The 383 stroker engine is typically installed in a vehicle to increase horsepower and torque. The GM small block 5.7-liter 350 is the base for the 383 stroker; the 350 crankshaft is exchanged for a GM small block 400 crankshaft. The 400 crankshaft rod journals produce a longer stroke for the engine and create a larger displacement. Professional machining of the engine is required.
The 383 stroker engine has a bore of 4.03 inches and a stroke of 3.75 inches versus the GM 350’s bore of 4.00 inches and 3.48 inches of stroke. The 383 cubic inches are calculated by the following formula: the bore of 4.030 is multiplied by the bore of 4.030 then multiplied by the stroke of 3.75 then multiplied by 0.7854, then multiplied by the eight cylinders to equal 382.668. This total is then rounded up to the displacement figure of 383 inches.