2161.982848.6410
Dart Big "M" Cast Iron Engine BlocksMade In The USA
Dart Big 'M' Cast Iron Engine Blocks   With multiple deck heights and bore sizes up to 4.600', the Big M Sportsman block gives you the versatility to build a wide variety of engine combinations. A true priority main oiling system oils the main bearings before the lifters for extra reliability. BB Chevy Big 'M' ...
DartBig M Cast Iron Engine Blocks

Dart

Dart Big "M" Cast Iron Engine Blocks

Made In The USA

From: $2,161.98
Select Engine Block
Please Select
31263354
Competion Bore: 4.25 in. Deck: 10.2 in.
$2,848.64
31263344
Competion Bore: 4.25 in. Deck: 9.8 in.
$2,530.00
31263454
Competion Bore: 4.5 in. Deck: 10.2 in.
$2,589.80
31263444
Competion Bore: 4.5 in. Deck: 9.8 in.
$2,589.80
31263654
Competion Bore: 4.6 in. Deck: 10.2 in.
$2,589.80
31263644
Competion Bore: 4.6 in. Deck: 9.8 in.
$2,589.80
Sportsman Bore: 4.5 in. Deck: 10.2 in.
$2,161.98
31273444
Sportsman Bore: 4.5 in. Deck: 9.8 in.
$2,161.98
31273654
Sportsman Bore: 4.6 in. Deck: 10.2 in.
$2,161.98
Sportsman Bore: 4.6 in. Deck: 9.8 in.
$2,161.98

Applies To Continental U.S. orders only

FREE Ground Shipping
Specifications
Block Specifications
Main Journal Type
Standard BBC
Engine Block Style
Stock/OEM standard deck
Deck Height (in)
See Options
Cylinder Bore as Shipped
-.010 over
Cylinder Bore Diameter
See Options
Engine Block Material
Cast iron
Engine Block Weight (lbs)
280 lbs.
Main Bolt Style
See Options
Main Caps Included
Yes
Main Cap Material
Ductile iron
Main Cap Fasteners Included
Yes
Main Bearings Included
No
Rear Main Seal Style
2-piece
Finished Cylinder Bores
No
Raised Cam Location
No
Cam Bearings Included
No
Freeze Plugs Included
No
Quantity
Sold individually.
Notes
Block bores are .10 undersized to allow for piston set up.
Description

Dart Big "M" Cast Iron Engine Blocks

 

With multiple deck heights and bore sizes up to 4.600", the Big M Sportsman block gives you the versatility to build a wide variety of engine combinations. A true priority main oiling system oils the main bearings before the lifters for extra reliability.


BB Chevy Big "M" Sportsman Series - Ductile Caps
Part Numbers: Bore Size: Mains: Deck Height:
31273444 4.500" Standard 9.800"
31273644 4.600" Standard 9.800"
31273654 4.600" Standard 10.200"
Sportsman Series Blocks Features:

  • Standard 9.800" and tall 10.200" deck heights available for stroker engines.
  • Standard 4.250" , 4.500" or 4.600" bore sizes with siamesed extra thick cylinder walls to resist cracking and improve ring seal (minimum .300" thick with 4.625" bore).
  • Uses +.300" tall Gen VI style lifters. Modification for Gen IV style available.
  • Scalloped outer water jacket walls improve coolant flow around the cylinder barrels to equalize temperatures.
  • 4 bolt ductile iron main caps have splayed outer bolts for extra strength.
  • True priority main oil system lubricates the main bearings before the lifters. Darts stepped main oil gallery (9/16" to 1/2" to 7/16") increases the flow of oil to the crank at high rpm, and Darts front oil crossover eliminates internal oil leaks around the distributor shaft.
  • Oil filter pad is drilled and tapped for an external oil pump.
  • Lifter valley head stud bosses prevent blown head gaskets.
  • Rear main cap uses standard oil pump and two piece seal - no adapter required!
  • Mechanical fuel pump boss, clutch linkage mounts, and side and front motor mounts simplify installation in any chassis.
  • Dual oil pan bolt patterns fit standard and notched oil pans.
  • Small bore 396 version available
  • Coated cam bearings, freeze plugs and dowels are NOT included.


