The 360 engine is Mopar's most effecient engine. The bore and stroke of this engine is such that it achieves optimum efficiency. Many people report 20+mpg out of their hi performance 360 engines with standard carburetion. This engine was designed with a cast crankshaft and larger heads than the 318. Although it is possible to find good 360 heads and put them on a 318 which will yeild mild performance gains. Sometimes the 360 heads will need to be milled down to keep the compression due to the larger combustion chamber. More specs soon!