I believe I've found another parts swap that might benefit people who are building up a 261 engine. Pistons that fit a Nissan forklift are very similar to ones for a 261 engine, and they're designed to be used with flanged, slip-fit sleeves so the block never has to be rebored again. The same piston/sleeve assemblies can also be used in modified 248 and 270 GMC engines with a longer stroke crankshaft. Yes, the wrist pins are way too big, but that's fixed easily by putting bronze bushings in the piston pin bosses.

www.ebay.com/itm/195096233829?

www.ebay.com/itm/403393893525

I can get 3/8" extra stroke from either the Chevy or GMC crankshafts by sleeving the connecting rod bores down to a smaller diameter, offset grinding the crankshaft, and using a connecting rod bearing for an Allis-Chalmers tractor. That brings the Nissan pistons almost to the top of the block.
Jerry

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