This is a subject that isn't talked about a lot. I'm just finishing my cylinder heads and would like to see what others are doing in this area. I started with stock factory heads, pocket ported the intakes and polished the exhaust ports. I purchased Ferrea valves that are larger than the originals. Stocks were 2.08in/1.74ex new valves are 2.19in/1.90ex. I'm sending them off next week for new silicon bronze guides, new seats, and a three angle cut. If anyone has done this in the past, what gains did you get? I'm going to take pictures before I send them off and will post later.