440 Distributor Curve

Tech Question

Fred Joslin, Spokane, WA, 1969 Imperial LeBaron 440

I have the original ignition in this 5000 lb. beast andwant to upgrade to electronic.
I believe that the distributor is good so am I better off getting aPetronix type upgrade for the current distributor or replacing thedistributor with a new one? Most replacement distributors advertise a”performence advance curve”. Will this work OK with the stock torqueconverter and rear end (2.94 I believe)?

Up until 3 or 4 years ago, I would have unquestionably, unhesitantlyrecommended a MP electronic ingition conversion kit. This had the advantageof givving you, effectively, a duplicate of a mid-’70s stock installation,with all the inherent reliabity and ease-of-repair that this implies. And,despite your claim, I’d be surprised if your current distributor’s shaftbushings aren’t worn and the advance weight sticky (or totally stuck.)But…

A few years ago Ma Mopar stopped making these distributors, so they asked MrGasket Co. (Accel, Mallory) to make a clone for MP. The result is, inreality, a way better piece than the original factory one – the casting ismore precise, the bearings are way better, and the advance mechanism is morerealible. And it still looks 100% stock and accepts all stock ‘tune-up’parts. So, what’s the problem, you ask?

Well, for whatever reason, MP specified that the distributor be shipped witha super-fast, race-oriented advance curve. And, exactly as you suspect, withyour stock engine, and, especially, with today’s lousy pump gas, the resultwould be (your choice): Severe knocking, or, if intital timing is retardedenough, no knocking, but lousy performance / driveability.

The fix for this is easy enough, Mallory sells a real nice little kit thatallows you to easily and quickly tailor the curve to your engine’s needs.This was outlined in detail in Mopar Action, December, 2004 issue, as partof the Bold Beeper series.

The Pertronix has a long history of reliabilty also, however, personally, Istill prefer the MP setup. The choice, however, is yours.

Rick