You missed the most important point. The resonance frequency. It is easy to build a non-linear spring, and the time that springs break is long gone. You can see it in modern motorcycles 16.000 rpm is not a problem at all and these engines run easily for 40.000km without failure. The problem with larger displacements is that the valves get bigger and therefore naturally heavier, so you must increase the spings force, but by stiffening the spring you increase their resonance frequency to higher rpm so the springs starts to resonate when it really counts at high rpm. You can still overcome this effect to a degree by using two springs with different spring forces. There are roadcars that use this method. The 1st series of Golf GTI is such an example. The fun thing with the gas spring is that it has basically no mass and it can't resonate, or at least not in a rev range where it matters.

@snakeoilaudio

29 күн бұрын

oh that's interresting too. Do you know that when Toyota was active in F1 they even tested Desmotronic for their F1 engines. At the end they decided against Desmo but they played around with it. You can see a prototype in their facility in Cologne, Germany.

@themotorsportstory

27 күн бұрын

Yes, today's springs and metallurgy are much more advanced than back in the 80s, so the statement about breaking springs was in context of the F1 cars back then. They had some issues with springs breaking due to fatigue as well as heat but you are definitely correct that resonance can cause a spring failure also. I sort of glossed over this with the mention of valve bounce and resonance effects, but perhaps could have put more time into discussing resonance as a whole and it being a cause of total failure. I try to keep my videos easy to understand for a general audience and I wasn't sure I could get into this without the video becoming too long/too advanced for the average person. I didn't know that about Toyota playing around with Desmodromic valves, very interesting stuff! Thanks very much for the comment and for watching!

@vladimirzimonja8103

4 күн бұрын

Great solution. I know how 2 and 4 stroke combustion engines work but i didn't know about spring resonance and floating. Using a tank of nitrogen is great idea. For a race car. The regulator reminded me of the one i used on my airbrush compressor that my old man made out of a fridge compressor,a tank,valves,connectors,and most important,the regulator. It was the one with a glass lower part with a spring that sealed it when the compressor made enough pressure with of course enough strength to push the round plate down and seal it. We live we learn. Great video.

As a Miata driver, feel called out. Also as you are are reading this I'm trying to figure out how to put pneumatic valve springs into said Miata

@alexjohnward

29 күн бұрын

Find a cosworth V10 to put in there!

@themotorsportstory

29 күн бұрын

It's ok, I'm a fellow Miata enjoyer 😉 So if you ever get it working in your car let me know haha

@Birb_of_Judge

29 күн бұрын

@@themotorsportstory haha, First I'll try with regular springs. Until I Win the lottery, then I'll have a solution custom made. (And probably a few sets so others can enjoy it too

@sirhcsuiris

29 күн бұрын

@@Birb_of_Judge Just like my Mini S, the AC off button is the sport mode.

@Birb_of_Judge

28 күн бұрын

@@sirhcsuiris my Miata doesn't even have ac 😂

As a an automotive technician that was an excellent explanation.

@themotorsportstory

26 күн бұрын

Much appreciated, thank you!

that's why, once, during the Monza GP, BMW managed to reach 21000 rpm....during 3 laps (during the early 2000's) It works, it works perfectly but...better be gentle with it or your rear tyres will lock at 350kph (that's what happened to one of the Williams BMW pilots during this race, when his engine decided to quit the race...after 3 laps)

@themotorsportstory

26 күн бұрын

Ouch😂

Great video. Quality content, well edited.

I wish pneumatic valve springs were more common. They are so effective. They are used in MotoGP (Except Ducati) as well as F1. The MotoGP bikes have a small, probably carbon, tank and small compressor that pressurizes the valves. I'd love to see one of the new Dart Block 2JZ engines paired with a pneumatic valve head ran by timing gears. That could easily rev to over 15k. Joel Grannas money shifted his orange Supra and hit 12k, and everything was fine. It was a billet 2JZ though.

@ArneChristianRosenfeldt

29 күн бұрын

So for a road car the advantage is that I can ramp up the pressure with RPM? If you don’t race with displacement regulations, going above 12k gives you no power.

@9rjharper

29 күн бұрын

He is talking about race engines though. Or at least fun, fast street car engines. Dart is a manufacturer of aftermarket, high performance engine parts. And people enjoy trying new things and tinkering with machines. Increased rpm will give any displacement engine that can handle it and is designed for it, more horsepower. So even without a displacement rule, you can make more hp.

