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I've got an odd potential problem with a block after machine work was done. I'd like to ask if any of you have any issues with a bore campher like this?
I took this to a reputable race shop. I had them bore and hone the block and set up my ring end gaps. They radiused the top of the bore, which made assembly quite easy (the pistons literally fell in). But, after placing my head gasket it looks like the beveled edge could slightly undercut (maybe .010 - .015") a portion of the head gasket (depending on where the gasket can shift upon the alignment dowels). Before I load up the block and have the shop re-inspect, are there any thoughts any potential problems here?... or am I just over thinking this?
I had thought about using a larger bore cometic head gasket. However, these are thicker (0.40") than the oem (0.30") gasket. I already have too much quench area with the JE 9:1 pistons (they are .020 below deck).
I remember an old trick that an engine builder showed me once. It used to be that you had to O-ring your block with a steel wire as the oem gaskets were often not able to hold with high compression or forced induction. What he showed me to do was to paint the gasket with a light coat of shaker can silver spray pain (which is essentially aluminum suspended in the paint) to help glue the gasket exactly where you wanted it; and keep it from slipping when installing the heads. I think that I'll do this.
I wonder if the other low compression pistons (wiesco, supertech, etc) deck out at -.020? Even the OEM msm pistons deck at -.005 (0.035" piston to head clearance) and have attention to the blending of the quench area to the minor dome. You'd think that a purpose built performance piston would be designed at least as thoughtfully as OEM.
OEM MSM miata pistons @ TDC JE 9:1 @ TDC