Here in this episode (#9) of PowerTec 10, DV explains what needs to be done for a basic but very effective porting job on a 2 or 2.3 Liter Mazda four cylinder engine. This is a great way to bolt on 50 hp to a normally aspirated build or 70-100 hp for the same boost on a turbo motor. Get advice from the guy whose turbo modded heads have simply crushed the hi-buck pro teams at big events.
