Stock Bigport Engine + ITB?s?!

[Uzelac]

I'd say ITB's look and sound very cool but on stock internals they are pretty useless performance wise.
They will cost big money, you will have to change ECU, buy/make adapter and airbox and after all of that, you will see little or no performance advantage.

If you are planning further upgrades (cams, pistons, exhaust header) ITB's will get along very well with them. But i'd say they are far from mandatory, and really beside looks and sound, you don't gain much performance with them.

I've been through all this, speaking from personal experience.