I'm sure alot of you know this, but I didn't, so for the "others like me", I found some interesting thing about CFM rating:
Did you know that most carbs are rated under "dry" flow (just air), which in a way is kinda useless since in a real aplictaion, the carb has to flow air and fuel.
And at last, this regarding Demon carbs, did you know that Demons CFM are rated on a "wet" flow bases in order to get a real number that would correspond as a real environment (of air and fuel that is). This explain why Demons seems BIG, when you swap an 850 holley to an 850 demon. They also recomend to stay below 850 when using less than 460cid....by the way, you can read all this info on the book called "Demons Carburators", which I found at Barnes'n'Nobles...

 

That is interesting. There has been some conjecture on here that Demons are rated differently..but this is the first solid info I've heard on it.

It really kinda strikes a blow against Demon IMO if thats true. The few dyno tests I've seen with them have put them just a couple ponies better than a normal Holley thats cheaper. The extra few cfm would account for that...doesn't mean the carb itself performs any better at all.

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"American made baby. 100% American iron. The muscle among the masses. My hero. Yep, you can take your ergonomically designed, space age, computer controlled, 4 door, cup holding map lighted split double wishbone split fold down retractable cargo covered moon roof piece of transportation and keep it. For I have felt the thunder. And I know the difference!"
JSP Motorsports
ICON Motorsports

 

BTW...750cfm of wet flow is roughly equivilent to 825 of dry.
at least if I remember corectly.

 

were the test done with the same advertised CFM ? What I mean is did they use an 850 holley then and 850 demon for exemple, or did they down sized to a 750 for the demon?
just outta curiousity...
how also do you figure a regular 4150 or 4160 holley are cheaper? hell the street avenger is about the same price, 375 for the 770 and 426 for the 870...375 for an 800 DP, 412 for an 850...440 for a demon and 399 for a VS...kinda same ball park!

 

The street avenger is way overpriced for what you get. Compare it to a regular holley carb. If two carbs are rated at 750 dry flow cfm at the same amount of vacuum and are the same type(square bore)--in other words they flow the same--both will give about the power when tuned to their peak power. A carb can only do so much toward power. Once they get the optimum air/fuel mixture for max power, the brand doesn't matter.

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350 with stealth intake, holley carb, 470 lift cam. 700r4 with .5 boost valve, vette servo, tci lock-up kit, B&M megashifter. Richmond 3.73 gears, powertrax locker, timkin bearings, synthetic lube. Custom 3 inch single into 2 2.5 pipes. 1 1/2 drop springs, 1 5/16 solid front sway bar, 1 inch rear bar, custom subframe connectors, custom LCA relocation brackets. Kobel ground FX, currant red metallic paint. Lots of other stuff...
82camaro


[This message has been edited by 82camaro (edited September 11, 2001).]

 

82camaro thats not really true. If you don't believe me..read this post:

https://www.thirdgen.org/messgboard/...ML/001139.html

 

One example(not very scientific I might add) with some different cfm carbs proves what exactly. A carb mixes air with fuel for the engine to burn, thats all they do.

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350 with stealth intake, holley carb, 470 lift cam. 700r4 with .5 boost valve, vette servo, tci lock-up kit, B&M megashifter. Richmond 3.73 gears, powertrax locker, timkin bearings, synthetic lube. Custom 3 inch single into 2 2.5 pipes. 1 1/2 drop springs, 1 5/16 solid front sway bar, 1 inch rear bar, custom subframe connectors, custom LCA relocation brackets. Kobel ground FX, currant red metallic paint. Lots of other stuff...
82camaro

 

In theory, but different carbs differ at how well they atomize fuel, and how well they distribute the charge to all cylinders.