Quote:



Mild 360 with CompCams XE-268 224 @.050 approx. 10:6:1 compression with box-stock Edelbrock Heads. not sure what the timing is, balancer is marked withe the timing tape, I just need to get a timing light to see exactly where it is. Engine is basically a fairly mild 360 with a good MP convertor and gears. Carb is just VERY rich, more so than it should be, even after re-jetting. Thanks for all the help guys....



Bullit:

OK, for some reason I thought this was a 440 we were discussing. Glad I asked. And you're right, that's a fairly mild cam.

At the risk of explaining something you already know, here's the Reader's Digest condensed version of what I'm thinking: your cam, while mild, still has more valve overlap than a stocker. As such, you have lower cylinder pressure at idle than a stocker. That makes the engine want more initial ignition timing than a stock 360. If the timing is set per stock specifications, you'll probably need to advance it. And when you do, the idle speed will increase, allowing you to back off the curb idle screw, and (I suspect) bring the throttle plates into a much happier relationship with the transfer slots, which has just GOT to help your rich idle condition.

You must, must, must figure out how much ignition timing your engine wants at idle before changing stuff on the carb.

If you have to advance your timing very much to get the idle right, you might end up with too much advance at higher RPM. That's OK, you can deal with that next. Just find how much initial timing makes the engine the happiest at idle and off idle.

You're gonna need a timing light. You've already got a timing tape installed - that's good. You won't need a timing light with dialback.

Shout back if this doesn't make sense. This is basic stuff, and there are lots of people here who can walk you through it.

Jim

Last edited by JimG; 10/18/08 04:38 PM.