I passed my driving test in 1982 having just turned 18 and had already bought my first car - a MG Midget 1275 (this was when car insurance was a little more affordable!) I'd had a Saturday job in Sainsburys since I was 16, a paper round for years before that and had saved up enough to buy that little car before I could legally drive. The engine was removed, pistons enlarged and block rebored to 1340 if I remember correctly, I fitted a lightened flywheel, special clutch, ported the head and added LCB Janspeed manifold and straight through one box exhaust system. Twin carbs were enlarged from 1 ¼ to 1 ½ inch and K & N Filters added. That little car flew - and I don't remember uprating the brakes!
I've been improving every car I've owned ever since, ensuring they stop better as a priority first but the performance and other subtle additions have always been a part of enjoying car ownership. I'm turning 50 this year (can't quite believe it!) and I'll never stop modifying my cars, however subtlely. Saving for a REVO remap now!