Hi, thank you for the tip, but I'm afraid it's a standard piston with 6,2:1 CR, beeing a Hepolite 11210.
What I need is either a Hepolite 4469 (7,5:1 with three compression rings, no oil ring),
10431 (7,5:1 with two compression rings and one oil ring)
or 11548 (8:1 with two compression rings and one oil ring).
Ariel W/NG '43 (RAF) "Bitzer", Triumph Thruxton '04, IZH-49 '56, Tempo Standard 150 '54.