This complete set of four +0.040in oversize pistons is made for Austin Healey 100 BN1 and BN2 engines being rebuilt with the cylinders machined to suit this piston size. Supplied with piston rings, gudgeon pins and circlips, it provides the piston components required for all four cylinders.
This +0.040in set provides the appropriate piston size where cylinder condition or previous machining requires a larger oversize. The pistons, rings, gudgeon pins and circlips are supplied together for a complete four-cylinder rebuild.
The +0.040in size is measured relative to the standard piston diameter. The cylinder bores should be machined to suit the actual replacement pistons and the required piston-to-bore clearance.
Check the existing bore dimensions and required machining with the engine machinist before ordering. Do not select an oversize from the vehicle model alone. A separate high-compression piston range is available for 100M and Le Mans-type engine specifications.
A piston ring compressor is available separately to hold the piston rings in their grooves while the piston is installed into the cylinder bore.
