I just ran my new carb for the first time yesterday. Its a Mighty Demon 850 on a single plain Victor intake on my 455. I read through the manual to make sure the initial setup was correct before i installed it. Bolted up and went to the river. It ran great, i was really pleased. Picked up 100 rpms over my old setup with tunnel ram and dual edelbrock 600's. However, i can't seem to get it to idle down. I like my boat to idle at 1000 rpm's. Its idling at 1200. The Demon carb has a butterfly adjustment screw on the primary and secondary butterflies. I adjusted the one on the primary and it did not have an effect on idle speed. I could not slow the idle down. In the manual, they stessed several times that the butterfly position is really important or else and off idel stumble could occur. So how do i fix this?
Also, at wot, i saw 4800 rpms, then if i let off the throttle just a hair, the rpms would go up to 4900. Whats up with that?
Kevin