Nope stock good engine can hit the 7.2k limiter which is about 144mph.
Speedos are a bit inaccurate but realy best gauge is hitting the limiter in top or GPS readout and adverages in both directions to account for hills etc.
Rubbish.
A Clio Mk2 Ph2 172, the shortest geared of all of them, is geared to 20.4 mph/1000 rpm in 5th. So the rev limiter, 7200 rpm, is at 146.8 mph. Every test of them said they'd do 138 mph standard. Getting to 146.8 would require 20.37% more power. That would be 207 bhp at the flywheel, 35 more than standard. The idea that all it takes is a "good" standard engine to get 207 bhp is nonsense.
The only way a standard Clio Sport is going to get to the rev limiter is if the rev limiter is coming in at 6700 rpm. Wait, hold on, they do when they're cold. Right?