Performance Crate Engines

Prior to the availability of aftermarket blocks, performance enthusiasts were faced with the dilemma of scouring junkyards looking for 4-bolt main blocks or trying to fit 2-bolt blocks with aftermarket cap kits. Now you have a choice between standard 4-bolt main blocks with nodular iron caps and splayed billet caps. Rest assured that the 4-bolt setup will provide excellent reliability for most applications. For the serious performance enthusiast, the splayed billet setup is preferred for several key reasons. The illustration below shows a cross-section of a block casting, and the relationship between bolt holes and themeat" of the block. As you can see, the splayed bolts have a much betteranchor" due to available material thickness. The multi-directional clamping of the splayed bolts also helps improve bottom-end durability.

TECHNICAL SPECS

• Material: High Density Cast Iron

• Deck Height: 10.200"

• Deck Thickness: .600" minimum

• Cam Bearings: Standard Chevrolet

• Main Bearings: Standard Chevrolet

• Camshaft Location: Stock

• Lifter Bores: Indexed (stock .8437" bore)

• 4.240 (hone to 4.250") or 4.490 (hone to 4.500")

• Maximum Bore: 4.625"

• Cylinder Wall Thickness: .250" at 4.600" 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: 4.750" stroke crank

• Main Caps: 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