Trying to get my new flathead cranked and doesnt seem to wanna hit. I have Autolite 216 and Edelbrock heads. Seems like the thread depth in the head is much longer than the length of the plug. Would this make any difference? What plug is recommended?
Aluminum heads have weaker threads than iron heads. So people who make alunimum heads usually make them thicker over the valves so that they can have more threads, use a longer plug, and have the head last a long time before lauching a plug at some bystander. So, yes you need longer plugs. Use all the threads.
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