For me:
135'ish - computed from the tach of a 1987 T-Bird Turbo Coupe
125 - 1995 V-6 Mustang
137 - 1997 Grand Prix GTP - Governed, would have run much faster
couldn't tell - speedo was pegged at 110 and was so tight it bounced - 77 Plymouth Fury Sport
170 knots/195 mph under NVG's - 93 Sikorsky Blackhawk - 2x1900 hp T701C turbines - many times
Sparky