Well it was Teddy, Courtney or Jim. Sorry their phone service was short with you. They usually are full of information on the phone.
M47 Crank is excellent that's what I run and the stroke makes a big difference in torque. The motor is more powerful out of boost and in boost it's just plain nasty. The crank is bullet-proof
If they gring on the head just make sure they are very light with the grinder. Only take material from the inside radius of the valve pocket. There is not much area to improve. I think like 6% in flow which is not a bunch of HP but adds up with other mods. When you boost porting does not make a big difference since you are forcing air past restrictions. On a N/A car porting is needed when all other mods are in place.
I hope this clears things up. It can help but done wrong it will hurt you bad and ruin the head. This is a fact
