Demon carbs

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moparker

moparker

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Thinking of replacing my Holley with a Demon. Never owned one. What are your guys opinion on Demon carbs?
 
Demon was bought out,by Holley.. The product quality was improved,the real question:?!?!?!??? : What is your combination, what you want it to do,& budget?
 
The demon is the same specs as my holley. The float suck on my holley last year and I've heard this is common with them. Thinking I wouldn't have the same worry with the demon.
 
I like and run them. Larger fuel bowls and see thru windows. I've drilled and tapped passages for fine tuning. Out of the box my 650 DP ran rich at highway cruise RPM with a wide band. I had to drop 2 jet sizes on the PMJ, opened the PVCR from .059 to .063, and decreased the MAB from .041 to .028 to cleanup highway cruise.
 
had an 850 on my last 318 - loved it - still have them both and am planning on trying out the Demon on my 360 - because I can.
 
I have a 750 Race Demon on my 64 Sport Fury. Works great. If the float stuck open on your Holley, it's probably dirt in the needle and seat. I use marine filters on my car.
 
Demons =garbage..you want a really good carb get yourself a Quickfuel..
 
I've never had any experience with Demon carbs, but man they sure are good looking carbs...well except for the Street Demons...of course IMHO

mderoy340 said:
I like and run them. Larger fuel bowls and see thru windows. I've drilled and tapped passages for fine tuning. Out of the box my 650 DP ran rich at highway cruise RPM with a wide band. I had to drop 2 jet sizes on the PMJ, opened the PVCR from .059 to .063, and decreased the MAB from .041 to .028 to cleanup highway cruise.
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What's PVCR and MAB? PMJ I'm assuming is Primary Main Jet.
 
moparker said:
Thinking of replacing my Holley with a Demon. Never owned one. What are your guys opinion on Demon carbs?
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They are ok and meter just like holleys and are heavy but very workable and have em on several cars w/great results. I agree that if you want the lightest and best/tuneable billet parts, then the QF or new gen Holley stuff shines but still need tweaks to get the most out of em.............
 
Had a street demon on my 360 - 37 Plym pickup. Out of the box, choke sticking, rear butterflies not closing enough to cover the transfer ports. Maybe assembled on Friday afternoon, or Monday a.m. Adj. fast idle was a pain.
 
JoesEdge said:
I've never had any experience with Demon carbs, but man they sure are good looking carbs...well except for the Street Demons...of course IMHO



What's PVCR and MAB? PMJ I'm assuming is Primary Main Jet.
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PVCR = Power Valve Channel Restrictor
MAB = Main Air Bleed
PMJ = Primary Main Jet
 
stroked340 said:
Demons =garbage..you want a really good carb get yourself a Quickfuel..
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:wack:

Come on man, your comment = garbage. I will explain the why and the how of my statement.

If you want to help anyone with your input tell us WHY Demons are garbage.
Is it a specific model that's crap?
Is it the entire product line?
Is it their customer service?
How about price vs performance?

Same goes for any brand X vs brand Y comparison. Until you back up your statement with data, you're merely full of crap and not worth listening to.
 
I had a 625 Road Demon, worked well, too small for me. Honestly if your Holley is the correct size and type, just buy the better floats and swap them out. If you need a different carb in the form of CFM or dual accelerator pumps, or want a Thermoquad then sure, other wise your just spending money and trading apples for apples.
 
Ottmundr said:
:wack:

Come on man, your comment = garbage. I will explain the why and the how of my statement.

If you want to help anyone with your input tell us WHY Demons are garbage.
Is it a specific model that's crap?
Is it the entire product line?
Is it their customer service?
How about price vs performance?

Same goes for any brand X vs brand Y comparison. Until you back up your statement with data, you're merely full of crap and not worth listening to.
Click to expand...

Because i had a Mighty demon that thing was a piece of ****,no matter what i did to tune that thing nothing would work or when i finally thought i had it dialed-in it would start acting up again,and redo my adjustments again..I highly recommend a Quickfuel right out of the box it has performed flawlessly other then having to change jets for weather conditions..Hows that for an explanation!!!!
 
stroked340 said:
Because i had a Mighty demon that thing was a piece of ****,no matter what i did to tune that thing nothing would work or when i finally thought i had it dialed-in it would start acting up again,and redo my adjustments again..I highly recommend a Quickfuel right out of the box it has performed flawlessly other then having to change jets for weather conditions..Hows that for an explanation!!!!
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....and no other carburetor manufacturer has ever made a bad carburetor.
 
stroked340 said:
The one i had was...and i know more then a few other racers who feel so too...
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I understand. And I know probably an equal amount that have had difficulties with Holley, Quick Fuel and Edelbrock, but that does not mean all from each maker is bad.

With as many carburetors as they all make, it stands to reason some bad ones will get through.

Also, there are probably just as many if not more problems that are operator error.
 
I had a 750 when they first came out. I kept having weird stumble problems no matter what I did. After a while, I talked to their CS rep whom asked me to send it back to them. They sent me a new one and it was one of the most responsive carbs I have ever used. Apparently, some of the very first of their production had problems with the core molds, but had been revised.

I'm actually considering trying one of the Street Demon "Thermoquads" out for my current combo.
 
I just picked up a 750 mighty demon. Rebuilt it with new gaskets and such, looks like a very nice carb!
 
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