Closed chambers gone bad… that’s a wrap

haven’t measure each piston yet, these speed pro supposedly install .020 above top deck. Not sure if the PO had the deck milled, I’m assuming they did cuz he told me bottom end was redone and used .030 over pistons. That’s the only thing he didn’t have paperwork for.

These heads are the SM 65cc closed chamber ones 2.02/1.6 valves, running hughes 1.6 rockers bringing cam to .512 lift. 7.775 pushrod length, thing was hammering but not a bottom end noise thought maybe it was rockers/valve adjustment. Then I used the camera scopes the spark plug holes and saw the piston hitting when spinning over by hand, ever so close.

To me on the one pic (cyc2) it looks like the valve relief area actually hit the bottom of head, not worried about valves they are okay, but I think it damaged that piston.

Not sure where to go with this yet, def thought about running slight thicker gasket- I was making 170-180psi in all holes so compression was spot on.

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