@ArneChristianRosenfeldt

29 күн бұрын

@@9rjharper flame front needs time to travel. Friction losses rise. Race cars don’t have torque converters, and shifts in a corner may send you flying. So pilots like the flexibility to rev beyond max power.

@silentbobfan32

29 күн бұрын

there is still the problem of piston speed. the average speed of a piston cant go above about 60mph, even in formula 1 engines. that is why they have such short strokes, down around 2" or 50mm to rev to 15k

@silentbobfan32

29 күн бұрын

​@@ArneChristianRosenfeldtlots of race cars have torque converters, and torque converters work fine with high rpm if they are built with that in mind, just look at what mclarren is doing with thier "single speed" supercar, which basically just uses a specially built torque converter as the transmission to go from 0mph to 250mph with 0 shifts. these engines are also tuned to male power until very high in the rev range, and because of the short stroke they lose less to friction than youd expect. flame front travel speed is also a bit of a myth in a highly tuned engine, the flame kernel is used to make a spike in pressure and cause the rest of the cylinder to burn at nearly the same time through what is esentially controlled detonation, similar to a diesel but using the spark plug to control the pressure spike rather than pure cylinder pressure and temperature

Just discovered your channel. Nice job on pneumatic valve springs. Looking forward to your presentations of other motorsport technologies.

What a great video! Excited to look through your catalog.

@themotorsportstory

26 күн бұрын

Thanks so much! Hope you find something else you enjoy too! I cover technical stuff like this but also have some videos more focused on history.

Cracking video with the perfect amount of details. 😀

@themotorsportstory

29 күн бұрын

Much appreciated, thank you!

Thanks for posting this video I’ve been trying to get a clear explanation on this for about a year now.

somebody get this man views 🙏🙏🙏

@georgekaiafas950

Ай бұрын

seriously this is awesome

@kwisin1337

Ай бұрын

Yes it is, share it with your group.

@themotorsportstory

29 күн бұрын

Haha thank you! I'm glad you enjoyed it!

@PANTHERBURNS

11 күн бұрын

Yeah this channel rules.

Very good content, thx for the video 👍

Wonderful explanation, thank you kindly! 👊🏼

@themotorsportstory

26 күн бұрын

Thanks so much!

He forgot to mention that like all metals, Valve springs have a 'Resonant Frequency' at which they begin to feedback the energy and fail. It also takes a specific time for the valve springs to do their job which limits the RPM they can achieve. The solution is being explored by Konesigegg with their 'Free Valve' engine which completely eliminates the camshaft and al other components of the Valve Train.

@AndriusKamarauskas

2 күн бұрын

And yet they failed to release product to the market ¯\_(ツ)_/¯

Awesome content and engineering theory!

@themotorsportstory

26 күн бұрын

Thanks, glad you enjoyed it!

First introduced by Renault in the Lotus. To be more precised, a Matra and Renault invention. Because this invention is stock and displayed in the Matra museum in France. Back then Matra was still this amazing engineering compagny, which had a great competitions history. Often forgotten nowadays. Matra had the advantages, to work in so many types of industries, which allowed them very excellent engineering in different domains.

Very cool, great video!

@themotorsportstory

26 күн бұрын

Thank you!

This is one of thise rare instances where reinventing the wheel actually happened and suceeded.

Good stuff!

@themotorsportstory

29 күн бұрын

Glad you enjoyed it

There is also a natural limit for steel springs. Stronger ones are heavier and so add mass to the valve they need to move. More mass -> more force needed -> bigger spring. Until you reach the limit. Also coil springs resonate. That’s the reason why you often see a large spring with a small one inside. They have different resonance frequencies and together both resonance peaks flatten out. Gas just behaves more ideal than bend iron. 😂

@themotorsportstory

26 күн бұрын

That's exactly it! Gas does just behave much better for this application😂

It was the mass of the valve spring that was eliminated, and they were massive to even try to keep timing geometry correct.

Great presentation. Keep it up

@themotorsportstory

29 күн бұрын

Thanks so much!

What if one would use Progressive wound springs when tuning a standard engine? This is an INSANE idea!

Interesting video there. But you don t say how much max rpm this new technology allowed Renault engines running in 1986. It would be an interesting fact to compare with other engine suppliers at the time it was introduced.

The base spring perch also needs reinforcement with higher rates. The pneumatic setup does not need it.

Thank you so much, bro! Best video ever about valves...

@themotorsportstory

27 күн бұрын

Glad you enjoyed it!

