Would there be a formula for figuring piston to valve clearance if you know your current clearance? My current clearance is .119" on intake and .170" on exhaust using clay. Would like to figure pv clearance on paper to see if I can fit the 278/288-.726/.726-108 cam without issue. this cam would be in at 104. If not I have a smaller default roller as well picked out. Both Harold Brookshire cams. If anyone has a known formula I would appreciate it if you could post it up. Thanks