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Underdrive Cam Sprockets

Like underdrive pulleys but for the camshafts
  [vote for,

An engine's valvetrain eats up alot of power compressing the valvesprings so much and grinding against the lifters or followers. So just reduce the speed of the camshaft for huge power gains!
davidcreede, Jul 22 2003


silverstormer, Jul 22 2003

       Wouldn't this require twice the number of, even spikier, cam lobes?
nick3, Jul 22 2003

       Or better yet, just eliminate the cams altogether. And the cylinders, Infinite power gain!
RayfordSteele, Jul 22 2003

       I was trying to remember the theme to the movie "Wierd Science", but then I realized this was just "Bad Science". Oh well.
Cedar Park, Jul 22 2003

       //reduce the speed of the camshafts// - If I understand the purpose of camshafts correctly (I'm pretty sure I do), then you can't do this without seriously damaging the valves in an interference-design engine, which is to say most engines made today. Slowing the camshaft would cause the valves to not match the speed of the pistons, meaning they'd collide every few revs when they match the wrong way.
tekym, Jul 22 2003

       The camshaft has to turn at a certain speed in relation to the crankshaft (once for every two), that's how the 4-cycle engine works. There are several companies that are trying to make a camshaft-less engine, by making all the valves computer controlled. Cadillac may be the first out the door with such an engine, as they've already shown several test engines, but I know that BMW is also working on the technology.   

       The big issue is that every valve has to move 41 times persecond, while the engine is spinning at 5,000 RPM. Multiply that by a modest 12 valves, and that's a whole lot of high tension parts moving very quickly.   

       Perhaps a better way to remove friction would be to introduce rollers on the lifters or rocker-arms riding the camshaft. This has also already been done in performance engines.
Payback, Jul 23 2003

       Desmodromic engines use the cam instead of springs to close the valves. They are finicky to adjust, and noisy, but can be found on Ducati motorcycles. The trouble so far with servos is durability and current capacity of the charging systems. The manufacturers are probably going to switch to 42 volt systems soon. 2 strokes are polluters. Especially in the water.
moPuddin, Jul 23 2003

       is this guy for real!!!!! i think m.i.t is looking for professers
mini1, Oct 13 2003

       Why not just overdrive the crank? That would effectively underdrive all other engine pulleys!   

BuffMyRadius, Nov 14 2011


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