Getting ready to start a port/polish effort on a C9 head from a 250. My goal is a mild street/strip job. I will be focusing on cleaning up casting flash, smoothing the short-side turn, working the valve guide bosses, cleaning the exhaust ports, and potentially port matching the exhaust. This is going onto the 200 that is currently in my mustang. I intend to cc each chamber after cleaning them up and try to match them as close as possible before having the head surface milled. I am shooting for a static compression ratio in the neighborhood of 9.5:1. Not at work so I don't have my homebrew program in front of me to let me know if that is achievable without flat tops and/or a zero-deck. This is just where I would like to head. I already only use 93 so this shouldn't affect me at the pump. Thinking chamber volume of 50-52 cc will suffice for what i want but I will double check when i reach that point.
The bottom end is stock as far as I know. My questions are
1. Is it wise to port match the exhaust to the gasket? I've read that this is good but have also read that it is best to leave the cylinder head port slightly smaller to prevent too much reversion.
2. I've seen plenty of examples of how to shape the intake valve guide boss that I'm confident i understand the proper form, however, I'm not as confident on the exhaust side. Should i maintain the teardrop form here as on thin intake or is this not as crucial on the exhaust side (ie. I can just smooth this guy with the top of the port?
3. Is it worthwhile to pop the freeze plugs and work the runner? I plan on direct mounting a 2V so i think I can access 1,3,4, and 6 but not overly confident i can do much for 2 and 5.
I haven't built a flow bench nor do i really have the time and space to do so. This means my goal isn't airflow optimization, but rather just to free the breathing up a bit for the old girl. I've been through the Falcon performance HB section on porting a few time and also been through Vizard's book. I more reading is no substitute for doing, but I'm sure I can achieve my modest goals.
Am I missing anything big here at all?
The bottom end is stock as far as I know. My questions are
1. Is it wise to port match the exhaust to the gasket? I've read that this is good but have also read that it is best to leave the cylinder head port slightly smaller to prevent too much reversion.
2. I've seen plenty of examples of how to shape the intake valve guide boss that I'm confident i understand the proper form, however, I'm not as confident on the exhaust side. Should i maintain the teardrop form here as on thin intake or is this not as crucial on the exhaust side (ie. I can just smooth this guy with the top of the port?
3. Is it worthwhile to pop the freeze plugs and work the runner? I plan on direct mounting a 2V so i think I can access 1,3,4, and 6 but not overly confident i can do much for 2 and 5.
I haven't built a flow bench nor do i really have the time and space to do so. This means my goal isn't airflow optimization, but rather just to free the breathing up a bit for the old girl. I've been through the Falcon performance HB section on porting a few time and also been through Vizard's book. I more reading is no substitute for doing, but I'm sure I can achieve my modest goals.
Am I missing anything big here at all?