Doesn't matter. As long ans the bore is correct, jetting good, maintence done, and quality oil you will be fine. Done a few cast piston motors. Never any piston related issues.
order the OMI clamp. I'll find it on ebay and post a link for you. Not a expensive part and totally worth it.http://www.omiproducts.com/2010Pages/StemMounts.htm
Do normal leak down see if pressure drops. If it does open rad cap check for bubbles.
But coolant should be pretty noticeable on spark plugs too if it is.
Don't run it to much anymore. A hydro lock is no fun.
Oh. So cam didn't say wich pipes will work best? Isn't that something that was discussed? I don't know for sure but the porting could possibly be different for each pipe.
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