366T 396 402 427 427T 454 502 ALL Chevy big blocks used...Mains-2.7488"-2.7495"---Rods-2.20"
CHEVY 348-409 "W" MOTOR V-8 Crankshaft Journal Sizes
348 409 427 "Z-11" ALL "W" family motors used...Mains-2.50"-Rods-2.20"
All journal sizes are given in "STANDARD" sizes. Your crankshaft may have been cut down in size previously by a machine shop. Make sure your crank will work in the block you have. Blocks were made for each crank main journal size. If you are putting a "small" or "medium" journal smallblock crank into a "medium" or "large" journal smallblock block you will need crank bearing "spacers" or use special "thick" bearings available from aftermarket suppliers.