Fresh 440 build mild cam (488 lift)452 heads,headers,2600 stall,holly street domonator intake,mighty demon 800 cfm carb.cant get the idle circit right,at idle and warm runs rich and only opening butter flys up leans it out.do i have to much carb or is there something else?I checked vac and its 12in in park,power valve maybe?thanks

I'd call Don over at FBO. He does a lot of work with demon carbs and he would be a good source to tell you what might be wrong or if its too much or too little carb

Mike

Never worked on one of those, but I had almost the same set-up I used a Proformed main body 750DP. I think they rated it at 823cfm. In any event timing is important too. What is your initial and full? I'd think that engine would like 16-18* initail and 36-38* full. 12lbs of vacuum isn't bad but I had mine steady at 14. What is the jetting? Maybe you need to drop it some....floats set?

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