Hartley Enterprises specialies on custom high performance engine kits for sport and recreational use.  2.8 and 3.0 liter V8 engines have been built in the past.  The present focus is on 4 cylinder NA and turbo engine kits and development projects.



The BOLT 4 is a 16 valve L4 engine.  It utilizes the Suzuki Hayabusa head and incorporates race car  features such as a high capacity alternator, flywheel with an automotive race clutch, adapter for Hewland and other gearboxes, robust crankshaft, advanced dry sump oiling system and low crankshaft center height .  See BOLT 4 Specs. page for details. 
A current project is a 1.4 liter BOLT turbo using a Borg Warner EFR turbo and water/air intercooler.  It will mate to a Hewland JFR gearbox as shown.





Left is an intercooler designed for this project.  It uses a compact water cooled core.  It can handle 28 psi boost, 500hp applications while cooling the intake air to 138 deg. F.

The intercooler fits the intake on a Suzuki Hayabusa head an may be offered as a stand alone product in the near future.






  Hartley Enterprises working on the following projects:

  • 2.8 and 3.0 liter BOLTV8  The design is completed and released to manufacturing. Protype engine to be track tested late 2015
  • 900cc 3 cylinder high efficiency engine The target market is power generation for plug-in automobiles.  Design goal is 80 hp continuous and 50% thermal efficiency using improved adiabatic combustion and unique combustion pressure control.