340 stroker 422

Miszny said

Heads are from 67 to 67.5cc.
They are bolted on, did some work today. Tomorrow will cut pushrods, put carb on it and wait till there is time to start this thing.
I have ngk bcp7es plugs, should I give them a shot or go to 8 from the start?

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What is your final compression ratio? If that plug is an extended tip there is no way I’d start with that. You need a standard reach plug. Start with that in an 8 heat range and tune from there.


One of the things with high CR pump gas engines is extended tip plugs. Sometimes you just can’t use them.

Which is why I said plug selection is critical.