demon tech line good?

[kmarccoco]

in trying to get my demon dialed in, i called the tech line. they told me that they thought that my race demon 850 was most likely to big for my 428. i gave them cam specs ect.

they seemed to be in a hurry and short with me, and i therefore question their opinion.

any carb guys have an opinion on weather my 850 is to big?? thanks.

[jdog]

Hi Ken, sorry I PM'd you before I saw this post!

Have you taken it back to Tom? He should fix it or exchange it for the one you want. I'll see him tomorrow, do you want me to ask him about it?

jdog

[kmarccoco]

i'll be in toms area at about 3:45. i'll drop in and talk to him. see what he says. he been very helpfull after he did my motor. A+ service.

i cant wait to see your car finished.. did he give you an eta on completion???

[jdog]

I hope you mean 15:45 hrs.!

Me too, I'll see you there!

jdog
P.S. We'll check on the ETA tomorrow.

[kmarccoco]

hhahhaa, definately not zero three forty five!!!

[mj_duell]

Originally Posted by kmarccoco

in trying to get my demon dialed in, i called the tech line. they told me that they thought that my race demon 850 was most likely to big for my 428. i gave them cam specs ect.

they seemed to be in a hurry and short with me, and i therefore question their opinion.

any carb guys have an opinion on weather my 850 is to big?? thanks.

Forget the tech line. The guy you want to speak with is Don Gould. He helped me get my Mighty Demon tuned perfect. His company, FBO Systems, blue prints and hops up Barry Grant carbs and races with them as well. Really knows his stuff. Here is their site http://www.4secondsflat.com Try giving him a call.



--Mike / Turn Ten Racing, Inc.

[Zoom This]

Don's the man when it comes to BG carbs. Just bought a Mighty Demon and dialed it in. His step by step manual is great. Comes free with a carb purchase from him or $10 otherwise.

[sllib]

Ken:
I called Demon twice and also talked to a factory rep at the Street Rod Nationals and got the same answer all three times. Because of the duration of my cam I am right in between the Mighty Demon 850 and the Race Demon 750. I opted for the 850, mainly for price, but went with the annular boosters. You might be happier with the Race 750.
Bill Stradtner

[kmarccoco]

thanks for the help. going to try a 750 tomorrow.. will see how it goes....

[decooney]

Ken,
What is it doing wrong, and when does it do it?

At Idle?
Slow Driving?
Under load?
at wide Open Throttle?

From what I recall about your motor as compared to my build, they are not too far off. I run a Holley 830 HP, and it works great - once I got it dialed in. I've wondered how a Daemon 850 would run on my setup but never tried it. With your new muff setup, I don't think your carb is too big, but I could imagine it might need some rework if its stock out of the box.

[Dennis Kelley]

Demon Tech. WHAT A JOKE. There canned answer for all problems is increase your timings.. Question: Theres metal shavings in my CARB. BG TECH "increase you timing" . Good luck your going to need it.

[kmarccoco]

your right on the money dennis.. thats what they said.

hi duane. its hard to pin point the problem. it just seems inconsistant in running well. the passenger side exhaust at idle sounds real good with a nice rhythm to it, and at the same time the drivers side does not. drivers side seems to idle unevenly kinda "runs on" a little . the idle mixture does nothing to correct it. sometimes it stumbles off line, and sometimes it does not. the drivers side pipe will smell rich, and the passenger side wont. sometimes it stumbles when i romp on it at about 2000 rpm, and other times it does not.

i bouhgt the demon carb book, it said that the idle screws should be at least 1 to 1 1/2 turns out for smooth idle. less than one turn out means it has a richness problem and i should go down 2 thousandths in the idle feed restrictors. mine runs best at about 1/2 turn out, indicating that i have a richness problem, at least in the idle circuit. i also punched in my engine info on the link mj duell gave me, "4secondsflat", to calculate cfm for my engine. it spit out 750 cfm carb. the web site also mentioned if carb was to big i could loose h/p and torque. they said with smaller carb/venturi it could max h/p and torque by increasing air velosity... arghhhhh so much to learn with the carb!!!!

any thoughts????

[decooney]

Ken,
I may be off but it sorta sounds like an ignition/firing or plug problem to me. The first thing I'd be doing is reading the plugs on the left bank and comparing to the right and looking for a fouled plug, etc. My guess is it did not run this way in the beginning when you first got the motor together (first few hours) and I'm wondering if one or more of your plugs is so fouled out now that its going bad or is bad. Plug read time. Check the color of those insulators one plug at a time and mark which plug came from which cylinder one by one. Take it out, running full blast and shut off the key close to your house as possible. Coast to a stop, and pull those plugs one by one. Look at the color of those insulators.

Are those the original plugs from when you first ran the motor. All it takes is a few marginal or bad plugs created by an overly rich carb to start with to create your situation. Let us know.

[kmarccoco]

thanks duane.. im bringing it by toms tomorrow....