Spark plug piston clearance issue

#1
Howdy all, Just checking to see if this is common or not.
I am building a gx200 clone.
Had .065 taken off the head, chamber measures 15cc. However, it was obvious when I was cc'ing the head, the stock Chinese spark plug was protruding quite a bit below the deck of the head, about .045. I figured this was going to be an issue, as I only have .035 piston to head clearance. The piston is a flat top.

The Chinese spark plug is a projected tip, I believe a non-projected tip spark plug will work fine.

I know most run the 3910x, put it looks to be slightly projected into the chamber. Haven't measured one in my head yet though..
I haven't really seen much talk about spark plug to piston clearance issues, so was a little surprised to run into it.

I know I add washers and raise the plug..but was wondering what others have done.

Rick
 
#2
Common, I just milled a new head .047 and when I went to cc it the plastic plate was held up by the ground strap of the plug. I had to take it off to cc the head. It was originally a 22cc head. When assembling a milled head I used indexing washers to get it to the deck of the head or slightly above it.
 
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