Jirre, we all do really know someone like this... I've had the misfortune of stumbling across several of these characters.
Like the chap in matric, Jacques... Rustenburg of all places..
His pa has a Ford Sierra XR6 - the proper 1-2-3 car (1 liter brandy, 2 liter coke, 3 liter Ford)... 'n Moerse freeflow and a holley carb slapped onto the thing. Big beat, fokol speed - it made okay torque, but like all the Essex-based 3-litres, they weren't particularly made to rev, and the power dropped off early.
Tall tales of it not being very quick on the pullaway, but hitting 280 km/h while racing a superbike, while the 5th gear ratio would go nowhere near that... Also kakstories of how we could "feel the power up to 4500 RPM" but how he wasn't allowed to rev it higher than that because the new race motor was still busy being run in.
About 2 years or so later, it just so happened that the same little red Sierra had a run-in at a traffic light with a slightly fettled black Superboss that just so happened to belong to yours truly.. Suffice to say the Supey kakked all over him so bad, that he declined a top-end run and quietly skulked off home.. Shamepies, he must've still been running the motor in.
That was where I learnt not to argue with someone who talks that much kak - just nod and smile, then make them look like a proper doos later on.