otis_lee

Does anyone have a rough idea about the appropriate idle speed (rpm's) for a 351w with a heavy cam?
Thanks a lot.

sixt5

theres not going to be a definate answer. if you can get it going, play with it. see how it drives

1970coupe

whatever sounds goood.

BULLITT GT 390

650 to 800 some where in there isa good idle speed

otis_lee

I traded this car off a friend. In order to keep the thing from stalling in park...or when I shift into drive/reverse from park, I am having to crank up the idle to above 1100rpm. It just seems way too high. Maybe this motor doesn't care for the heavy cam. It's a 68 body.

sixt5

what are you calling a heavy cam? got some specs? for one person, a 600 lift is a heavy cam. try having a car idle at 2 grand and redline around 7500. BIG cam

69thunder

If it has a large cam idle in park will be high. Just a fact of life with a big cam.

USMCrebel

your idle with a 351w sound be no more than 900.....and the car not dying in park and idle is a problem older cars had, my uncles 53 ford, my grandad's 68 chevy all had the same problem.

urban_cowboy

The optimum idle speed is going to be a function of the carb and the cam. There are a bunch of articles on how to set the idle and jetting per manifold vacuum. It is really going to be different for evey car. A 230/230 .600 lift cam with a 700cfm carb may need to idle around 900-1000, but it is really a custom thing. The goal with any idle setting is a "lean-best" setting - that is, the leanest possible ratio yeilds the maximum idle vacuum while maintaining the rpm set point. Basicly, you should set the idle mixture so that the vacuum is the highest it can and the idle speed as low as it can and still let the engine run. Here is a pretty good article on the process.

http://www.fordmuscle.com/archives/2...ockCarburetor/

otis_lee

The cam has a little under .6 lift. It may be that I need to be happy with a high idle. I just hate that the auto 3 speed shifts into 2nd without me even punching the gas. It sure does a number on the brakes, too. ...And I am planning on fine tuning the carb. Just waiting for my new tach/dwell to come in.
I really appreciate the input...do any of you thinkthat the need for high idle speed (to avoid stalling at idle)could be due to the improper positioning of the manual choke? I just have it stuck wide open.
Thanks again.