DARTON SLEEVES MID SLEEVES HONDA CIVIC TYPE R FK2 FK8 FL5 K-SERIES K20CMany production cast iron and aluminum blocks suffer from a design weakness of cylinder stability by nature of poor support at the upper deck area. The manufacturing process of cast in sleeves provides for economy of scale in low horsepower engines, but does not accommodate high horsepower, high boost, or larger bore sizes. Darton has engineered a superior patented (patent #6,799,541) solution by using a unique designed cylinder sleeve which when