The Hawker Tempest was the fastest piston powered airplane ever made, it had a sleeve valve engine. It was made obsolete, by the Me 262 and other jet engined fighters, But it's engine was the ultimate piston aircraft engine. Then piston engines became something for inexpensive planes, but why has the sleeve valve not undergone further development as a sports car engine?
2007-10-01 15:31:23 · 5 answers · asked by Cowboy C 4 in Cars & Transportation ➔ Aircraft
The main problem was the oil consumption, since a very tight seal required close tolerances that in turn called for very precise lubrication.
As Wikipedia states (see link) if one wants to do away with poppet valves, and is willing to accept a very wide lubricated area, one might as well go all the way and go with a Wankel rotary engine which entirely eliminates the need for valve and thus timing gearing.
Note that military engines do not have to be certified the way civilian aero engine need be, this in turn makes the process of introducing any change in an engine design extraordinarily expensive, hence general aviation piston engines are rather crude (but proven) design.
For automotive engines, one of the concern is the economy of scale: it is pointless to make an engine, to invest in all the development cost, if only a handful are produced. And it is pointless to make an engine that is meant for a wide distribution unless the cost of the final product is attractive, and that the maintenance expertise is properly widespread. So again, innovation tends to be introduced very slowly.
And you cannot count on auto racing to act as a test bench for such innovations, as the rules there are often actually meant to limit how innovative one can be...
2007-10-02 08:01:32 · answer #1 · answered by Vincent G 7 · 0⤊ 0⤋
i like to call them the two creation memories of Genesis the 1st tale which starts Genesis a million and ends Genesis 2:3 the 2d tale starts with Genesis 2:4 and keeps onward. on the tip of Genesis a million:27 it states that God created the two guy and lady which gave upward thrust to the perception that guy and lady have been created on an identical time interior an identical way wherein the guy replaced into Adam and since the story is going the female replaced into Lilith. yet of direction you will desire to comprehend that the Lilith tale is basically that a narrative in fact the Hebrews did no longer even supply her a acceptance the call originated latter on however the Lilith tale is folklore. The Lilith tale began for the period of the Babylonian exile of the Jews in spite of the undeniable fact that it would evolve for the period of the middle an prolonged time in Europe.
2016-10-10 03:35:21 · answer #2 · answered by Anonymous · 0⤊ 0⤋
this has been tried and failed miserablly mainly due to cost they ran a steel sleeve in a aluminum block and due to the differences in cooling the engine was subject to failure within 30,000-40,000 miles
2007-10-04 15:29:50 · answer #3 · answered by tbone19622 2 · 0⤊ 0⤋
it is a good suggestion. perhaps someone would take steps to implement it.
2007-10-01 15:40:39 · answer #4 · answered by jimmybond 6 · 1⤊ 0⤋
http://en.wikipedia.org/wiki/Sleeve_valve
http://www.a-car.com/valves/sleeve.html
2007-10-01 15:53:40 · answer #5 · answered by tronary 7 · 0⤊ 0⤋