Merlin IV Block, Billet Splayed Caps 9.8" Deck 4.495" Bore 1

WOR 095010

Merlin IV Bare Block

Deck Height 9.800"
Bore 4.495"

Material:  High density cast iron
Deck thickness:  .600" minimum 
Maximum recommended bore:  4.620"
 Crank clearance:  4.375" stroke crank without clearance
Deck height:  9.800" (standard Chevrolet) or 10.200" (tall)
Main caps:  Splayed steel billet main caps

Prop65 Warning Icon

WARNING: Cancer and Reproductive Harm –

Marine Crate Engines

The Merlin IV Block is a perfect choice for high performance marine applications.  It incorporates important features of the Pro Race block such as reinforced bulkheads and main webs, thicker decks, and a priority main oiling system plus essentials for marine use such as utilizing the stock Chevy oil pan pattern, OEM 2.750" mains and 100% compatibility with Mark IV Bow Tie components.  The nodular iron 4-bolt mains provide the necessary support for high RPM operation while maintaining excellent bearing wear. Indexed lifter bores assure optimum reliability.  World Products blocks are manufactured to QS-9000 specifications.



  • Material: High Density Cast Iron
  • Deck Height: Standard 9.800"
  • Deck Thickness: .600" minimum
  • Cam Bearings: Standard Chevrolet
  • Main Bearings: Standard Chevrolet
  • Camshaft Location: Stock
  • Lifter Bores: Indexed (stock .8437" bore)
  • Bore: 4.240 (hone to 4.250") or 4.495 (hone to 4.500")
  • Maximum Bore: 4.625"
  • Cylinder Wall Thickness: .250" at 4.620" bore
  • Water Jackets: Expanded for better cooling
  • Lubrication: Priority main oiling system
  • Filtration: Integral mount for spin-on filter
  • Oil Pan Rails: Solid (stock width)
  • Crank Clearance: 4.375" stroke
  • Main Caps: 4-bolts splayed, nodular iron or billet steel
  • Fuel Pump: OEM mount
  • Starter: OEM mount
  • Motor Mounts: Dual (front and side)
  • Cylinder Head Holes: Blind tapped to prevent leaks
  • Weight: Approximately 270 lbs.


Compatible with all Mark IV components

All Merlin IV Blocks need finish machine work to complete.

Remember: TCM offers complete machine service and block preparation

More Information
Model WOR 095010
SKU WOR 095010
Write Your Own Review
You're reviewing:Merlin IV Block, Billet Splayed Caps 9.8" Deck 4.495" Bore 1
Your Rating
To Top