Yes, you really should get the head ported, they have restricted them for fuel economy and emissions, you could use the standard ecu and get it remapped but it is best to go for a full standalone job for something like that, and if you were feeling really adventurous you could take the bin the dizzy and coilpack and put a more modern wasted spark system in, which will get you a more reliable spark and you should be able to have bigger plug gaps, maybe you could use the coils off the gti6 engine (one per cylinder) and use the signal from the CPS, and for that you would definately need to go standalone, Motec are supposed to be the market leaders, however pug/citoren tuners tend to use ether emerald or dta due to the value for money aspect