You skipped over whole aspect of pneumatic valve springs. Due to the geometry of how cam lobes open the valve, the power required to operate the cam as it moves thru opening the valve is almost perfectly inverse to the power required operate the valve.

Who knows? We might even see some solenoid actuators that function as valve springs, camshafts, and rocker arms to the point of replacing all three simultaneously, similar to what Koenigsegg is doing with its freevalve technology.

Nice video, good animation. But why is there a rocker arm in the animation when the camshaft is directly above the valves?

@9rjharper

29 күн бұрын

It’s a follower. A lot of overhead cam engines use followers like shown in the animation.

@9rjharper

29 күн бұрын

Among other things, they allow a higher (or lower depending on the location) lift ratio than you can get with the cam directly over the valve.

@MrEdmr2

29 күн бұрын

I understand, but in motorsport you want to eliminate as much moving parts (and weight) as possible, so it doesnt make sense especcialy when youre trying to chase high rpm’s.

@themotorsportstory

26 күн бұрын

Glad you enjoyed it! The reply from 9rjharper is correct.

Perfect sound effect at 3:15

@themotorsportstory

26 күн бұрын

😂

🤯🤯🤯 omg that is extraordinary to think such an incredible idea came (renault of all teams) by dumping springs for pneumatic has completely changed f1 forever i must congratulate you tms in making this video and have a great day bye now😊.

@BurningmonkeyGTR

Ай бұрын

You say Renault of all teams, but you have to remember that Renault invented the turbocharger, supercharger, driveshaft and mass damper, introduced the turbo in F1, have won many titles as an engine supplier and 2 as a constructor, and won the first ever grand prix

@milfordh.mercado2787

Ай бұрын

@BurningmonkeyGTR oops i forgot how innovative renault was in history and one more thing to say is do you know of renault van with f1 engine.

@BurningmonkeyGTR

Ай бұрын

@@milfordh.mercado2787 you mean the Espace F1?

@themotorsportstory

29 күн бұрын

Glad you enjoyed it! Thanks as always for watching!

@milfordh.mercado2787

29 күн бұрын

@themotorsportstory 😃😃😃 A big thanks to you sir as usual wanting for part 2 of odd race cars in the future bye now.

With a reasonably large accumulation volume, you can also have "constant rate" pneumatic springs.

@rogerking7258

29 күн бұрын

Or at least "near constant rate".

@themotorsportstory

26 күн бұрын

Yes you could get close to "constant" with a large enough volume

Courtesy comment for an excellent video!

They fill them with Nitrogen because its non corrosive to the seal compound and Nitrogen Molecules are larger than Oxygen Molecules so they can't get past the seal tolerances easily.

I honestly had no idea this was a thing. Iv only heard of koenigseggs innovation to valves

What's about the desmodromic engine from Ducati? Wouldn't it work for F1 too? Or any racecar?

Great stuff

someday someone will come up with a clean two stroke engine architecture and then F1 power will double and F1 cars will sound absolutely insane. if you think petrol engines are going to be replaced by electric anytime soon then I've got a bridge to sell you too.

@dpenduro8950

29 күн бұрын

I hope so I’m a huge fan of all different style 2 strokes especially rotary valved 2 strokes

I would love to know more about the seals. Are they lubricated somehow?

@themotorsportstory

26 күн бұрын

To be honest, I couldn't find much info on this. I did find a few sources describing how it is difficult to keep oil out of them, so it's possible that engine oil might lubricate them, but I'm not 100% sure. Also possible they have their own lubricant

Why they didn’t use rotary valves? Gretings✌🏻

@thiswillprobhrt

28 күн бұрын

Friction\heat and sealing difficulties...

marine 2 strokes which run at less then 100rpm also use pneumatic valve springs

@themotorsportstory

29 күн бұрын

Interesting, didn't know that! Thanks for sharing!

@gothicpagan.666

29 күн бұрын

Poppet valves on a two stroke?

@themotorsportstory

29 күн бұрын

@gothicpagan.666 I'm interested to know more as well. I've never seen a two stroke with poppet valves but I'm not as familiar with the world of two strokes in general.

@themotorsportstory

29 күн бұрын

Doing some searching I found this: kzread.info/dash/bejne/iXqd1ttphMaXmtY.htmlsi=Narkbr3DkLltdbWx Looks like they're used on an exhaust valve on this marine engine. Fascinating!

@thinfourth

29 күн бұрын

@@themotorsportstory RTA-flex goes further and has binned the camshaft for opening the exhaust valves

I just want to say I appreciate your video titles. You give a vague hook followed by exactly what you're going to explain. Clickbaiters should learn from this.

