Peripheral porting is the most Severe style of port you are able to do for the 13B-MSP, and it is generally reserved for racing needs. This kind of porting really should net you close to 50-60 hp. Usually exhaust constraints are traced to the catalyst and filters set up, so https://andersonukyqe.digiblogbox.com/54011619/the-best-side-of-mazda-13b-rew-motor-for-sale