!

Tom eventually sold the carb to Bud Lyons after I worked on it and Bud says it worked great with a
jet change for his motor and slight tweaking.

Tom V.

http://kurtsplates.homestead.com/files/UR2SLO.jpg

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> 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.
<HR></BLOCKQUOTE>
one comforting quote, as i'm trying to keep an optimistic look through the entire series of posts. should have my carb tomorrow(second day air).

Larry,

Have seen SEVERAL Mighty Demons used on Blower
carb Magazine articles and all say no issues.
Expensive carb though. Tom V.

http://kurtsplates.homestead.com/files/UR2SLO.jpg

I fattend up the secondrys, bolted it on and let it rip. I have not had a chance to take the car to the track yet but it feels like it pulls harder then the Qjet I had on it.

http://kurtsplates.homestead.com/files/budgto.jpg

My Rig's a little old, but that don't mean she's slow.

Tom, go ahead and bring it up. That carb had some VERY serious quality control issues and the management at Barry Grant failed to recognize that fact. Basically told us they'd send us a new carb but to not call them again. Took the new carb and it ran like crap. So we never called them, my husband looked it over, we sent it to you for a complete tear-down, you found the multiple problems with it and Barry Grant's people can just read about it on the 'net. Don't think they'll be seeing any more of our money for awhile. http://forums.performanceyears.com/g...s/icon_mad.gif

Ponchopete, while I'm sorry that your customers have had troubles with their Demons, it's nice to know that it's not just us. Seems like the people we'd heard about that had Demons were very happy with them, no problems. Was beginning to think that we had some dark cloud following us around. Now runnning a $75 POS swap-meet Holley and it runs like a champ. http://forums.performanceyears.com/g.../icon_wink.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by herdswoman:
That carb had some VERY serious quality control issues<HR></BLOCKQUOTE>

I had some quality issues as well with my BG!
Had a real hard time tuning right out of the box, tore it down and found metal turnings in both primary and secondary metering blocks.
A friend of mine had the same tuning problems and found the same thing, turnings in the metering blocks!
Not what I would expect from a $600 carb!

Also heard that Jegs pulled the fuel pump line from thier catalog due to quality problems!

MOTOR CITIES FINEST
PHS Documented "REAL JUDGE"
12.53 @ 110.68 on street tires, through the mufflers and a 4 speed!!

Sounds like how my Q jet came back from the Carb Shop years ago, metal shavings in the bowl.And that was even when Brad Urban was still there.

I have always stayed away from the BG/Demon carbs as I always thought they were just over priced Holley copies. In fact there was a large law suite between Barry Grant and Holley. As a result BG had to do some design changes, mostly cosmetic to settle the suite. I disagree with the judges decision. At first BG was just tuning/modifying the Holley carbs (like the carb shop does) and as the business grew started making Holley copies then the law suite. You would think that for the money they charge for a Holley copy they would have better quality control. Some people are attracted to the Demon carbs because they are new and advertising has convinced them they are better than a Holley. So far I am not convinced http://forums.performanceyears.com/g.../icon_razz.gif

Tim C

65 LeMans, 3600lb. all steel, full interior, D-ports and a flat tappet cam, 11.01@120

received my demon yesterday.
very nice piece. included were an instructional video(whoopdedo) and "owners manual".
hate to tear into a new carb, but i sure do want to check for all the said, abnormalities.

Larry , They do have the good no stick gaskets so it comes apart easily. If your car is going to hook hard I would recommend getting the jet extenesions for the secondaries, the kind the jets screw into. As it hooks gas sloshes to rear away form metering block.You have to get a notched float also.Not sure if you ordered yours with them. Not a problem with Q jets with jets at the bottom of the bowl.

While you are working on the rear of the carb that you just paid big bucks for, check and see
if the mighty demon has a rear power valve for me.

