That’s too much total advance
In the October issue Mr. Childs of Montana had a question regarding total ignition advance; my question is similar. I bought a new Bill Mitchell 351 block Ford street/strip 427 cid/525 hp crate engine to put in my 1993 Ford SVT Lightning pickup truck with a TKO 600 5-speed transmission.
To ease its installation I removed the intake manifold and the MSD distributor. I found that the distributor is locked down at a 30-degree total advance. No vacuum advance or mechanical advance. I called someone at Mitchell engines and they said the engine would start easily locked at 30 degrees’ advance.
This seems like a very high load for the starter to turn this 10:1 comp engine over cold or hot with this much advance. It has no choke on the 1050 CFM Holley carburetor so I know this will take the 3-foot dance on a cold start.
I would like your opinion on installing a 20-degree electronic retard that MSD makes or should I install the mechanical advance back in the distributor with one light spring and a stretched second light spring and have someone reset the mechanical advance to 28-30 degrees advance total, all in at about 1500 rpm.
You definitely do not want to use a distributor with 30 degrees of advance at all times. That is way too much advance during your start-up and at the lower engine speeds.
According to the specs for the 427/525 Ford engine you have, as published on theBill Mitchell Hardcore Racing Products Web site (theengineshop.com), the engine is fitted with an MSD Pro-Billet Ready-To-Run distributor. This particular distributor features MSD’s adjustable mechanical advance, which allows the ignition curve to be adjusted to suit the characteristics of the particular engine. Some of these MSD distributors can also be fitted with a vacuum advance for additional control.
You should install MSD’s adjustable mechanical advance and tailor the advance curve in accordance with the recommendations of the manufacturer of the camshaft that’s in the engine.