Thanks for a nice unambiguous answer to this question, it's good to know. Is 9:1 too high to run smoothly on Shell V-Power unleaded?
The pistons are Hepolite. They are still in their original box, which says they are part number 11412. This number is also cast into the inside of the piston skirt, and there is another number on the other side: 3568 AM 413.
Rowan