Porting 596 Heads
Seats can help or hurt you on the exhaust.
If they cut too deep or the cutter removes a ledge above the cut, or how it wipes out a lot of that little ledge on the outside short turn ... None the less the ex short side has it's taller side, inside ssr, that comes off the wall, and with grinding can be exploited to deliver substantial flow increases.
From the seat... light radius, almost minute, then straight up and just smooth the top where it turns into floor. On the tall side that angles upward and becomes the wall....port straight up off the seat on that side of the bowl and then widen the ssr width by grinding into that wall, same idea as the intake near the head bolt. You'e creating more ssr. Open the far side bowl almost to the seat, grind the guide flat to the roof, don't gasket match exit, grind roof kink some, beware of water....then just polish it all.