The 340 engine was not designed for use as a truck engine.
However, It was designed to be a competitive small block,
easily succeeding those in its class. Note that in
later years (1972-1973), the 340 was seriously de-tuned before it was phased out in 1974 (1970-1971) due to emission regulations.
This engine Utilizes an extremely large bore to stroke ratio,
similar to the ford 289 or the chevy 327. Due to its short
piston stroke, this engine can reach very high RPMS. However
the large bore of the 340 makes for large pistons which tend
to cause a bit more reciprocating weight inside the engine.
This may be the engines single down fall, aside from its rarity.
The particular engine above has been built to achieve somewhere
near 450HP. More specifications coming soon!