Hupmobile Model 20 Spark Plugs

What spark plug is used in the Model 20 Hupmobile?

Phil

I have AC 78L Commercial . Not sure if that number is current.

Ken

Thanks. I've also heard Champion W89D, PJ85, and 3COM. What was the original plug used?

Phil

[My entry listing Hupmobile Model 20 Spark plugs got lost in the Forum's recent hacking incident, so here is a re-post]

I'll attempt to answer my own question, courtesy of a spark plug collector I've corresponded with. The Hupp Model 20 used a standard-length 7/8" - 13 TPI plug, one of the more common types. The Model A Ford used this size plug, I believe. The original plugs used by Hupmobile were probably Champions. The Champion #JAS43 is a period type that would be correct. The Autolite #T9, Blue Crown (Tak-a-part) #2, Bowers C78H will fit. Also, Edison #35 and Firestone #S80C are correct. Most every spark plug maker had this size available, including Rajah and Splitdorf (the latter having the pretty green hexangonal body).

Phil

G,day to all.

I have not come across a Hup 20 with 7/8 spark plugs. the ones in Australia were shipped with 18MM. So long as they are not mica put modern plugs above the exhaust valves to burn off the soot. Happy Hupping Max BURKE Nulkaba 2325 Australia