jetfire prototypes - Gen I to IV

Jetfire I (2018) utilized two injectors to deliver air and fuel to the pre-chamber.  This was run as a single cylinder engine (SCE) with a sapphire topped piston to allow high-speed photography of the combustion process. 

Jetfire II (2019) utilized an electrohydraulic controlled poppet valve to inject air into the pre-camber. This SCE was fitted with a sapphire topped piston as with Prototype I.  Key learnings included timing of pre-chamber air injection.

Jetfire III (2020/21) was the first "metal" Jetfire SCE and used a "cartridge" containing the pre-chamber components.  A cam operated poppet valve introduced air in the pre-chamber.  This SCE was capable to operate with conventional spark ignition, passive pre-chamber, active pre-chamber, and with the patented Jetfire pre-chamber design.  Tests were performed over a wide range of conditions and operating points.

Jetfire IV, which is currently under testing as a SCE metal engine, adds independent pre-chamber volve timing utilizing TyssenKrupp's concentric cam, and two electric cam-phasers in a patented configuration.  Given the Omni-Fuel capabilities, testing is being performed with gasoline, heavy fuels, and gaseous fuels.  Indicated Thermal Efficiencies (ITE) of nearly 50% achieved thus far.