BB Chevy Big "M" Competition Series - Billet Steel Caps
Part Numbers Bore Size Mains Deck Height
31263344 4.250" Standard 9.800"
31263354 4.250" Standard 10.200"
31263444 4.500" Standard 9.800"
31263454 4.500" Standard 10.200"
31263644 4.600" Standard 9.800"
31263654 4.600" Standard 10.200"

Competition Series Blocks Features:

  • Standard 9.800" and tall 10.200" deck heights available for stroker engines.
  • Standard 4.250" , 4.500" or 4.600" bore sizes with siamesed extra thick cylinder walls to resist cracking and improve ring seal (minimum .300" thick with 4.625" bore).
  • Uses +.300" tall Gen VI style lifters. Modification for Gen IV style available.
  • Scalloped outer water jacket walls improve coolant flow around the cylinder barrels to equalize temperatures.
  • 4 bolt billet steel main caps have splayed outer bolts for extra strength.
  • True priority main oil system lubricates the main bearings before the lifters. Our stepped main oil gallery (9/16" to 1/2" to 7/16") increases the flow of oil to the crank at high rpm, and our front oil crossover eliminates internal oil leaks around the distributor shaft.
  • Oil filter pad is drilled and tapped for an external oil pump.
  • Lifter valley head stud bosses prevent blown head gaskets.
  • Rear main cap uses standard oil pump and two piece seal - no adapter required!
  • Mechanical fuel pump boss, clutch linkage mounts, and side and front motor mounts simplify installation in any chassis.
  • Dual oil pan bolt patterns fit standard and notched oil pans.
  • Coated cam bearings, freeze plugs and dowels are included.
  • Dart engineered the Big "M" to be the strongest, most reliable & easiest to build
  • Has true "priorty main" system that oils all of the main bearings before the lifters
  • Sportsman blocks have nodular iron main caps, center 3 are 4 bolt & ends are 2 bolt
  • Sportsman blocks do not come with cam bearings, freeze plugs & dowels
  • Competition blocks have all billet steel 4 bolt main caps
  • Competition blocks include coated cam bearings, freeze plugs & dowels
Application List
ImageSKU / Part NoApplicationStockPriceAdd to Cart
DAT31263354 DAT31263354Select Engine Block: Competion Bore: 4.25 in. Deck: 10.2 in.0$2,848.64BUY
+ -
DAT31263344 DAT31263344Select Engine Block: Competion Bore: 4.25 in. Deck: 9.8 in.0$2,530.00BUY
+ -
DAT31263454 DAT31263454Select Engine Block: Competion Bore: 4.5 in. Deck: 10.2 in.5$2,589.80BUY
+ -
DAT31263444 DAT31263444Select Engine Block: Competion Bore: 4.5 in. Deck: 9.8 in.2$2,589.80BUY
+ -
DAT31263654 DAT31263654Select Engine Block: Competion Bore: 4.6 in. Deck: 10.2 in.0$2,589.80BUY
+ -
DAT31263644 DAT31263644Select Engine Block: Competion Bore: 4.6 in. Deck: 9.8 in.1$2,589.80BUY
+ -
 DAT31273454Select Engine Block: Sportsman Bore: 4.5 in. Deck: 10.2 in.2$2,161.98BUY
+ -
DAT31273444 DAT31273444Select Engine Block: Sportsman Bore: 4.5 in. Deck: 9.8 in.1$2,161.98BUY
+ -
DAT31273654 DAT31273654Select Engine Block: Sportsman Bore: 4.6 in. Deck: 10.2 in.2$2,161.98BUY
+ -
 DAT31273644Select Engine Block: Sportsman Bore: 4.6 in. Deck: 9.8 in.2$2,161.98BUY
+ -
Customer Reviews
Share your thoughts with other customers
Login to leave a review
Questions & Answers
Be first to ask a question

TEASoftware