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What is the next step in engine design?

I heard someone mention that the push rod 2-valve design is 60 years old. Before that there was flathead engines, correct?

So if they changed up the design on motors, what is the next step? (and yes the engine does have to run on gas or something of the like, not battery power)

Fortunately, most engines today are overhead cam three and four valve designs.

Flatheads were once the pinnacle. L heads preceded those. That’s a design where the ports were on one side of the chamber.

In truth while the basic suck-bang-blow by reciprocating pistons has basically changed little in concept, the design of engines has evolved considerably. Fuel metering, combustion chamber design, ignition systems, reciprocating parts designs, and countless other details are far more eveolved than they used to be. And the devil is in the details.

The next step in the reciprocating engine part of the motive force (everything will go to hybrids, but that wasn’t your question) may be more evolution in valve control. Right now valve timing is being introduced to all engines. Perhaps valve duration will also become variable and controlled. Perhaps both will be controlled by a computer.

I’m just guessing, of course.

I read somewhere a couple of years ago that GM engineers were working on an engine that didn’t need to be cranked to start. Apparently, a air/gas mixture would be injected into one or more cylinders that were in the right position, the air/gas mixture would be ignited forcing the piston down and the engine would be running. I don’t remember all the details, but if this could be worked out, it would eliminate the starter motor and a high amperage battery thus lightening the vehicle.

I also remember reading an article in Popular Science written by Smokey Yunick about an engine made out of ceramic. A ceramic engine could be run at higher temperatures and promote better efficiency. Smokey Yunick is long gone and I don’t know what became of his idea.

BTW, the old flathead engines had two valves per cylinder, but the valves were in the block. These valves were opened directly by the camshaft just as they are presently on an overhead camshaft engine. Having the engines in the block, however, did not allow for a good combustion chamber design and the engines weren’t as efficient as having the valves in the cylinder head. Even some simple one cylinder push type rotary lawnmowers are equipped with overhead valves.

Speaking of the efficiency of valve in head engines as opposed to flathead engines, in a test of the 1959 Studebaker 259 cubic inch V-8 against the 1959 Studebaker 169 cubic inch flathead 6, the V-8 Studebaker Lark and the 6 cylinder Studebaker Lark got almost identical gasoline mileage.

Carbon Fiber Engine components are already in use in a limited production.

Personally I don’t think the current engine will last much past another 30-40 years.

I’m not a big import guy but doesn’t honda have a variable valve timing, v-tec? I’m not too sure how advanced this system is but I’m sure it could be improved. I believe toyota has a variable intake plenum that increases power. For the most part the recpricating engine is fairly maxed out as far as design is concerned. They’re probably about as efficient as they’re going to get. I think emissions is the main concern nowdays.

Has anyone heard of the five stroke engine? it works by injecting water into the hot cylender and “blowing up” into steam.

The big problem with ICE is waste heat. Smokey Yunick modified a Plymouth Horizon to get 70-100 miles per gallon. He did it by recycling as much heat as possible back into the engine. Engineers will think of ways to convert all the wasted BTU’s into usable power. When you buy gasoline or diesel fuel, you are paying for BTU’s. 70% of them escape out the exhaust, radiator and brakes…

I read somewhere a couple of years ago that GM engineers were working on an engine that didn’t need to be cranked to start. Apparently, a air/gas mixture would be injected into one or more cylinders that were in the right position, the air/gas mixture would be ignited forcing the piston down and the engine would be running. I don’t remember all the details, but if this could be worked out, it would eliminate the starter motor and a high amperage battery thus lightening the vehicle.

Sounds very similar to the 80 or so year old Coffman Cartridge starter systems used in airplanes. Batteries were weak back then and so extremely heavy and bulky. Cartridge starters produce a loud bang and I imagine that any system relying on a gas/fuel mix from a dead stop would also be explosive and loud. One advantage of electric motor cranks is they spin up the engine rather than starting from a dead stop. Would be interesting to see their concepts…

I’ve not heard of a five stroke engine. Since it takes two strokes for a piston to return to its starting position, it would seem that any variation would need to be an even number to have a repetative action ongoing. Strokes would need to be 2, 4, 6, or whatever.

But I’m listening. If you could explain how such a thing would work it would be an interestng conversation.

I have heard of water injection where water is injected into the inflowing airstream to cool the air and increase its density. Is this the idea you’re thinking of?

We could go back to flat heads. You never know what’s next.

http://www.faqs.org/patents/app/20080202454

kind of what I was talkng about.

Maybe valves operated electrically, like fuel injectors are… that would eliminate the friction and moving mass of camshaft, valve stems, rocker arms, etc.

I don’t know if the friction and mass take up much energy compared to what it takes to accelerate the car and keep it moving through. Maybe more of the benefit would be from the wider range of control of valve timing and opening and closing rates that a computer would be able to accomplish.

Post us what you can find as being the highest current level of production vehicle IC engine design (include induction) and we will go from there. Must set a base to see where your comming from,you do mention flathesds.

I don’t log on links that people don’t say where they are taking me,why be so mysterious?

Sorry - valves are mechanically operated. VVT differs from VT in that many different points on the intake valve lift camshaft can be computer selected depending on rpm, load, demand to operate fuel injectors. VT is on or off one condition of rpm, load and demand. Direct fuel injection spark operated is now available selected Ford and GM engines. The system reduces pumping loss efficiency due to the throttle plate. Diesels don’t have a throttle plate. The Homogenous Charge Combustion Ignition gasoline engine operates similar to a diesel engine with combustion via compression heat. However, the engine can operate this condition under certain conditions. When conditions are not met, ignition is by spark. Next step is gasoline ICE solenoid operated valves. In test for several years but no design suitable for mass produced gasoline engines to date.

5 stroke engine

Unlike concepts from unproven start up companies, this is designed by the builder of F1 engines.

There is also a six stroke design. Where the strokes are as follows: intake fuel and air, compress it, power stroke, exhaust, inject water on top of hot piston for another power stroke, exhaust, repeat.

Were sleeve valves any good? So thats what an L-Head is-Kevin ( P.S Havent heard anything about the “adibatic engine” lately)

I envision a gasoline engine with direct injection and high compression, similar to a diesel. Sort of a cross between diesel and stratified charge.

Near the end of the compression stroke the fuel injector will begin to inject the fuel toward the spark plug.
The spark plug ignites the fuel early in the injection period so the fuel burns gradually as it’s being injected.
Knock is avoided because a large amount of unburned fuel/air mix is not allowed to build up in the chamber.
Timing of spark and injection may be complex, but that’s what computers are for.

You can prop start an airplane engine like that(not going into to details,I dont encourage it)-Kevin

These guys have been getting a lot of attention lately. I got to check out their prototype at the SAE World Congress back in April:
http://www.scuderigroup.com/