Milodon's Crankshaft Scrapers can give additional "free" horsepower by removing any excess oil left on the crank and rods that the windage tray does not remove. These Crankshaft Scrapers require fitting to individual crank and rod profile, as well as to engine stroke. Crankshaft Scrapers should be fitted to within .045" from rods and .035" from crank counterweights. When installed, the scraper is sandwiched between pan rail and block. For Chevy small and big block engines.