The king of all big block crate engines is the ZZ 502/502, with torque and horsepower that will have you grinning and streetable manners that have your competition wondering what hit them. The ZZ 502/502 represents our latest and best efforts to develop awe inspiring big block power in a dependable, durable and driveable big block crate engine. Details: The king of all big block crate engines is the ZZ 502/502, with torque and horsepower that will have you grinning and streetable manners that have your competition wondering what hit them. The ZZ 502/502 represents our latest and best efforts to develop awe inspiring big block power in a dependable, durable and driveable big block crate engine. With its big valve aluminum heads, roller camshaft and complete dyno tuned induction and ignition system, this is as close as you will come to a custom built 502 at crate engine prices. And for those that like to grind on heads, change cams, mill for compression or whatever, we've left it only partially assembled. Make no mistake, everything you need is there, but you don't need to disassemble anything to make head mods or an intake swap. It really is the best of both worlds, bolt it together and go, or tweak it to meet your specific needs. It's like someone at GM Performance Parts has been there, and we have. The ZZ 502/502 makes extensive use of aluminum to keep weight down. Including aluminum heads, intake, water pump, and valve covers. Additionally, this king of the crate engines is full of heavy duty parts, to ensure that it will be making awesome power for a long, long time. With its forged aluminum pistons, forged shot peened steel connecting rods with 7/16" bolts, forged steel crankshaft, four bolt main block, stainless steel valves, 6 quart oil pan, and windage tray, the ZZ 502/502 seems more like a custom race engine than a crate engine. With a 5800 rpm redline it might just feel more like a custom race engine than a crate engine too. Available as a long block kit or a complete engine kit, the ZZ 502/502 is designed to meet your needs. The base kit includes a fully assembled short block with 2.25" intake aluminum heads, valvetrain, aluminum valve covers, torsional damper and 14" automatic transmission flexplate. The complete engine kit adds an aluminum intake manifold, 850 cfm carb, complete ignition system, gear reduction starter and aluminum water pump. Both kits include hardware and gaskets for all parts included in the particular kit. Finally "some assembly required" is a good thing. The ZZ 502/502 is not intended for marine use, and should only be used in 1976 and earlier pre- emissions street vehicles or any year off road vehicles.