1275 +60 HIGH COMPRESSION PISTON - SINGLE

Low drag 1275 piston standard size 2.780 plus 60 thou oversize (Rings included). This piston has a possible compression ratio of 10.3:1 as fitted to Cooper RSP 1990. The engine then becomes 1328cc The best performance 1275 pistons are C-STN100 range which have 9.73cr when the piston is 1mm down the block. Current pistons differ from the 60s originals and now have a "low drag" slipper skirt design and a shorter lighter 20.6mm wrist pin. Wrist pin height is 1.5276" to crown with a top dish of 8cc. Performance is enhanced by the use of 3mm oil rings and the smaller drain slot behind this ring decreases the risk of breakage and 2 of 1.5 mm compression rings. Crown depth to first ring is about 10mm Rings are R41570-60. AE Hepolite is now owned by Federal Mogul and trademarked "Nural" .Now Nural stamped 87-524114-00 Sold singly,4 per engine required--