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Discussion Starter · #1 ·
having a tough time deciding on which carb i wanna run with.

its a toss up between the 650 speed demon and the 650 mighty demon, both vac. secondaries. I'm leaning more towards the speeddemon for the cheaper price

here are the specs on the drivetrain currently:

355ci
10:1 Compression Ratio
Holley systemaxII alum. heads
Comp cams 270H magnum
Holley street dominator intake
MSD Pro-Billet distributor #8361
MSD Blaster2 Coil
MSD 6AL Ignition box
Edelbrock Thunder Series 650cfm AVS carb
Aeromotive Billet Fuel Pressure Regulator
shortie headers
K&N 4" Open Element air filter

3.73 gears
Eaton Limited-Slip Diff.

Th350 transmission
2800 stall torque conveter
B&M Stacked plate trans cooler
trans-go transpack
 

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Technical Support Barry Grant
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ocbaud said:
having a tough time deciding on which carb i wanna run with.

its a toss up between the 650 speed demon and the 650 mighty demon, both vac. secondaries. I'm leaning more towards the speeddemon for the cheaper price

here are the specs on the drivetrain currently:

355ci
10:1 Compression Ratio
Holley systemaxII alum. heads
Comp cams 270H magnum
Holley street dominator intake
MSD Pro-Billet distributor #8361
MSD Blaster2 Coil
MSD 6AL Ignition box
Edelbrock Thunder Series 650cfm AVS carb
Aeromotive Billet Fuel Pressure Regulator
shortie headers
K&N 4" Open Element air filter

3.73 gears
Eaton Limited-Slip Diff.

Th350 transmission
2800 stall torque conveter
B&M Stacked plate trans cooler
trans-go transpack

On your combination with the cam and intake you're using we'd recommend using the Mighty Demon carburetor. It will give you better tunability, and overall performance.
 

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Dont go with a Demon
i had one and it was nothing but trouble, 500cfm vacuum sec
my boss where i work at said he tried running them on a racecar he built for a customer and he had nothing but problems with them, he said he swapped it out with a 750 holley double pumper and it fixed all his problems


the only thing about Demon carbs is that they are pretty, big whoop :D
 

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Discussion Starter · #7 ·
mynuffinfutsitch said:
Dont go with a Demon
i had one and it was nothing but trouble, 500cfm vacuum sec
my boss where i work at said he tried running them on a racecar he built for a customer and he had nothing but problems with them, he said he swapped it out with a 750 holley double pumper and it fixed all his problems


the only thing about Demon carbs is that they are pretty, big whoop :D

i've heard they are just a pain to tune correctly, but once they are tuned they are awesome carbs.
 

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Discussion Starter · #8 ·
Tech @ BG said:
On your combination with the cam and intake you're using we'd recommend using the Mighty Demon carburetor. It will give you better tunability, and overall performance.

wait.... i was just looking at the bg site and i noticed something. i thought you had a vacuum secondary mighty demon out? also, i see none of them come with any choke?

hmm....


its going in an '86 chevy c10 with a weight of 3950lbs.
 

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Technical Support Barry Grant
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The Vacuum Secondary Mighty Demons are available. They're working on a new website right now, however they should still be listed in the New Products section. None of the Mighty Demon series carburetors have a Choke tower.
 

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Discussion Starter · #10 ·
i'm not sure if i need a choke or not. i mean, the truck is always parked in the garage unless i'm out somewhere with it, and it wont be driven in really cold weather.


how much of a difference would it be performance wise between the mighty and speed demons?
 

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ha, you dont need a choke
i run my old chevy in freezing weather (around 30 degree weather) and all i gotta do is let it warm up for 5 min, as long as it didnt get a big gulp of air (cause it would wanna sneeze) it would run fine i run a 190 degree thermostat
all i did is richen the jets up a hair in the cold
 

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mynuffinfutsitch said:
ha, you dont need a choke
i run my old chevy in freezing weather (around 30 degree weather) and all i gotta do is let it warm up for 5 min, as long as it didnt get a big gulp of air (cause it would wanna sneeze) it would run fine i run a 190 degree thermostat
all i did is richen the jets up a hair in the cold
Match the carb to the application and problems go away.
 