If it does, take it out on your drag car, Larry.
Put a plug in and go up on the jet sizes on the rear about 8 numbers. The power valve if left in will suck air long before the jets without extensions will. Good luck. Hopefully no trash
in your new carb. Tom V.

http://kurtsplates.homestead.com/files/UR2SLO.jpg

Herdswoman, Tim C., All-Ryze,
In my not so humble opinion, B/G products are simply crap. B/G technical support fits the bill well, as it is crap too. The fuel pump problem most definitely exists. In the last six months, we have had numerous complaints and problems with their fuel pumps. They have one of the worst warranty policies in the business -- you have to send your part back, they fix it, and charge you for any parts they used, even if the problem is a manufacturer defect. They will not sell repair parts for their pumps or regulators to their dealers or the end user. We recently sent back a 280 pump, as it was leaking from between the motor and housing. They repaired it, and sent a repair bill for $234.00. We sell these pumps new for $289.00! Just in case anybody needs parts for their B/G stuff, and don't want the hassle of dealing with them, I believe Product Engineering has service parts that will work in the B/G junk.
As far as the Holley lawsuit goes, to the best of my understanding, that whole deal is the reason the Demon line of carburetors came to be. Originally, along with their modified carburetors, B/G offered the "Claw" series of carburetors (SportClaw, SilverClaw, GoldClaw), which had all the same features that the Demons have now (Speed Demon, Race Demon, Race Demon RS). The Claw series used all B/G manufactured parts, but looked almost identical to a Holley. I'm told that this is what sparked the lawsuit, which, IMO, Holley was well within their right to do. Supposedly, to make Holley happy, B/G agreed to drop the Claw line of carbs and go back to the drawing boards, which produced the Demon. It's funny, because the Claw series of carbs seemed to work extremely well. The Demon carbs have had problems since day one. http://forums.performanceyears.com/g...s/icon_eek.gif

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

Tom

My 850 Annular Mighty Demon has provision for a secondary power valve but comes plugged (as all cars that leave resonably should do as you stated)

Jetting std is 80 up front and 88 rear so jetting is staggered to account for PV

Anyone out there have a 750 VS Speed demon

Was working on one today for a friend on a (gasp) 360 mopar and the secondaries would open when "winging" the throttle in neutral with a brown (heavy) spring in it. (accompanied by a bad midrange bog)

My previous experience with Holleys lead me to think maybe the check ball in the vacum pod had been left out. Upon dissassembly there was no check ball-slot nor the later style pressed in brass restriction with a drilled hole (0.038" on the old Holley one sitting in front of me). The passage is around 1/4" in diameter?????.

They (BG) also state the exact starting opening points and full open points as the holley VS models for the different spring colours which is fine except that the installed height of the springs is some 4mm greater in the Demon causing the spring to be preloaded less ????? (ie Earlier opening point)

Unable to figure out how this could be I emailed BG and got a one line reply stating "based on the orifice size going through the main body we do not use a check ball in our vacuum pods." yet the pick up in the main body looks the same as in the old 750 Holley the demon replaced!!! The Holley uses a checkball-slot and runs like a cut cat with a yellow (light) spring

If anyone has a VS demon that runs well http://forums.performanceyears.com/g...s/icon_eek.gifcould they please check if it has a pressed in brass restrictor in the vacum passage in the main body of the vacum pod like the old Holleys

Thanks in advance

Working on going faster!!!

I deal with Barry Grant almost on a daily bases being i work in the warranty dept. I don't have much of an issue with them. It might be they take care of us & our cust do to the large volume we sell of there products. The reason they want to handle the warr is do to the carbs are pretty much a custom piece even though you can get them off the shelf. We were testing rtned carbs at Summit & over a 6month period we found that very few had a problem it was generally installation error. When a company gets a product back that isn't defective why should they eat it because they certaintly can't re-sell it as new.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by ponchopete:
It's funny, because the Claw series of carbs seemed to work extremely well<HR></BLOCKQUOTE>

Poncho,
The problems I was refering to were on the silver claws. 2 claws, both with metal turnings!
Once clean, they tuned real well, kind of like a Holley! http://forums.performanceyears.com/g...n_rolleyes.gif

MOTOR CITIES FINEST
PHS Documented "REAL JUDGE"
12.53 @ 110.68 on street tires, through the mufflers and a 4 speed!!

