Honestly, not worth the effort. If you want something with power and a stick, get a SSS.
You want a sedan with a stick and power, honestly, nothing modern. Subaru Impreza STi. But you wanna worry about maintenance cost, then again, get the SSS.
I'd recommend a BMW E36 or E46 with a 2.5L engine at least. 0-100km good for 7.6s
But more importantly that in-line six engine... they don't make engines like that anymore for normal BMWs.. now cars like the BMW 118i & 318i comes with an engine with 1 cylinder less than a Suprima, and less displacement.
Modifying your car is gonna be more pain than it's worth.