Rick,
The motor is bored .040" over. Wisco made the piston for the last rebuild, about 15,000 miles ago. I had a friend who owns a "old time" parts store that rebuild motors drop by and look at it yesterday. He said it look like carbon or some type of trash had got on top of the piston and cut the grooves. Maybe the motor was cranked and rev'ed up while it was cold. Anyway I'm going to pull the motor out of Mike's Cobra and get ready for a rebuild. This Cobra will not make it to the London Cobra Show this year but Mike is going with us. We always need Co-pilots.
Rick, what do you think about his cam specs? This is a street Cobra only, no racing but of course he needs respect at the red light
Dwight