Not trying to hijack this post, Just wanted to show
@Chainlube something
I wish resurfacing my Whizzer heads was that easy There's alot of surface to sand on a Whizzer head
As you can see I shave em down to increase the compression
That extra S/P hole is for a compression release button. That was used on the Ambassador, It has a starter
For my NE 5 I just plug one of the holes with a bolt, NE5 has a compression release lever on the valve cover
Or for that extra hole I could get a duel coil and use 2 S/P
That Ambassador head is nicknamed the Block Head because it's thick and has short cooling fins
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