 Re: Help with Ignition Timing on Ford 392
Posman,
The important thing is that you initally set your 'Total' timing of 32° as described at 4000RPM. Then you can adjust your idle speed, this will vary from motor to motor and is dependant on cam, carb, exhaust, compression ratio, flywheel weight etc etc. The mechanical advance curve in your distributor is controlled by the weights/springs fitted. In your case you may have a 10° advance plate fitted which would mean that your base timing should be 12° BTDC ( [10° x 2]+12° =32° ). Now dependant on the spring strength you may not be able to obtain a low enough idle speed to give a constant base timing figure to check timing with, so if you check @ 4000 RPM for 32° and then check at idle to ensure your weight mechanism is functioning correctly you will have all bases covered. You can alter the advance curve of the distributor by means of different springs to help the driveability of the car at lower RPM once you get the basics sorted.
The figures I have given above are a guess on my part-but its a pretty good guess!
Jac Mac |