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Engine Block, Cast Iron, 4-Bolt Mains, 4.250 in. Diameter Bore, 1-Piece Rear Main Seal, Chevy, Big Block, Each
Part Number: NAL-19170538
Estimated Ship Date: Tomorrow
Estimated Ship Date: Tomorrow
Engine Block, Aluminum, 4-Bolt Mains, 4.250 in. Diameter Bore, 2-Piece Rear Main Seal, Chevy, Big Block, Each
Part Number: DRT-31264344
Not Yet Reviewed
Estimated Ship Date: Jan 29, 2026 if ordered today
Estimated Ship Date: Jan 29, 2026 if ordered today
Engine Block, Cast Iron, 4-Bolt Mains, 4.245 in. Diameter Bore, 2-Piece Rear Main Seal, Chevy, Big Block, Each
Part Number: WRL-095000
Estimated Ship Date: Jan 7, 2026 if ordered today
Estimated Ship Date: Jan 7, 2026 if ordered today
Need It Sooner? We recommend these similar substitute parts:
Bare Blocks, Dart Big M Series, Cast Iron, 9.80 in. Deck Height, 4.250 Bore, 4-Bolt Main, 2 Piece Rear Main Seal, Big Block, Chevy, Each
Part Number: DRT-31223344
Not Yet Reviewed
Estimated Ship Date: Jan 28, 2026 if ordered today
Estimated Ship Date: Jan 28, 2026 if ordered today
Engine Block, Cast Iron, 4-Bolt Mains, 4.250 in. Diameter Bore, 2-Piece Rear Main Seal, Chevy, Big Block, Each
Part Number: DRT-31264345
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Engine Bare Blocks, Dart Big M Series, Aluminum, 10.20 in. Tall Deck, 4.250 in. Bore. 4-Bolt Mains, 2 Piece Rear Main Seal, Chevy, Big Block, Each
Part Number: DRT-31264354
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Engine Block, Race Series, Aluminum, 4-Bolt Mains, 10.4 Deck, 4.250 in. Dia., Bore, 2-Piece Seal, Chevy, Each
Part Number: DRT-31264395
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Engine Block, Race Series, Aluminum, 4-Bolt Mains, 10.2 Deck, 4.250 in. Dia., Bore, 2-Piece Seal, Chevy, Each
Part Number: DRT-31264355
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Engine Block, Race Series, Aluminum, 4-Bolt Mains, 10.0 Deck, 4.250 in. Dia., Bore, 2-Piece Seal, Chevy, Each
Part Number: DRT-31264385
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Engine Block, Cast Iron, 4-Bolt Mains, 4.240 in. Diameter Bore, 2-Piece Rear Seal, Chevy, Big Block Mark IV
Part Number: NAL-19212196
Not Yet Reviewed
Estimated Ship Date: Mar 3, 2026 if ordered today
Estimated Ship Date: Mar 3, 2026 if ordered today
Bare Blocks, Dart Big M Series, Cast Iron, 9.800 in. Deck Height, 4.250 in. Bore, 4-Bolt Main, 2-Piece Rear Main Seal, Small Block, Chevy, Each
Part Number: DRT-31213344
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Bare Blocks, Dart Big M Series, Cast Iron, 9.800 in. Deck Height, 4.250 in. Bore, 4-Bolt Main, 2-Piece Rear Main Seal, Big Block, Chevy, Each
Part Number: DRT-31213345
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Bare Blocks, Dart Big M Series, Cast Iron, 10.200 in. Deck Height, 4.250 in. Bore, 4-Bolt Main, 2-Piece Rear Main Seal, Big Block, Chevy, Each
Part Number: DRT-31213354
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Bare Blocks, Dart Big M Series, Cast Iron, 10.200 in. Deck Height, 4.250 in. Bore, 4-Bolt Main, 2-Piece Rear Main Seal, Big Block, Chevy, Each
Part Number: DRT-31213355
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Bare Blocks, Dart Big M Series, Cast Iron,10.400 in. Deck Height, 4.250 in,Bore,4-Bolt Main,2-Piece Rear Main Seal, Big Block, Chevy, Each
Part Number: DRT-31213395
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Bare Blocks, Dart Big M Sportsman Series, Cast Iron, 9.800 in. Deck Height, 4.250 in,Bore,4-Bolt Main,2-Piece Rear Main Seal, Big Block, Chevy, Each
Part Number: DRT-31223345
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Bare Blocks, Dart Big M Sportsman Series, Cast Iron,10.200 in. Deck Height, 4.250 in,Bore,4-Bolt Main,2-Piece Rear Main Seal, Big Block, Chevy, Each
Part Number: DRT-31223354
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Bare Blocks, Dart Big M Sportsman Series, Cast Iron,10.200 in. Deck Height, 4.250 in,Bore,4-Bolt Main,2-Piece Rear Main Seal, Big Block, Chevy, Each
Part Number: DRT-31223355
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Bare Blocks, Dart Big M Series, Cast Iron,10.400 in. Deck Height, 4.250 in,Bore,4-Bolt Main,2-Piece Rear Main Seal, Big Block, Chevy, Each
Part Number: DRT-31223395
Not Yet Reviewed
Estimated Ship Date: Jan 5, 2026 if ordered today
Estimated Ship Date: Jan 5, 2026 if ordered today
Engine Block, Cast Iron, 4-Bolt Mains, 4.240 in. Diameter Bore, 2-Piece Rear Seal, Chevy, Big Block Mark IV
Part Number: NAL-19212197
Not Yet Reviewed
Estimated Ship Date: Apr 6, 2026 if ordered today
Estimated Ship Date: Apr 6, 2026 if ordered today
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