I feel you, my previous car was a Volvo V70 2.4 20v, now I have a Doblo T-Jet. I made all the plans: intake, turbo, piping, intercooler, exhaust, cams, injectors... to make it a 250hp sleeper van. But in the end, it's still a heavy van and all that money and effort wouldn't make it faster than the average 10yo hothatch.
The low gearing combined with just intake+tune make it quick enough to surprise most people and to have to negotiate for grip launching and cornering despite 235 wide tyres.
I'm keeping the money I save for other things and maybe one day I'll get me an Abarth Evo or a quick Giullietta for having fun.