What could replace timing chains/belts in an ICE engine?

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Please feel free to flame me, but my mind is thinking mechanicals today. I know timing belts and chains generally do an excellent job doing what they're supposed to but what could be used in the place of them, could the cam shaft be connected to a dedicated electric motor and run by all the ECM parameters , or would it never be accurate enough to time all the valves correctly, as I write this I'm realizing that a timing chain/belt driven by the crank will probably never go away as it makes the most sense. I know engineer types are probably laughing at me but I was just speculating
 
I was running this by a co worker today and he thinks BMW has already tried this , or something vaguely similar 🙄
 
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Interesting, I didn't even think of the elimination of the camshaft itself, just how it's being driven .. Thanks, good read.
 
there's wankel rotary engines
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He made an updated video with the announcement of the Koenigsegg Gemera, pretty neat concept, having two exhaust valves and being able to use one to go straight to the exhaust and another to the turbo, no need for an external waste gate when the exhaust valve can be the waste gate.
 
While they may eliminate camshafts at some point, I just can't see keeping the cam(s) and driving them via a servo or something while ditching belts/chains/gears. Higher torque, ~3200rpm (cam turns 1/2 the speed of the crank) servo motors tend to be quite large as well.
 
When I rebuilt my Olds 350 rocket engine I had the option to replace the timing chain with a gear set. I believe the downside is noise.
 
Take a look at some motorcycle engine designs to see some really odd stuff, like worm gear drive for example.
The old 300 cu. in. Ford straight six had bevel gears to drive the cam, the lower one had plastic teeth to reduce whine. It would wear out after about 400,000 miles!
 
Originally Posted by JohnG
The old 300 cu. in. Ford straight six had bevel gears to drive the cam, the lower one had plastic teeth to reduce whine. It would wear out after about 400,000 miles!


The cam gear on 300s was changed to plastic in the 1980s, ostensibly to reduce noise . Some fail at 150k miles, some last longer.
 
The first two cars I owned (see below) both used gears to drive the camshafts. No maintenance needed and no problems with either drive. The Chevy used "Bakelite" phenolic thermoset plastic for the driven gear, I think. I don't know what it was in the Subaru.

No problems with the original chain drive in the Mazda, either.
 
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The Tucker prototype had a hydraulic actuated valve design. The Tucker "589" had a bunch of problems and was replaced with the Franklin engine converted to water cooling.
 
bigger diesel engines(and I think to a point the smaller ones found in 1-ton pickups - the PSD/CTD/DMax) use gears to turn their cams, Toyota is also using a gearbox on their diesel V8.

Ducati is the only mass-market firm that scrapped valve springs and lifters with a desmodromic system.
 
Back in the day, gears were used to drive camshafts directly off the crank. I wish they would bring that design back because it is very quiet and extremely reliable. Not feasible for OHC designs though... pushrod motors mostly.
 
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