This engine probably looks and functions more like an axial piston injection pump than an old 2-stoke diesel.
Lightning Hybrids is not about to give away their secrets before the X-Prize race is over. (The contest has 10 million dollars worth of rewards. Should be interesting. It is open to anyone.) Yet they have given us a taste of what's to come so here is what I think they have.
Their 2012 concept vehicles (the LH4 and LH3) have a brand new power system called an "integrated hydraulic axial piston engine". What does that mean? Let's take it two words at a time.
The difference between the LH4 and Eaton's hydraulic launch assist system is where the compressed fluid transfers its power. Eaton's system relies on a transfer case like box and the fluid is delivered to the driveshaft. I am not sure but I think the LH4 has the fluid transfered into the driveline at the engine. So their engine has the choice to use either combustion or fluid or both to power the pistons. This might explain their "true cylinder deactivation". Hydraulics are also useful when it comes to energy storage and regeneration (the LH4 has 100 percent energy braking). A carbon fiber accumulator stores fluid up to 7,000 psi and then releases it for acceleration. Side note:Compressed springs would work too. They were used a lot at the beginning of the 20th century.
Axial Piston
This engine is similar to a Bosch axial piston injection pump.The best description I can think of for an axial engine is spinning pizza dough on your finger. Just imagine there being multiple fingers doing the spinning.
http://www.youtube.com/watch?v=MNqNPgE6CQ8
This engine burns diesel in two strokes (no valves). I doubt it will look like traditional two stroke diesels since axial engines don't have crankshafts either. I wonder if this engine's top end will look like FEV's OPOC 2-stroke diesel?
-Drag Coefficient .2 (on one of their videos I heard the windshield wipers are tucked in. They had to be since even one wiper exposed to wind would have created the same amount of drag as the entire car.)
Source:
http://www.lightninghybrids.com/index.html
Eaton.com
Hydraulic Launch Assist
Bosch
axial piston distributor pump