The GM Performance Parts aluminum race blocks offer you the same competition-level strength of our cast iron race blocks, with the added benefit of reduced weight. This allows your chassis builder to put together a more balanced racecar while not sacrificing any strength under the hood. The GM Performance Parts aluminum race blocks come CNC-machined, made from their super-tough aluminum, and ready to battle. If you want to go around corners at 200 mph or make over 1000 horsepower with a fuel-injected, turbocharged combination, this is your starting point.