VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 Spark plug adapters

Has any one else got a set of 14mm to 7/8" spark plug adapters, I bought a set for my 28 ute years ago from a guy at a Sydney swap meet, should have bought 4!! and now looking for a set for my speedster but can't find anyone making them,

Also my work sop manual has gone walk about points gap should be 18 thou right? Ray

You can get the Champion W89D long reach plugs that work really well and have the correct threads for the 4 cylinder heads.

I use Autolite 3077 or Champion W89D long reach plugs, with the gap set at .035".

And, yes, the point gap is set for .018 thousandths.

Cheers, Dean

I'm in Australian Dean, 7/8' plugs only come from US and the price is not cheap, I have had the 14mm in my ute for 20 years just makes it so much easier to get a range of plugs, this is for my second car a 28 speedster so I'm thinking the 14mm will give me better options on the heat range etc, as its higher compression and twin SU carbs. Ray

Hi Ray,

That all makes sense.

Can you get some old unusable plugs with the 7/8 thread, destroy the ceramic, and tap the metal that is left to receive a 14mm plug? Basically make your own adapters.

Just pulling ideas from the air.

Dean

Yeah Dad suggested that, we have a bunch of old Champion 5 plugs, but the first problem is there isn't enough meat to cut a 14mm thread, also the hex would have to be cut off so you can get the plug far enough down in the head to be effective, I might set up to make them my self as they would fit a multitude of cars Ford , Chrysler and GM of that era all used 7/8' the only non-metric size plug by the way, my 25 Indian uses 18mm plugs ! Ray

Snyder's has them for Model A. Combined with a 25mm long plug, they work well in the Chevy head.