Packard Forum Index » Post-War (1946-54)

G'day Equinox,
to PackardInfo.

And I invite you to include your Packard/s in the Packard Owner's Registry.

If it helps you, Champion J-8 crosses to an Autolite 295 and an AC 45; give them a try if you wish but I've found them to be generally too cold for Packards using the 14mm plug. Autolite's specific recommendation is for the 308, pretty much the equivalent of AC 46 and Champion J-11. Packard's specification for you car was a Champion J-8.

If most of your driving will be a fairly regular diet of higher speed touring perhaps the colder plug would be the better choice but generally collector cars see a routine of more stop-and-go and lower speed operation. Perhaps consideration of how you intend to use your car will help with your choice.

53 Packard:
Just out of curisoity, where did u get the AC Delco LM49 sparking plugs??

Additional comment regarding using spark plugs with longer threads...if there are any threads sticking down into the combustion chamber then those threads are very thin and will get very hot and will most likely begin to glow red hot and cause pre-ignition and pinging.

"On my plug conversion chart, Autolite #308 corresponds to NGK B2. That is very hot.
Might owners of 51-54 models comment here on what plugs they have in their cars?"


I have a 51/288 and a 53/327 I have used the Champ J-8 and the Champ J-11 in both engines. I was not able to discern any quantifiable difference between the two heat ranges. So I stuck with the J-8 as recommended by the Packard Service Specs.
Regards.

I'm using the AC-R45 (still generally available) in my '54 327 and it runs like a Dickensian Orphan.

I am also using non-resistor Packard 440 wire with it.

Equinox,
for including your '54 Clipper Deluxe Sportster in the Registry.

My '54 Convertible (359 CI with aluminum head) uses Champion RJ8C spark plugs. It runs well with them.