This Centerforce billet steel flywheel is a problem-solver for certain LS engine swaps using a transmission from earlier (non LS) applications. Certain '99-'00 Chevy 6.0L truck engines and possibly certain early 4.8L LS engines have a "long" crank offset that is 0.400" different than the rest of the LS engine family. These early LS engines have a crank offset that matches earlier (non-LS) Chevy engines even though they are within the LS engine family. When mating these engines to an earlier non-LS transmission, such as a Muncie 4-speed, this flywheel is required to ensure the starter ring gear is in the correct position to work with the block-mounted LS starter. Centerforce(R) steel flywheels are manufactured from high quality billet steel and match closely to the original equipment flywheel weight. Billet steel flywheels are available for popular import and domestic vehicles, including trucks. Centerforce steel flywheels are CAD/CAM-designed and CNC-machined from billet steel for precise, no-hassle, bolt-in installation. Centerforce billet steel flywheels are SFI-certified, so you know that you can count on them, on the street and on the track.