Cast Iron SBC Pro Lightweight

Cast Iron SBC Pro lightweight Engine Block 

World's new Motown Pro Lightweight block offers tremendous performance potential in a new lightweight package that will appeal to both circle track racers and drag racers.

Weighing in at a nominal 178 lbs, the Motown Pro Lightweight is cast from a special 40,000 psi iron alloy for increased strength while weighing significantly less than typical aftermarket blocks. The new block is available with either a standard SBC cam journal and lifters or with a BBC cam journal and .904" lifter bores to provide enhanced valve train stability and performance.

Ductile iron main caps are fitted with 4 bolt splayed caps on #2, 3 & 4 and 2 bolt caps for #1 & 5 which allow easy oil pan fitment. The main caps are secured by high strength 7/16" ARP bolts for maximum stability.

TECHNICAL SPECS:

  • Material: 40,000psi High Density Iron
  • Deck Height: 9.025" (standard Chevrolet)
  • Deck Thickness: approximately .600" minimum
  • Cam Bearings: 2.000" or BBC 2.120" cam bore
  • Camshaft Location: Stock
  • Lifter Bores: Indexed. Standard .842" or .904" bore diameter.
  • Main Bearings: Standard Chevrolet (350 style)
  • Bore Spacing: Stock 4.400"
  • Bore: 3.995" or 4.120"
  • Maximum Bore: 4.200" Cylinder Bores 
  • Steam Holes: Block cylinder bores are of a Siamese design. Because of increased cylinder wall thickness, it is not necessary to incorporate steam holes for street use.
  • Cylinder Wall Thickness: Approx. .250" @ 4.200" bore
  • Water Jackets: Expanded for better cooling
  • Lubrication: Priority main oiling system
  • Oil System Features: Integral boss for front feed, boss for rear scavenge rear main cap has provisions for wet sump pump, drilled for dry sump valley scavenge lines
  • Dip Stick: Driver Side
  • Filtration: Integral mount for spin-on filter
  • Oil Pan Rails: Solid (stock width) can be clearanced for strokers
  • Crank Clearance: 4.000" stroke (H-beam steel rods)
  • Main Caps: 4 Bolt Nodular steel Splayed
  • Main Cap Locators: Stock registers and ring dowels at the center studs
  • Main Cap Hardware: ARP 7/16"
  • Rear Main Seal: 2 piece design
  • Fuel Pump: Standard OEM 
  • Starter: Standard OEM
  • Oil filter mount: Standard OEM
  • Motor Mounts: Standard OEM
  • Cylinder Head Bolt Holes: Blind tapped to prevent leaks
  • Weight: Approximately 178 lbs.
  • Cam Bearings: Durabond DT1T 2.000" 
  • Block Dowel/Plug Kit: BMP 703890B-1K
  • Oil Restrictors: Std 1/8"NPT plugs (drill to required size)
  • Rear Seal: FEL2909