Epitrochoidal Crankshafts in F1

[olefud]

I haven’t analyzed the dwell times, but these are often robbing Peter to pay Paul situations. If, in terms of degrees, there is more dwell time per degree at the bottom of the power stroke to allow blow down with only a few crank degrees movement, that means that this time comes out of another portion of the power stroke that is most likely under even greater cylinder pressure. To gain speed per degree would likely mean loss of mechanical advantage at the higher pressure portion of the stroke.

[Stivala]

I excuse myself for coming this late on this subject.
In my opinion this expansion cycle design will not be used in a F1 engine.
This is something that is dreamed about by F1 engine designers, this F1engine designer dream falls into the category of the cam less design which although a designer dream was never used in F1.

[langwadt]

I excuse myself for coming this late on this subject.
In my opinion this expansion cycle design will not be used in a F1 engine.
This is something that is dreamed about by F1 engine designers, this F1engine designer dream falls into the category of the cam less design which although a designer dream was never used in F1.

must use poppet valves, variable lift and or timing is not permitted, so there's no point in even trying a cam less design

[Brian.G]

There would be no improvements from using this system in any recip piston engine. The additional mechanical losses from the added bearing surfaces and gear contacts would more than offset any potential gains from improved combustion efficiency. With a high rpm F1 engine, this concept would present especially difficult problems, due to much higher masses that the rod bearing must deal with, the larger size needed for the rod big end, and the large, reversing dynamic forces that the phasing gears must accommodate.

I've seen lots of similar concepts. This is just a new twist on an old idea. But it offers no real improvement.

Agreed,

Brian,