This Type 528 engine, serial number 40858, was originally produced for a 1954 "Pre-A" Porsche 356 1500 Super. It underwent a multi-year rebuild completed in early 2026, featuring a two-piece magnesium case, cast-iron cylinders, revised pistons, a 356B-spec crankshaft, oversized main bearings, Bosch distributor, 6-volt generator, and twin Solex 40 PBIC carburetors. The engine has been run on a test stand but not installed in a car since completion.