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Here are a few pixs of the first powerhead (minus the head), almost ready for paint. Rob

looks fantastic!

Wow!

Great looking powerhead...did you bore each motor or just hone?

Hi Calvin,
The blocks were first degreased as best possible, then bead blasted with care. All machined surfaces were taped off to resist the blasting, I didn’t worry too much about the bores. I weighed both blocks just for shi*s and giggles to see how close they were.

I inspected them for any problems, and thoroughly deburred the blocks inside and out.
The blocks and bores were in good condition and I suppose they could have been done with a very light hone and new rings, but I tend to be a perfectionist.

I Hand picked four +.020 oversize pistons determined by condition, roundness and optimal size. I cherry-picked these from 15 pistons @ +.020.

On a vertical CNC machining center I set up the blocks in prep for boring, checking squareness to the crankcase mating surface, checking straightness of the bores, out-of round and the center to center distance of the bores compared to the crank CL to CL of the crank throws. I didnt rely on the spec's, but rather the true numbers off each crankshaft. I also confirmed the squareness of the bores and my set-up to the head mating surface.

I then bored them to within .002 of finished diameter using a bore gauge, keeping in mind the piston sizes I had handpicked and the factory spec on clearance.

Then using a Sunnen Engine Hone at work to take to finish size, and with the guidance of an "old timer", we put the optimal crosshatch and finish to the bores.
I then thoroughly scrubbed and cleaned the block and bores in several steps.

I oiled the bores properly then sealed in plastic and boxed them, then put in a clean & dry warm area until ready for use. (it took me about 3 years to get to that step)
Otherwise, I pulled them out for inspiration every once in a while, and to admire them.
(I know, Im nuts)

Rob