Best Way to set the idle mix on a 4160

[patrickt]

OK, I think you are saying that your throttle plates are either not closing evenly, or they are out of whack somehow, or that they are not both even with their respective transition slots. If that is true, they don't really "adjust" all that much, but maybe you have some carbon build-up or something. Now I have heard of carbs that don't have the transfer slots even and that's because of a milling QC issue from Holley. What I would do is follow the "generic" throttle plate instructions that are here: http://www.jegs.com/InstallationInst...-26-93-100.pdf and just clean them up good, maybe do a little filing if they are rough on the edges, and then perform the "light bulb" test. Just get them as smooth as possible and, if the transition slots are not that even, then so be it. Just set the biggest one's opening to a square and leave the other one wherever it lands. Smoothness in the opening and closing is the key though.

EDIT -- Here's a nice thread, with lots of pics, dealing with the joy of throttle plate fixin' on our 4160 carbs: http://www.mastercraft.com/teamtalk/...ad.php?t=54417