CHEVY V-8 Crankshaft Journal Sizes


Here's a list of Chevy V-8 crankshaft journal sizes. 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.

CHEVY SMALLBLOCK V-8 Crankshaft Journal Sizes

Gen.I, "Small Journal"
265...Mains-2.30"-Rods-2.00"
283...Mains-2.30"-Rods-2.00"
302...Mains-2.30"-Rods-2.00"
327...Mains-2.30"-Rods-2.00"

Gen.I, "Medium Journal", includes "Vortec" 305 and 350 thru '98
262...Mains-2.45"-Rods-2.10"
267...Mains-2.45"-Rods-2.10"
302...Mains-2.45"-Rods-2.10"
305...Mains-2.45"-Rods-2.10"
307...Mains-2.45"-Rods-2.10"
327...Mains-2.45"-Rods-2.10"
350...Mains-2.45"-Rods-2.10"

Gen.I, "Large Journal"
400...Mains-2.65"-rods-2.10"

Non-production Gen.I combination, using Gen.I 400 crank in Gen.I 350 block
383...400 crank, Mains cut to 2.45"-Rods-2.10"

Non-production Gen.I combination, using Gen.I 350 crank in Gen.I 400 block
377..."Spacer" or "thick" main bearings with 350 crank-Rods-2.10"

Gen.II, "Medium Journal", includes "L-99" 265, "LT-1" 350, "LT-4" 350
265...Mains-2.45"-rods-2.10"
305...Mains-2.45"-Rods-2.10"
350...Mains-2.45"-Rods-2.10"

Non-production Gen.II combination, using Gen.II 265 "L-99" crank in Gen.II 350 block
302...Mains-2.45"-Rods-2.10"

Gen.III, includes '97-2005 "LS-1" Corvette, Firebird, Camaro
345...Mains-2.558"-Rods-2.10"

Corvette "ZR-1", DOHC, "LT-5"
350...Mains-2.76"-Rods-2.10"


CHEVY BIG BLOCK V-8 Crankshaft Journal Sizes

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"