Piston Metro Turbo Mega 9.4cr + .040 Only 9.38cc Dish Each

Sold as a single piston and although for Turbos is from original Rover casting and tooling to run on 5psi turbo boost. If using more boost you need to be working on a lower CR with a total cylinder volume of 55cc in piston/block/head gasket and cylinder head. Also when increasing Boost pressures it is essential to have a modified ignition advance/retard curve to prevent detonation and ensure the Inlet charge temperature does not exceed 40 degrees C by the fittment of a suitable Intercooler. If our advice is not followed it is very likley you will break the ring lands on your new pistons.