Motor City Flathead cyl heads

I am just ***embling an engine which I'll be fitting with these heads. The sparkplug thread depth is much longer than the stock heads [which run Champion H10 plugs]. A Champion N9Y-c is the correct length for these heads, but has a protruding elctrode and I don't know about the heatrange. Any Hambers have a sparkplug heatrange equivalence chart for differing lengths? Or, anyone been there- done that and can advise a starting point? Thanks, I'm Tooratly

 

N9 The Y means extended electrode.

 

There have been several heads from MCF.Not sure if a designs are all the same.Post a pic of top and bottom and I will get you the right info.

 

Send an email to info@shadowrods.com with "Attn: Mark Kirby" in the subject line. Or start at http://www.shadowrods.com . Motor City Flathead id affiliated with Shadow Rods these days.