I don't disagree with anything Stamford and Factory Fast have said (except about ECUs - If you are looking for serious power and control you have to look beyond the likes of megasquirt IMO). I just think that today's boy racers have it easy compared to when I was one
We spent hours playing around with distributor weights and springs (only way to alter timing advance curve back then) instead of re-maps, offset cam dowels rather than vernier pulleys, twin carb balancing nightmares instead of programmable fuel injection.
There were no 'tuning houses' for the humble BR, we only had Burtons, All Car Equipe and a pre-Halfords Ripspeed. A lot of trial and error was involved. Today, you can go to a tuning company and spec an engine producing 437bhp and the bits will be picked off the shelf to supply that power.
Back in the late 70's I bought one of the first nitrous systems imported into the country. Very basic, either on or off. Now, we have variable control, programmable, multistage systems.
170bhp at the wheels was almost unheard of back then. Now, most shopping trolleys have more! If you wanted to increase power a lot of mods were required. Now, it is simply a matter of punching a few keys.
Personally, I think we had more fun, but I would. But then again, a 500bhp+ Elan should be more interesting than the previous 168