Technical Flathead Spark Plugs

Anybody tell me what the hottest Flathead spark plug is available?

 

Champion H-11 was considered a hot plug in it's day. May I ask why you would need a hotter plug?

 

And I saw there is a Champion H12, apparently.

 

I'm an NGK man myself

 

H-10(stock) is a fairly hot plug itself. If you have to step up to h-11 or h-12 either your jetting is wrong or you are burning(using) oil and hotter plugs may or may not make your situation better. If you are using air filters that hinder airflow,they are prone to making your engine too rich or fat,hence the reason for hotter plugs.

 

Like the H-10 in a flattie because that's what I run in my Studie.....

 

I've run H-10's and Autolite 216's in my basically stock 8ba. Not much of a difference between the two, IMO. Running 216's right now.

 

I run h 10 in my 51 merc flatty

 

CHAMPION H10 used on lincoln zephyrs

 

Also on single cylinder Briggs and Staten lawn mower engines.