@themotorsportstory

26 күн бұрын

Thanks, I really appreciate this as it's exactly what I'm trying to do! The way KZread works, you have to hook people in with something or your video won't get any views, but it's never my intention to deceive anybody or bait them with something that isn't actually in the video.

Rx8 mentioned 🎉🎉🎉🎉🎉🎉

@themotorsportstory

26 күн бұрын

🔻

Good video, but don't apologize for the "complex math". It isn't, and if people don't get it, too bad. I honestly didn't realize that this was the level of simplicity that Renault had come up with. I thought that the opening of each valve was controlled with a pneumatic solenoid rather than just replacing the spring. I thought with a pneumatic solenoid the benefits would be major: 1. INFINITE valve timing all adjustable with computer, and 2. Simplified engine design with no camshaft requirement.

@themotorsportstory

27 күн бұрын

Thank you, glad you enjoyed it! I'm not positive but I believe that F1 cars can't have variable valve timing per the rules which might be why there is no computer control.

Im not sure if your theory about gas is completely correct, that you can just assume that one side of the equation has very small variations and can be set as a constant, because as pressure increases so does temperature and vice versa when decompressing. Setting temperature as a constant throughout the cycle of compression and decompression would completely disregard this fact. Its basically disregarding mechanical work that happends when you compress a chamber of gas but im not sure how this impacts the equation and how the valve is pressing against the camshaft over its travel

@themotorsportstory

27 күн бұрын

Thanks for the comment! You're absolutely correct that the temperature will change. The assumption wasn't made to ignore that fact but more to simplify the equation to a point where it could be compared to a regular spring which only has the variables of spring force and distance of compression or extension; which can be compared to pressure and volume of the pneumatic spring. Regardless of the temperature changing, the progressive curve will still be there, it just might look more flat or more sloped depending on what the numbers work out to. I probably could have done a better job of justifying the assumptions in the video, but the main idea was to illustrate that progressive curve in as simple of a way as possible for people who might not have much of an understanding of math or physics.

@easybuckets9740

25 күн бұрын

@@themotorsportstory Actually when I took a closer look at the numbers it seems like the pressure will increase more exponentially when you have temperature as variable so the original calculation actually underestimates the effect. Anyways, great video and thanks for the answer!

@themotorsportstory

23 күн бұрын

@@easybuckets9740 Interesting! Thanks for looking into that and I'm glad you enjoyed the video!

Yup variable Timing n kinetic energy and 1600 kw n sodium filled valves springless pneumatic gas for cooling 200 degrees cooler

Bro just like, use nitrous oxide for the valve spring gas so if it leaks the engine can be like "Oh this is fine"

Makes me wonder how honda and other motorcycle manufacturer had engines in the 90s that reved to 18-20k

@thiswillprobhrt

28 күн бұрын

Less valvetrain inertia.

Was it not Brian Hart that was first to ditch valve springs in favour on pneumatic valve control

@rogerking7258

29 күн бұрын

No, in fact I remember his brother telling me they had managed to rev to 15,000rpm with conventional springs, which he thought might be a record.

@gothicpagan.666

29 күн бұрын

@@rogerking7258 Sounds a bit optimistic. Were talking late 70's early 80's here. 420R would run out of breath by 11.5k even with those 328 Deg cams that Kent? came out with in the late 80's Never had my hands on a 415T, though they were only good for 680ish brake in the Shadow. Wish Brian had wrighten a book, all that knowledge and great stories now lost😞

Had these in marine engines for 40 years

When you get stranded on the side of the road because the nitrogen tank is depleted, that is when you truly ran out of gas.

Pneumatic Valve -Springs- 😉

Koenigsegg: freevalve. Renault: pneumatic-spring valve.

Why not use Desmodromic valve train?

but wait why isn't this kind of technology being used in cars? are they just too expensive or more complex than the simple spring valves?

Wouldn't spring compression energy be given back when it expands?

@rogerking7258

29 күн бұрын

Yes, in theory, but in reality you're also dealing with increased friction which will lead to an energy loss, plus severely increased wear on the rubbing surfaces of cam and follower.

@themotorsportstory

29 күн бұрын

Roger's reply nailed it! I probably could have made this more clear in the video, but was trying to keep everything at a relatively elementary level.

@9rjharper

29 күн бұрын

Besides what the other person explained, the valve train also has inertia, so when the cam is on the closing side of the lobe, the valve spring isn’t push back with as much force as it was when opening. If you know what valve float is, imagine that (except not necessarily to the extent of being completely off the lobe).

