There are many unknowns regarding the new GM (Chevrolet) “spec engine” that has been approved for competition at a handful of tracks, most notably Motor Mile Speedway.  What is known is that it is fast and it is already a hit among Late Model Stock Car racers.


The new “spec engine”, officially called the Weekly Track “SPEC” Engine, isn’t exactly a spec motor in the literal sense.  It’s more of an upgrade to existing built engines.  The new package includes aluminum heads and a roller camshaft.  The motor is intended to make more speed and create more parity in Late Model Stock Car racing while also reducing costs to the racers.


300x250 51 Network 2017(2)“I think the words ‘spec engine ‘name might be misleading,” South Boston Speedway competitor Mark Wertz, who has tested the new motor package, said.  “I think it’s a name they came up with because it has more of a spec head and intake.  It’s just an upgrade.  However, Dodge introduced a Dodge crate spec engine in 2004.  The problem was, it put out too much power at the time.


“Ford’s spec engine was what the crate motor was originally introduced as but continues to be upgraded,” Wertz continued.  “Ford has introduced a spec motor but they continue to tweak it which led to too much horsepower.  Chevrolet now, the builders are trying to introduce an upgrade that they’re calling a spec motor that can compete with Ford.”


Wertz, who has won multiple championships at the now-defunct Langley Speedway, has been a driving force behind the new engine along with former NASCAR Whelen All-American Series director Lynn Carroll and automotive tech guru Shayne Laws.  He feels the new package will ultimately cut down costs for teams who run built engines.


“It can allow some of the teams who struggled with handling issues, steel head motors, to catch up a little bit,” Wertz explained.  “And, I think it will allow some of the teams that have had to spend a lot of money to get a set of steel heads worked up to where they make good horsepower numbers.  Before, teams couldn’t find the set of heads they need to make good horsepower numbers.  Now, they’ll be on more of an even playing field.”


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-Original story by Andy Marquis for

New GM Spec Engine Creates Rift in Late Model Stock Scene