I am installing a new Mallory distributor in my rebuilt 300. I have seen 2 methods for this procedure, which is best?
1- Set #1 piston to 0 degrees top dead center on the compression stroke, and install the distributor so that the rotor points directly too the #1 spark plug terminal. Then time the engine with a timing light during cam break in.
2- Set the #1 piston to between 10 & 14 degrees before top dead centre on the compression stroke (using the timing marks on the harmonic balancer), and install distributor so that the rotor points directly at #1 spark plug terminal. Then check & fine tune the timing during or after cam break in.
Mallory told me to use method #1, as method #2 will not work, but I have seen meathod #2 used on other engines.
Do you also need to line up the stator inside the distributor? I'm not familiar with the Mallory unit, so I don't know if it has one.
On the stock unit, you have to be absolutely certain that an arm on the stator is lined up perfectly between two alignment marks on the magnetic pickup. Each 1/4" off is like 7 - 10 degrees off timing or something.
I've used Method #2 before and it worked flawlessly. Again, on a stock Duraspark II unit.