I dont dare to go fast in M1 motorway anymore, i remember i was cruising pretty fast , suddenly saw a brick in middle of road
now this car i was driving was just 4inches off the ground so i had to steer around the objects on road prety quick to avoid a hole in engine sump in case i hit something hard.
good luck with yr SC installation, let us know how did you manage the fuel management for F/I and how durable was that