Opinion time:

I am going to replace the Holley 650 on my 350. Its been bored 60 over, 11:1 compression, double humped heads...

What is a better choice, a Mighty Demon or the equivelant Avenger? :confused:

For street, the Avenger would be the one, but with 11:1, I would think that you would opt for more performance, so I would say the Demon.
But if you want a truely 'nice' Holley, check out the 4150 HP series.

great carbs! graemlins/thumbsup.gif

what are your cam specs? The mighty demon is for cams over 240 @ .050 duration id base your decision on that

The Mighty Demon should be a far better performing carb. And it will run great on a motor even if the cam isn't >240 duration @ .050". The 650 Mighty Demon should work awesome for you. Remember BG rates their carbs on a 'wet' flow bench, so the 650 Mighty Demon actually flows much more then the 650 Holley.

-Joe

As I see it the mighty demon is a race carb addpted for the street and the avenger is a performance street carb. The mighty demon is a mechanical secondary, 4 corner idle carb and the avenger is a vacuum secondaty and idles on the primaries.

If you're building a street car to go fast the avenger is a good choice. If you are building a strip car to do street duty the mighty demon is a good choice. Take what I say with some lattitude as everyone's views of what is performance street and what is strip/street is different.

Do looks count? Go with the Demon. Just an opinion.

as dennis said, everyones idea of street or street strip is a little different. that said, if performance is a concern, the demon would win hands down, imo. i would also consider a speed demon, i run one on my 406, and love it. by the way, what is your primary concerns w/ this motor? it seems the two carbs are for quite different applications to me. good luck on the decision

I own a BarryGrant SilverClaw 750 reaction time carb ,take it from me,buy the Holley !!!

Thanks for all the replys. My intent was to install a Mighty Demon, but, my brother-in-law runs an Avenger on his 67 racer. He's stuck on Holley because he says they're easier to adjust. An earlier post asked about specifics on the cam. I bought the car as is. I found the guy that built the engine but he can't remember the specifics on the cam (built in about 1989).

Mighty Demon is probably my choice once my tax refund gets here.

Learning more as I go... thanks for the help

graemlins/beers.gif

Do yourself a big favor Call barry Grant and have them recommend the carb for your application. ASK Them Do yourself another favor and buy the carb they recommend. Once you drive the Demon you won't gp back. As for the Mighty Demon, They recommended a Mighty Demon 650 for my car. Commutes 52 miles a day and has flawless drivabilty. No bogs,hesitations or any hiccups right out of the box. As stated earlier Demons are flow rated wet. Quite different than holley rates their carbs. Ask First and then enjoy it!!

One step ahead of you. Hear's thier response to my email question:

"Tom:

Based on the information you've got we'd recommend using our 650 Mighty Demon P/N 5282010GC, and a dual feed fuel line P/N 140020.


Thank you

Tech"


Let the snow melt and another paycheck or two arrive!!! graemlins/hurray.gif

I don't know. Holleys are good and going from one 650 to another is kinda like spinning your wheels burning up money and not really going anywhere. Any other items for the price of the demon that would add get up and go. Is your suspension gripping the road to apply all your present power? Or get a matching 650 and go dual quad intake for the price of some of those demons :D

I HAD ALMOST THE SAME MOTOR SETUP AND TOOK OFF THE DOUBLE PUMPER HOLLEY AND PUT A VACUME SECONDARY HOLLEY ON IT, WHAT A DIFFERENCE THE MOTOR REACTED SO MUCH BETTER, STREET AND STRIP. TRIAL AND ERROR I BELEIVE. EVERY MOTOR IS DIFFERENT BOTH CARBS WERE 750CFM. JUST MY .02 MIKE :cool: