Chainless/beltless Engine? (2009, hybrid, gas, 1999)

[StealthRabbit]

Originally Posted by Lux Hauler

Many engines (diesels in particular) exist that do not use belts or chains but instead contact gearing. There is also quite an aftermarket to convert belt/chain systems to gear sets. These gear systems are good for the life of the engine. Why don't we see more? Well... they are relatively noisy, more costly and TOO reliable!
...

Yes, and not too NEW of a technology... Studebaker was ruling the performance engines of the 50's with a gear driven V8.

I will stick with CRANK windows, and 'push starts' with dead batteries (I work in high tech, no need to ruin my hobbies of vintage engines).

I do wish my VW diesel 'INTERFERENCE engines' had a more ROBUST solution than a belt... But I only have 52 HP, so none to spare on gear train, and NO THANKS to an electronic actuated Valve

All things are possible, not all are reasonable.

[burdell]

Originally Posted by StealthRabbit

Yes, and not too NEW of a technology... Studebaker was ruling the performance engines of the 50's with a gear driven V8.

I will stick with CRANK windows, and 'push starts' with dead batteries (I work in high tech, no need to ruin my hobbies of vintage engines).

I do wish my VW diesel 'INTERFERENCE engines' had a more ROBUST solution than a belt... But I only have 52 HP, so none to spare on gear train, and NO THANKS to an electronic actuated Valve

All things are possible, not all are reasonable.

There's a few problems with gears. With overhead cam engines, if the head and/or block surfaces are refaced you're going to need the availability of different size gears when reassembling. There's also quite a bit of torsional winding/unwinding in a camshaft and some engine builders believe a chain or belt isolates that from the crank.

[Lux Hauler]

Originally Posted by burdell

There's a few problems with gears. With overhead cam engines, if the head and/or block surfaces are refaced you're going to need the availability of different size gears when reassembling.

True, however this could be resolved with headgaskets available in different thicknesses or adjustable gears to set the lash. Just think, a miniature hypoid gear set allowing 90* transmission, lash could be set simply by shimming.

Originally Posted by burdell

There's also quite a bit of torsional winding/unwinding in a camshaft and some engine builders believe a chain or belt isolates that from the crank.

Another good point however this is really a function of the materials and tolerances used, I.E. $$$.

[burdell]

[quote=Lux Hauler;30838579] True, however this could be resolved with headgaskets available in different thicknesses or adjustable gears to set the lash. Just think, a miniature hypoid gear set allowing 90* transmission, lash could be set simply by shimming.[/QUOTYE]

And lose compression?

Originally Posted by Lux Hauler

Another good point however this is really a function of the materials and tolerances used, I.E. $$$.

Oh, I don't think we're close to learning every way there is to skin a cat. Just because no one's yet built a reliable, cost competitive electric valve actuator that's not a power hog doesn't mean it won't happen. After all, how many race engineers 25 years ago would have told you diesels would become the 'hot ticket' for endurance racing? And one thing's for sure, it's a lot cheaper to burn a chip than to manufacture gear sets, hypoid or otherwise.

[Lux Hauler]

Originally Posted by burdell

And lose compression?

Oh, I don't think we're close to learning every way there is to skin a cat. Just because no one's yet built a reliable, cost competitive electric valve actuator that's not a power hog doesn't mean it won't happen. After all, how many race engineers 25 years ago would have told you diesels would become the 'hot ticket' for endurance racing? And one thing's for sure, it's a lot cheaper to burn a chip than to manufacture gear sets, hypoid or otherwise.

A head gasket thickness to accommodate for the milled distance on block/head would result in 0 net change to the cylinder volume. Maybe some slight variation based on head chamber geometries, or am I missing something here? Another solution would be to take a packaged 90* gear set, attach it to the end of the cam and have the drive shaft on the gear set telescopic or some other means of allowing a range of movement. At this point cost is becoming a concern.

I definitely agree that complete electronic valve control is a viable technology however the passivation, packaging and thermal resistance capabilities of current electronics (commercially available) are just not to the point where I would call them “highly reliable”. True, that a burnt up component is cheaper than a failed mechanical item but have fun diagnosing and finding the former.

[Frihed89]

I'm not sure if all this is possible, but technological change in passenger vehicles is painfully slow, compared to what is being done in Formula one and GT endurance racing, Lemans-style. For example, double overhead camshafts were common in Formula one from the 30s-on. They didn't arrive in passenger cars on a grand scale until the late 1980s. The rate of change has been faster in recent decades, but how many passenger cars automatic gear shifting (not automatic transmissions), and so on?

Amazingly, there has been some recent "backward technology penetration" from passenger cars to sports racing cars, to wit 4-wheel drive and hybrid engines, both of which are featured on the cars (Audis) that won the 2013 Lemans 24 hour endurance race.

So, who knows?

[burdell]

Originally Posted by Liquid Sword

A head gasket thickness to accommodate for the milled distance on block/head would result in 0 net change to the cylinder volume. Maybe some slight variation based on head chamber geometries, or am I missing something here? Another solution would be to take a packaged 90* gear set, attach it to the end of the cam and have the drive shaft on the gear set telescopic or some other means of allowing a range of movement. At this point cost is becoming a concern.

Nah, I just tend to oppose loss of compression, even if it represents o net change

Originally Posted by Liquid Sword

I definitely agree that complete electronic valve control is a viable technology however the passivation, packaging and thermal resistance capabilities of current electronics (commercially available) are just not to the point where I would call them “highly reliable”. True, that a burnt up component is cheaper than a failed mechanical item but have fun diagnosing and finding the former.

Oh, I don't think we're 'there' yet, I just think the ability to make the same engine perform as a balloon-foot driven econo unit or a high revving screamer on demand is too interesting a prospect to give up on. We successfully control electronically intake/exhaust tract lengths, valve timing would be a logical progression.

[harhar]

I don't know if anyone has mentioned this but all new Priuses' accessories are beltless.

It has an internal timing chain though.

[burdell]

Originally Posted by Frihed89

I'm not sure if all this is possible, but technological change in passenger vehicles is painfully slow, compared to what is being done in Formula one and GT endurance racing, Lemans-style. For example, double overhead camshafts were common in Formula one from the 30s-on. They didn't arrive in passenger cars on a grand scale until the late 1980s. The rate of change has been faster in recent decades, but how many passenger cars automatic gear shifting (not automatic transmissions), and so on?

Don't forget though in some cases passenger cars have technologies that are banned in F1, ABS and traction control come quickly to mind. I'm not sure but I wonder if the magnetic fluid shock absorber control featured on some production cars would be allowed in F1?

Originally Posted by Frihed89

Amazingly, there has been some recent "backward technology penetration" from passenger cars to sports racing cars, to wit 4-wheel drive and hybrid engines, both of which are featured on the cars (Audis) that won the 2013 Lemans 24 hour endurance race.

So, who knows?

That's what keeps it interesting, you never know what will happen next. I well remember when everyone was working hard to block air from flowing under the car and Colin Chapman took the exact opposite approach

[burdell]

Originally Posted by harhar

I don't know if anyone has mentioned this but all new Priuses' accessories are beltless.

It has an internal timing chain though.

Gear driven or?