I have a Mighty demon carb and have been having difficulties getting it to run right with the transferslots only exposed .020 as the insructions say.I added a IDLE-EZE baseplate, which adds a center air-bypass adjustment screw to allow more air in while keeping the throttle plates whre they should be.
Here is my problem, no matter what I do with the idle-eze adjustment screw, my idle remains the same, no increase or decrease in rpm, no sound change no nothing....any ideas why it has no effect?

here is BG's website with info on IDLE-EZE
IDLE-EZE (http://www.barrygrant.com/pages/news.aspx?articleid=IdleEZSolve)

That idle-eeze baseplate sounds like it is the equivalent of the old "drilling the throttle blades" trick for really radical cams. It looks really nice, but you don't have a really radical cam.

Just adjust the idle speed screws to get the idle speed you need. Just make sure you adjust the idle speed screws exactly the same amount so the exact same amount of transfer slot is exposed front and rear.

IMO you don't really need that special base plate.

What idle problems are you trying to fix? Demons are usually on the lean side
at idle and especially part throttle, so by makin a extra "vacuum leak" with the
idle-eze your makin the idle leaner. Have you tried to have more transfer slot
showing? or a smaller idle air bleed, or a bigger idle feed restriction?
Give us more info.

Put your old base plate back on and per the BG instructions set the throttle blades to show .020" of the transfer slot and use the rich lean mixture screws to dial in the idle rpm you are looking for.

Side note: the transfer slot is .020" wide so when you uncover it to look like a square you are set.

The idle mixture screws don't effect the idle speed only the mixture . . . if it idles too low with .020" of slot exposed there's nothing wrong with opening up the throttle blades a little more.

The Demon spec of .020" will get you in the ballpark then tweek idle speed up or down from there.

Whats your intial timing and do you have a vacuum adv? If you have a vacuum adv. is it hooked to manifold or ported vacuum? Timing plays a big role in idle speed and quality.

Originally posted by Eric68:
The idle mixture screws don't effect the idle speed only the mixture . . . if it idles too low with .020" of slot exposed there's nothing wrong with opening up the throttle blades a little more.

The Demon spec of .020" will get you in the ballpark then tweek idle speed up or down from there. Eric - I'm inclined to agree with you but if you read the BG directions it tells you not to adjust the idle screw off the .020" and to use the mixture screws to achieve the desired idle. I helped a friend with a 468 and healthy cam and nothing worked to tame the Mighty demon until we set it back to factory spec's and used the 4 corner mixture screws to find the idle we wanted...

I'm a nut case about balance and things being semetrical so after getting the idle at the rpm we wanted we checked each mixture screw and found the middle ground so they were all adjusted exactally alike. At that point the idle changed a bit and a tweek of the idle screws (about 1/32 to 1/16 of a turn max) brought it back to where we wanted it.

I have gone back to out of the box BG recommended settings each time, only to end up having to open up more throttle plate to get it to idle. If I leave it at .020 it will not allow me to get it to idle higher than 450 rpm, at that point if i push on the accel pump, it kills the engine, telling me it is too rich, also my burning eyes and throught tell me how rich it is running along with my wet plugs.

I have not changed any bleeds or IFR's.I also am not running the vacuum advance, I hooked it up once and it pings under acceleration. As far as the baseplate, I can leave it on, I just have the idle-eze screw closed.

What is your initial timing set at? Sounds to me like that needs to come up.

[ 06-15-2004, 08:32 PM: Message edited by: Novaguy73 ]

Where were your rich lean mixture screws set at? If you can't get it to lean out at idle by closing down all 4 idle mixture screws there is something wrong. How much initial timing are you running? With the duration (more than I thought 240/246@050) of your cam you might need 18degs or so initial. Also make sure your floats are adjusted properly. BG's are the center of the sight opening, not at the bottom like a holley.

My timing is 16* initial, idle mixtures are at 3/4 turn out.

More initial timing might help with the idle speed. If you have the MSD just swap in the black (largest) bushing, use the two medium springs (blue I think), and see where the idle winds up. The slightly heavier blue springs should help with the pinging and have your curve all in by about 3,000 RPMs (instead of 2400-2600 like the light and medium spring combo). Just refer to chart in the MSD instructions to confirm the right spring setup.

I know what you mean about the directions Dennis -- I personally think the Demon directions are a little misleading in this regard. True, you can get the idle speed to change by changing the AF mix, but IMO you should set the AF mix for max vacuum - not idle speed.

I think the point they are trying to make in the Demon video is that the exact same amount of transfer slot should be exposed front and rear. As long as you keep the exact same amount of transfer slot exposed front/rear you will be OK (within reason); after all, a Demon transfer slot is the same as a Holley transfer slot -- it's the same principle. The odd part is the 4 corner idle which requires one to be a little fanatical about front-to-rear and side-to-side balance like me and you ;)

PS. There is a blurb in the Demon video about modifying the low speed air bleeds for an excessively rich idle. This may be something to look into if you just can't quite get it to idle right.