Desmo spring the best

Great vid! I'm amazed pneumatic valves haven't got the attention they deserved over the years. They're comparable to ground effects as far as their importance to the sport in my stoned opinion 🤔

@themotorsportstory

26 күн бұрын

Thank you! Yeah, there isn't much info out there on them by comparison which might be one reason. I suppose F1 teams don't want to give out too much design info

So why not just use progressive valve springs. I understand it still has the other flaws but wouldnt a progressive spring be better than a linear?

❤❤

Desmodromic valves would do away with the need for a nitrogen tank. There's no spring with this system either.

Here is the problem with F1. Due to the rev cap there is very little reason to spend money on the engine top-end. Otherwise we could possibly see the koenisegg “freevalve” tech in f1 engines.

And funny thing after all this is all human kind wants to see v8 and v10 back in f1

Nitrogen in frame n tires etc

Running 600 degrees chts but with sodium filled valves goes down to 400 etc 420

show me MAGNETIC VALVES :P

I thought the "most advanced and technological engines in the world" would use fully electronic valves instead of mechanical (well OK, pneumatic) ones, so they would have full control on the valve timings for all the driving situations they encounter. Not reliable enough ? Not fast enough for F1 engine speeds ? Not worth it ?

For how long does these engines running at 15000 rpm last. If lucky to the of the race. Most layman do not realize that all “race” engines are not expected to last 100 tho miles or 200 tho miles. In other words metal breaks, just a matter when. I’ll stick to my ole Honda put, put.

I believe renault were able to reach over 20000 rpm in testing.

@13thdukeofwybourne69

29 күн бұрын

There was an _entire_ era in F1 between 1989 and 2006 when _most_ of the V10 engines span up to around 20,000 rpm in qualifying trim. I would say it was the peak F1 engine era. The F1 regulatory body killed them off. The Bastards.

I would glady top off with n2 every tank of fuel if 18,000rpm was the payoff.

@themotorsportstory

26 күн бұрын

😂 I commend the dedication

F1 valve trains dont use rocker arms ! like all modern overhead cam engines they use cam buckets - esentialy pressing directly down on the valves -

@themotorsportstory

26 күн бұрын

Some of them do/did. Here's a paper showing some of Honda's designs that incorporated them. Referred to as "finger-followers" www.f1-forecast.com/pdf/F1-Files/Honda/F1-SP2_09e.pdf Here's a video of a former F1 engineer going over the parts of the design that includes a finger-follower: kzread.info/dash/bejne/oo57yqmYZJaXnqw.html Again, my animation was based on a combination of different design diagrams I could find, some F1, some MotoGP bikes

Great video. However, (more) attention should have been given to the Renault 3.5Liter v10 (RS2 more than the RS1) that made the technology staple. Please keep in mind that it was during this period that John Barnards 639/640 ushered in the semi-automatic gearbox with paddle shifters and electromagnetic clitch.

@themotorsportstory

26 күн бұрын

Glad you liked the video! Interesting info on the semi-automatic gearbox origins!

Trabant drivers feeling under-represented..

@themotorsportstory

26 күн бұрын

😂 I love the Trabant, such a strange and unique little car. The channel "Aging Wheels" here on KZread has some great vids on his.

Another technology that could not be transferred to everyday cars, making racing every year less useful.

Rotary valves.

@jonv.6213

7 күн бұрын

I was just about to mention those

There is no need for the rocker in your schematics

@themotorsportstory

29 күн бұрын

No it's not necessarily needed if I had shown a traditional hydraulic bucket-type lifter instead. But many F1 cars use a finger-follower (rocker arm) design, so I figured I would add it.

@rogerking7258

29 күн бұрын

@@themotorsportstory Agreed!

@user-oo6lm1un6m

29 күн бұрын

It is called a finger-follower and yes it is needed. Without it the cam-lobe would put unnecessary side-load on the valve stem. All F1 and MotoGP engines that run pneumatic valve-trains use finger-followers. You can’t run this system without it.

@9rjharper

29 күн бұрын

A lot of valve trains use followers. They also allow different lift ratios (and you can even change the profile of the follower to change valve event timing slightly).

Spring force explanation made no sense.

SPEAK METRIC, dont insult the eng who designed it and confuse the WORLD !

More like mechanical abominations.

This is super interesting, great video!

@themotorsportstory

26 күн бұрын

Thank you!

Keoneggseg?

Great stuff