this time. Chrysler built millions of these engines with so many racing variations that the history alone could easily fill a book. Quick references and focusing on availability kept it within the covers. So hats off to Indy Heads (cast iron and aluminum), Edelbrock (aluminum), and B1 (aluminum) for maintaining key performance parts for the small-block.
The small-block program had many ups and downs, many parts programs that came and went, and too many racers who helped with these competitive efforts to name individually, but thanks to all! I owe a lot to the many contractors and Chrysler engineers: Ted Flack, Al Nichols, Tom Hoover, Pat Baer, Bill Hancock, Tim Zuehlke, and Jim Szilagyi, with special thanks to John Wehrly. They taught me well! I also want to thank the many manufacturers that display their new hardware at events and shows such as PRI & SEMA; their representatives are always willing to answer questions and discuss the latest hardware.
I thank Rob Cunningham of Mancini Racing and Bob McSwain and Rob Miela of Godfather Racing for their help. Plus a big “thanks” to Gary Stanton, Ron Keselowski, and Larry Henry for helping me with history data conflicts.
The writing and photography required for an engine book is a lot of work but not anywhere near the amount of work that went into the design and development of the parts originally. Extra thanks to Scott Koffel, Dave Koffel, Leonard Lawson, and Greg Charney for helping with the photographs and their leading-edge creations, along with Frank Parker for the real heavy work.
I owe the most thanks of all to machinist Richard Koffel, and engine builder Dan Parker, and the 340 engine’s owner, Charlie Henry. I couldn’t have done it without them! They all put in lots of time to help me put photos and words together.
Perhaps most of all, I must thank my editor, Paul Johnson, for his patience, guidance, and foresight. He took a tremendous number of words and photos on small-blocks and made it fit into this book and be readable.
I would like to give extra special thanks to my wife, Linda, for her steady hand in keeping our household going during this project and accepting the huge piles of research material and photographs that I used to create this manuscript.
Any discussion of the Chrysler/Mopar small-block V-8 engine has to start with the introduction of its ancestor, the A-engine, in 1956, but the original engine was relatively bulky and heavy. By 1962–1963 it was obvious that the compacts needed more power, so the LA-engine was created. The A-Body was the compact-size cars produced by Chrysler called Valiants and Lancers.
Equally important in the engine’s design was having less weight; after all, it was going to be installed into smaller, lighter vehicles.
A Bit of History
The new engine went into production in 1964 as the 273 LA-engine. Its name, “LA,” comes from one of its three major design parameters, lightweight A. The new engine was designed and developed under the engineering code of A828.
1965
In 1965, the 273 engine was upgraded to 235 hp with the addition of a 4-barrel carb, high-performance cam, higher compression ratio (10.5:1), and black-painted valvecovers. This high-performance package was developed under the A861 engineering code. Next was the 318 with a bigger bore (3.91). The new 318 also had hydraulic tappets and cam and stamped steel rocker arms, and it was rated at 230 hp.
The old-style 318 or the original A-engine, also called the poly-sphere engine, shares the same displacement number (318) with the new LA-engine, but the old engine’s valvecover is held on by only two screws: one on each end.
The new V-8 engine was originally referred to as the A-engine. The A-engine was the older version introduced in 1956. Over the 30 years of production, this distinction has been lost and all 1964 and newer small-blocks are now referred to as A-engines.
1968
In 1968, the performance version of the A-engine was introduced as the 340. The 340 engineering code is A105 and it features a big bore (4.04 inches), bigger valves (2.02/1.60 inches), high-flow, bigger-port cylinder heads, heavy-duty forged steel rods, beefed-up block and mains, bigger hydraulic cam, high-rise intake manifold with larger runners, high-flow exhaust manifolds, viscous fan, and windage tray. The result of all this hardware was a 275-hp rating with 340 ft-lbs of torque.
1970
The 340 6-barrel engine (called the A340) was added in 1970 in the Trans-Am cars (called Challenger T/A and AAR Cuda), which were intended for SCCA Trans-Am road racing. The 340 6-barrel engine package featured three 2-barrel Holley carbs, an aluminum high-rise intake manifold, modified cylinder heads, adjustable valve gear, and heavy-duty 340 block bulkheads for potential four-bolt mains. The engine was rated at 290 hp and 345 ft-lbs of torque. The 340 6-barrel was only produced in 1970.
1971
The final production A-engine displacement increase was introduced in 1971 as the 360 engine. The 1971 360 was built only as a 2-barrel carburetor, which continued for the first three years of production. It was introduced just prior to the new federal emissions laws of 1972, which required the use of low-octane fuel, which required lower compression ratios. The engine was originally built in Chrysler’s Windsor, Canada, engine plant.
The 1964–1967 273 LA-engine looked small, but it is actually the same size as the 340 and 360. The bigger engines got bigger air cleaners and high-rise intake manifolds that make them look bigger.
The 340 was Chrysler’s standard high-performance engine for many years. The basic parts of the 340 package were very good performance parts.
One of the higher-output crate engines, and certainly one of the largest small-blocks, was the 408-ci version with aluminum heads.
A unique crate engine was the Magnum MPI version (360 or 5.9L) with the high-flow intake manifold.
The new 360 engine featured a longer stroke (3.58 inches) at the stock deck height (no raised block), 4.00-inch bore, smaller intake valve (1.88 inches), external-balance weights at each end of the crankshaft, and cast crank with larger main bearing diameters (2.81 inches). It also included block core holes similar to the 340 lined up on the halfway point between the adjacent bores, which allows steel shot to have better aim and access to the water-jacket in the cleaning process to clean out core-sand. In addition, the main bolt spacing was increased by .31 inch. With an 8.7:1 compression ratio, the result was a 255-hp rating.
1974
From a performance standpoint, 1974 was a milestone date because the 360 replaced the 340 as the small-block
