Modular Head Shop - 0940 Series - Gas Nitrided Top, Cast Iron 2nd 1.2mm x 1.5mm x 3mm

0940 Prefix -The 0940 prefix is a NPR Ring Set consisting of a Gas Nitrdided Steel Top Ring, RBT Cast Iron 2nd Ring and 3 Piece SS Oil Ring Set. The Gas Nitrided Steel Top Ring works very well with power adder applications and can withstand very high cylinder pressures. Very similar to the AP Steel, but not the same. This Piston Ring Set is included with the 4.6L / 5.4L Competition Series Pistons. This Piston Ring set uses a 1.2mm x 1.5mm x 3mm Ring Stack. These Piston Rings are a direct replacement for all Ford Modular PN's with a R1 suffix from 3.552" - 3.572" Bore and are not interchangable with any of the earlier part numbers.