how many turns to i turn the idle and air mixture on the holly 650DP carb, model # is 4777-s

Dan

 

Start at a turn and a half out and adjust it from there.

 

as is or should i turn it all the way in and then start it of at a turn an a half? cause rite now when the fuems of the exuast goes in my eyes they burn like crazy. i think im runnin to rich

 

As he said, start at a turn and a half out. That means you turn them in until they seat lightly (very lightly, you only want a reference), then back them out 1-1/2 turns. Adjust them equally for max vacuum, warm, in drive, from there.

 

And don't be surprised if your final setting ends up being only 1/4-1/2 turn out from fully seated! The vast majority of Holleys are VERY rich on the idle circuits unless you put them on a very big cube motor.

The main thing is that you want to set them WHERE THEY NEED TO BE, not to some arbitrary spec! Run the engine around the block a few times, get it warmed up and then start leaning out the idle mixture 1/4 turn at a time with the engine running, making sure to adjust evenly side-to-side. Usually the RPMs will pick up slightly as you get down to an ideal setting and then fall off quickly as you go too lean. Back it off into the ideal range again and then maybe 1/4 turn richer than that and you're all set. Don't be surprised if your idle speed picks up some after you do this, requiring you to slow it back down with the idle speed screw. Then do another round on the mixture screws following the same procedure as before and you're all set.