One way of looking at the Baca engine is this, the Baca engine is a true Eight Stroke by design, but it is a four stroke by function. It uses two non-compression strokes to maintain two charges of air into a high energy chamber prior to loading the charge into the piston cylinder with a fuel-air mixture. One thing to keep in mind is this phrase, "two strokes in, two strokes out." This high energy chambers function is to recycle the heat and shock wave energy, normally lost or wased, back to the fuel air mixture. Once this fuel and air mixture is raised to a higher energy level, it is transfered to the piston cylinder to be ignited by the spark plug, the combustion of the highly energized gases drives the piston down to produce power or work.
Prior to the compression stroke when the piston is at the bottom of its travel, there is an equalilizing pressure, both in the hi energy chamber and the piston cylinder. Under normal operating condition there are about four piston cylinder volumes per cylinder in the high energy chamber. This design does not allow the piston to totally extract the full volume of fuel air mixture out of the high energy chamber. The fuel air mix left in the chamber is left to absorbe more of the heat and shock wave energy thus making the energy transfer to the remaining volume of fuel and air mixture more effective.
By using two charges of cylinder air for a normal operating stroke gives the Baca engine a capacitor charge effect, it has two normal operating sizes; the actual size, and the operating stroke size. The operating stroke size is twice the actual size. For example; if the actual size is 0.5 liter, then the operating stroke size is 1.0 liter.
When an automotive manufacturer designs a car, they must incorporate the largest size engine needed for that paticuliar vehicle. The four stroke engine lacks the ability to store reserve power, even though under normal operating conditions the engine is only utillizing a small percentage of its potential. The Baca engine has two design functions of storing reserve power. One is by artificially asperating the hi-energy chamber with air stored in a compressed air tank, the other is the hi-rev potential of the engine. A small engine, like a motorcycle engine, can run at very hi revolutions per minute, some engines can run as high as 15,000 rpm's.
The Baca engine's first prototypes, the Alpha prototypes, will be small motorcycle engines reconfigured to an eight stroke design. The engines will be about 500cc's or about 0.5 liter in size. These engines will incorporate a ceramic metalic composite head design. The ceramic design will be for heat containment, refering to the hi-energy chamber.
About 30 years ago there was a new design for a ceramic engine. This ceramic design allowed the engine to run at very high operating tempertures. There was one major problem with the engine, even ceramic engines need lubrication. The optimum temperture for fuel eff. and power,for this engine, was about 550 degrees and at this hi temperture all of the lubricants would simply evaporate. The expensive ceramic engine would simply destroy itself from heat and friction. The Baca engine gets around this heat problem by only raising the energy level of the fuel air mixture, the engine normally runs at the same operating temperture as that of a four stroke engine.
