How to Identify 340 Mopar Heads

Save

The 340 c.i.d. Mopar engine, popular with engine enthusiasts during the 1960s and 1970s, was introduced in 1967 and produced until 1973, when emission regulations ended production. According to Allpar, the 340 is known for its cylinder heads, which were high-flow with large intake and exhaust valves. Casting number identification is essential because these heads are particular to the 340 itself and becoming a rare find. In 1971, the 340 was issued with "J" heads, which were cast the same as the 360 c.i.d., but with different valve machining.

Things You'll Need

  • List of Mopar cylinder head casting numbers
  • Remove the valve covers to access the cylinder head casting number. According to the website My Mopar, the casting number is located either on the valve intake runner or on an intake runner on the the underside of the cylinder head. The number is seven digits long.

  • Remove the cylinder head to locate the casting number if it is not located on the top of the head and the head is still on the engine. Removing the cylinder head requires replacing the head gasket and properly fastening the bolts according to torque specifications during re-assembly.

  • Decode the casting number. Casting numbers must be referenced against a casting number chart, such as the ones found on the websites Motortopia and My Mopar. There is no user-friendly way to decode Mopar cylinder head casting numbers.

Tips & Warnings

  • When removing valve covers, be sure to replace the valve cover gaskets during re-assembly.
  • Removing and re-assembling the cylinder head is not recommended to those without experience or an above-average mechanical aptitude.

References

Promoted By Zergnet

Comments

You May Also Like

  • Ford 302 Cylinder Head Identification

    Identifying Ford 302 cylinder heads is a matter of locating and decoding the casting number stamped directly on the head. The 302...

  • The Timing Specs on a Dodge 360

    The Dodge 360 engine was first introduced in 1971 by Chrysler Motors. The 360 engine was featured on various trucks, such as...

  • What Is the Mopar 340 Wedge Engine?

    The Wedge engine was a Mopar motor that utilized a particular type of combustion chamber. However, many Mopar enthusiasts are confused by...

  • How to Identify Mopar Heads

    Identifying Mopar cylinder heads can go from being a simple task to a difficult one, depending on where the casting numbers are...

  • How Do I Identify Cylinder Head Castings on World Heads?

    Since 1987, World Products has manufactured a full line of aftermarket cylinder heads for high-performance Ford and Chevrolet engines. There are essentially...

  • The Best Mopar Heads

    The Chrysler Corporation, or Mopar, manufactured many vehicles known for high performance and elevated horsepower during the 1960s and 70s, with breakthroughs...

  • Mopar 318 Engine Identification

    The Chrysler-produced Mopar 318-cubic-inch V-8 engine originated as an "A" series engine in 1955, and was produced through 1966. In 1967, the...

  • Mopar 340 Engine Specs

    The Mopar 340-cubic-inch engine was manufactured for the model years 1968 through 1973. This engine was the performance small-block option in the...

Related Searches

Check It Out

How To Travel For Free With Reward Points

M
Is DIY in your DNA? Become part of our maker community.
Submit Your Work!