The 25 is the way to go no need for plenum just run fmic,piggy back ecu greedy ulitimate or link , larger injectors i used 550cc high flows, z32 airflow meter coil packs i used yellow jackets a garrett 3076 or a hypergear highflow 14psi actuator, intank pull pump i use a walbro, surge tank and external 044 this combo on a s1 made 244kw on 15 psi through an auto so for a manual you woulf expect 260ish then chuck some pon cams in turn up the boost you should see 280ish maybe more (still have my injectors for sale) lol