Grail Engine

Votes: 40
Views: 12095

Grail Engine Technologies corporation has developed a revolutionary two-stroke internal combustion engine (ICE) that achieves high fuel efficiency (100+ mpg) and uses multiple fuel sources (i.e. gasoline, diesel, hydrogen, natural gas propane - electronically controlled on-the-fly)

Two-stroke ICE designs have been in production for generations but are being discontinued due to emissions. Our unique proprietary design operates without cross contamination of oil and fuel within the combustion chamber or exhaust cycle – the first of its kind. With improved volumetric efficiency, utilizing the “Miller Cycle” and HCCI (Homogeneous charged compressed ignition) simultaneously, our engine will produce more power than conventional four-stroke ICE’s. These benefits are high fuel efficiency, compact recyclable operating footprint, lower harmful emissions than currently mandated - and no need for expensive environmentally damaging batteries.

Grail Engine Technologies will license their technology to other multi-market industries. Including, but not limited to: transportation, Marine, Agricultural, Recreational, Generators, Natural gas engines as well as DOD applications.

Our engine has less parts than the traditional 4-stroke ICE’s and is 50% cheaper to manufacture. The Grail Engine is the answer to our environmental need to reduce global pollution and minimize foreign oil dependence. This is an ideal adaptable multi-fuel drop-in solution that exhibits environmental benefits today and tomorrow without the complications of infrastructures needed to utilize other sustainable energy alternatives (i.e. electric batteries, hydrogen)
The Grail Engine Two-Stroke engine consists of:

- A single exhaust valve, 3 Pulstar Pulse Plugs and a Direct Fuel injector - all located at the top of the cylinder
- A single intake valve located within the piston
- A pre-compression chamber that houses a one-way reed valve
- 2 Vent-to-piston ports
- 2 Piston-intake-ports attached to the piston and travel within the vent-to-piston ports
- A crank case with minimized volume

The Grail Engine functions as follows:

Compression takes place within the reed valve air box, pre-compression chamber, vent-to-piston ports, piston-intake-ports & crankcase. As the piston travels upward creating a vacuum beneath the piston, fresh air enters via the intake air box through the one-way reed valve, and fills the external pre-compression chamber, vent-to-piston ports and piston-intake-ports with fresh air.

Compression occurs within the cylinder as the piston travels upward. At Top Dead Center (TDC), direct ignition then single or multiple ignitions occur. This forces the piston down into the cylinder compressing air in the engine crankcase, external pre-compression chamber, vent-to-piston ports and piston intake-ports. Just prior to Bottom Dead Center (BDC), the exhaust valve opens via a standard cam/push rod mechanism or electro-mechanical valve control. Exhaust gases exit via the exhaust valve opening at the top of the cylinder. Compressed fresh air enters the cylinder via piston valve, which forces out the final exhaust. As the piston travels past BDC the exhaust valve and piston valve close and cycle repeats.

Note: Our engine is capable of exhibiting, multi-fuel, on-the-fly "true" hybrid engine technology.

(For engine animation visit )


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  • Name:
    Matthew Riley
  • Type of entry:
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  • Matthew's favorite design and analysis tools:
    Autodesk Inventor, Autodesk Showcase, Autodesk Algor Simulation, CONVERGE™ CFD Software using high performance Xi Computer workstations (
  • For managing CAD data Matthew's company uses:
    Autodesk Vault
  • Matthew's hobbies and activities:
    Developing Internal Combustion Engine technology
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  • Matthew is inspired by:
    I strive for excellence and perfection in design to make a positive choice for humanity.
  • Hardware used for this entry:
    Xi Computers (, MAC Tools, Stanley Vidmar,
    Software used for this entry:
    Autodesk Inventor, Autodesk Showcase, Autodesk Vault, Autodesk Algor,
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