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mynuffinfutsitch said:
Dont go with a Demon
i had one and it was nothing but trouble, 500cfm vacuum sec
my boss where i work at said he tried running them on a racecar he built for a customer and he had nothing but problems with them, he said he swapped it out with a 750 holley double pumper and it fixed all his problems


the only thing about Demon carbs is that they are pretty, big whoop :D

That is illogical.

Blaming a company's entire line

because you had trouble once and your boss didn't know how to tune one. :nono:

Any ill matched carb/combo and any deficiency in tuning is not the fault of the manufacturer.

analogy=
Did you know that on the Firestone tire blow out deal, that the remaining 3 tires on each of the 49 fatal wrecks, the tires averaged 16 psi? Is that Firestone's fault that people run their tires flat? ..... :nono: What a country!!! What ever happened to personal responsibility?
 

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Discussion Starter · #14 ·
alright, looks like i'll get the speed demon carb instead. i'm not paying $200 more for the mighty demon. $615 is kinda pricey for a carb.
 

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By the way, the Firestone verdict for damages and recall was reached because Ford recommended "too low" of a pressure, Firestone knew it and did not refute it. The court was afraid that tires were damaged from running too low of pressure and wanted to prevent further injuries......

neither of which addressed the stupidity of the vehicles' owner's.......duh.

I just read the synopsis.

Liberals Against Common Sense. It should be a new organization. L.A.C.S.
 

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xntrik said:
That is illogical.

Blaming a company's entire line

because you had trouble once and your boss didn't know how to tune one. :nono:

Any ill matched carb/combo and any deficiency in tuning is not the fault of the manufacturer.

analogy=
Did you know that on the Firestone tire blow out deal, that the remaining 3 tires on each of the 49 fatal wrecks, the tires averaged 16 psi? Is that Firestone's fault that people run their tires flat? ..... :nono: What a country!!! What ever happened to personal responsibility?


hahaha he didnt know how to tune one!
its the way the passages are made in the metering block
and how all of them have oversized accelerator pumps

but....
im not saying their entire line is not any good
just stating my opinion man
he can do what he wants, its his money
 

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Technical Support Barry Grant
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ocbaud said:
i'm not sure if i need a choke or not. i mean, the truck is always parked in the garage unless i'm out somewhere with it, and it wont be driven in really cold weather.


how much of a difference would it be performance wise between the mighty and speed demons?

There would be two advantages to the Mighty Demon.
First, it has more adjustments that you can use to fine tune more accurately.
Second, it can handle more radical engine componets, so if you decide to go with a larger camshaft or intake in the future it would work better than a Speed Demon series carburetor.


*** After re-looking at your combination, made a mistake thought your camshaft was more radical than it is. A Speed Demon series carburetor will work extremely well on this combination. You won't see any benifit in performance going to the Mighty Demon series unless you decided to make other engine modifications in the future. ***
 

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Discussion Starter · #18 ·
Tech @ BG said:
*** After re-looking at your combination, made a mistake thought your camshaft was more radical than it is. A Speed Demon series carburetor will work extremely well on this combination. You won't see any benifit in performance going to the Mighty Demon series unless you decided to make other engine modifications in the future. ***
only things that i would possibly change would be to go back to full length headers and i'll be going to a 700r4 with a 3000 stall. ever other major component should stay the same or around there :)
 

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Technical Support Barry Grant
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ocbaud said:
only things that i would possibly change would be to go back to full length headers and i'll be going to a 700r4 with a 3000 stall. ever other major component should stay the same or around there :)

Then you'll be perfect with the Speed Demon. Hey and if you can actually stick to a plan without making changes to the combination you've got more control than most of us do!
 

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Discussion Starter · #20 ·
Tech @ BG said:
Then you'll be perfect with the Speed Demon. Hey and if you can actually stick to a plan without making changes to the combination you've got more control than most of us do!
you still think the vacuum secondary one will be best? This isnt a daily driver, will probably get maybe 4000 miles on it a year. if a mechanical secondary would give me a decent increase in power/performance i wouldn't mind going that if it meant sacrificing a little drivability.

1986 chevy truck
3950lbs
auto tranny
 
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