Quote:

"It's funny, because the Claw series of carbs seemed to work extremely well. The Demon carbs have had problems since day one."

Holley made a LOT of money off of Mr. Grant for his "extreme resemblance" of the Claw carbs to
the Holley carbs. He thought they looked different
enough but a group of 12 people thought a little
"differently" LOL!

As the claws were based on exactly the same design
calibration specs, you would hope that the homework Holley did would translate to the claw
piece of metal and work well too.

Scott, because he works for Summit is caught in the middle.

My opinion, NO CARB should have trash inside it!
Be it Weber, Rochester, Holley, Demon, etc.

Hard for Owner installation to get metal shavings inside a carb. Scott. Tom V.

http://kurtsplates.homestead.com/files/UR2SLO.jpg

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Larry Navarro:
received my demon yesterday.
very nice piece. included were an instructional video(whoopdedo) <HR></BLOCKQUOTE>

Larry, hang on to that video. It is most useful on sleepless nights. Zzzzzzzzzz........

Scott E., that's exactly the kind of thing I was talking about....Summit with their high volume has seen very few problems with the Demons they sell and to the best of my knowledge, neither have the guys at KRE. Makes me wonder what it really going on down there in Ga. http://forums.performanceyears.com/g...n_confused.gif http://forums.performanceyears.com/g...n_rolleyes.gif True enough, BG cannot sell returned merchandise as new. But in our case, they shouldn't have sold it in the first place. We put a lot of time and money into ours to make it as it should have been when it came off the production line.

Once again, Tom V. is right. Kinda hard for installation error to get those metal shavings (or the wrong gasket) inside. Gotta wonder though, Tom , would have described those gaskets as no-stick and easy to remove?

I get so warm and fuzzy inside just reading this, I have half a mind to forward this thread to those fine folks in Georgia.. http://forums.performanceyears.com/g...s/icon_mad.gif

[This message was edited by herdswoman on January 04, 2003 at 06:13 PM.]

I agree there should not be any metal shavings in the carb. You are paying top dollar that thing should perform out of the box. Holley is not flawless i just took one of there new carbs apart Friday & it was full of silver particles from that nice silver finish they put on the carb. What i suggest is just like the oil pumps take it apart & check the float settings & everything before you run it. That is what i do.

took the carb apart this evening and found nothing, no shavings or any other problems.
seems like a very well prepared piece out of the box. the secondary block has a plug for the pwr valve and the jetting is 80pri. and 88sec.
bad thing is that i don't have time to put it to use on the car, maybe not till next weekend.
business and related travel are gonna keep me occupied for a while.

My 850 with the down legs came with 83 and 90s.Probably a little different bleeds also.

The 750 Drag Race Demon I bought through Butler had machine turnings in it as well. BG's QC Dept. needs to get with it.

http://home.earthlink.net/~uptons1/_...censeplate.jpg
http://home.earthlink.net/~uptons1/

Glad you got a clean carb Larry, Let us know how it works. Tom V.

http://kurtsplates.homestead.com/files/UR2SLO.jpg

Tom

What are your thoughts on the vacum signal for the secondaries with no restriction mentioned in my earlier post in this topic (750 VS speed demon) and the different installed heights of the springs????

I am sure with your previous experience with Holley you may have some ideas and maybe could shed some light on the restrictions used in the Holley carbs to restrict?? the signal seen by the vacum pod??

Any help would be much appreciated http://forums.performanceyears.com/g...icon_smile.gif

Working on going faster!!!