g741.org

Anyone have experience with this brand of spark plugs?
TIA

I found this online.
The Blue Crown Spark Plug company was based in Chicago during a time when the automotive aftermarket was in bloom. It was a subsidiary of Motor Master Products, which is believed to have distributed a range of more than 90 different spark plug brands during the 1930s and ’40s. The Blue Crown brand was marketed as a premium product, easily identified under the hood of a hot rod by the blue ring near the top of the porcelain on the plug.

World War II meant many companies relied on defense contracts, and during that time Blue Crown was producing 40,000 spark plus per day. Both before and after the war though, Blue Crown was known for the company’s racing efforts, sponsoring cars in races far and wide but most notably Offenhauser-powered single-seaters in the Indianapolis 500.

Purvis, (his father and Owner of the Blue Crown Spark Plug Co.) owned factories in Chicago and Mexico, with the Mexican plant being for international business, prior to selling Blue Crown to the Defiance Automotive Screw Machine Co. in Defiance, Ohio in the early 1950s.

Interesting, I have never heard of them. What made you ask about them? When I first saw your question I immediately thought it must be some offshore brand, but I couldn’t have been more wrong.
They have an interesting look to them. Too bad you wouldn’t see much with modern plug wires over them.

I purchased a set of 6 for the M37. Had fresh Autolite plugs in the engine, but wanted a spare set on the shelf. Never really looked at the brand until I saw a post on folks having issues with MECO plugs. Then thought "Oh crap" these might be MECOs. Looked closer then saw the branding. Will post pics later today. These are the water proof plugs, no internal blue ceramic like the one shown above.

Here are the pics of the Blue Crown water proof spark plugs.

Very Interesting find.

What is the part number that you purchased?

Bert

SR6F17 part number

Thank you for the part number.

Bert

thanks for the history lesson. now I want some