OK. To bore you even more, here are a few photos. Note the valve-to-valve clearances. Elaboration to follow. MikeV
Four heads with different cams and valves.
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One of the NCR heads (a set) found laying in the grass at Barber Motorsports at 2011 Ducfest event. Still a work in progress; they were rough. Plans are for NCR cams and 42.5/37mm valves. See my custom valve gap measuring tool.
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One of the J Precision converted heads with 42/35mm valves and Montjuich cams, now fully assembled. Note the measuring tool.
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Same head, with an example of how I use the tool for crude measuring.
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One Pantah head with 41/35mm valves installed by Carlo, now assembled with 900SS cams. A similar set with a bit more porting and high-compression pistons ran really well in a true 600 (583cc) engine - until I managed to blow it up!
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A near-stock Pantah head with a 39mm intake valve, minimal porting, and Montjuich cam. Performance was underwhelming. A perfect example of how just changing one or two things will get you nothing. But they are not harmed, and still have a future.
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