Our author was correct when he said initially the ZR-1's LT5 motor made 375hp.
https://corvettestory.com/Corvette-zr-1-2.phpZR-1 motor statistics:
Designation: LT5
Configuration: V8, 350 cu. in., four overhead camshafts, four valves per cylinder
Intake: Multi-port fuel injection
Compression Ratio: 11.0:1
Horsepower: 375 @ 5800 RPM (1990 to 1992)
405 hp @ 5800 RPM (1993 to 1995)
Torque: 370 lb-ft @ 4800 RPM (1990 to 1992)
385 lb-ft @ 5200 RPM (1993 to 1995)
Bore/Stroke: 3.90" (99 mm.) x 3.66" (93 mm.)
Block: Aluminum; Nickasil coated cylinder liners
Heads: Aluminum, cross flow