had a good chuckle when he explained that part. "why the hell would they discard it?" "oh." i honestly thought it was a genius space and weight saving. totally forgetting that someone's actually driving it.

Not sure why we are getting excited about the oil running through the chassis to the oil cooler. Pretty much every race car of that period did that. Only stopped happening when the sport moved to monocoque chassis'

@@psk5746 mass-production motorbikes also, eg. some Buells used the frame for the fuel tank and (I think?) the swingarm for the oil tank

@@jsleeio true. Clever stuff. Quite like those bikes, even though I'm not a fan of the engine choice

My 450 dirt bike uses the frame as an oil tank... Didn't know in the beginning and burned my hand on it 😂

Insane when you put it that way

Definitely not arguably..

Thats basically all what they do, mercedes not only makes cars but also trucks, bus, bulletproof cars.......

Unless you are a child, that's good news for you I'd say.

Well I'm a BIT underweight, I'm only 3 kg heavier

Actually, a can would hold your weight, if you were able to apply the pressure evenly. The cylindrical form is key there.

@@noneofyourbusiness4294 In real life standing on a soda can and certainly in real life in the frame of a race car pressure is never applied evenly. In real life, thin world tubes are subject to buckling instabilities. To close approximation, thin wall tubes of the same external dimensions differing only in wall thickness will exhibit the same stiffness until the point the wall buckles. pressurizing the tubes isn't some afterthought or just a check for leaks, It is fundamental to the strength of the frame.

@@bengriffin4027 the nitrogen is still a gas though so it's compessible. even if it may help resist buckling a bit, the amount of gas displaced when a tube collapses only raises the gas pressure in the entire frame by a bit. Don't forget soda can's are filled for more than 90% with an incompressible liquid meaning a small change in internal vollume greatly compresses the tiny bit of gas at the top, proportionally speaking. The Atlas rocket was also filled with liquid propellants and when these propellants were drained from the tanks as the rocket went up, the weight of the rocket also decreased so the airframe was less stressed allowing the airframe to better support itself. Besides that, the propellant tanks had different length/diameter proportions compared to the 917 frame which allowed them to act more like a balloon. (same goes for the soda can)

Lets add a large impact to said full can of coke.... Not only does it crack or buckle... It will blow out significantly.

@@ddewaard3265 Indeed. The compressibility you raise is a very good point, and even if that were not the hypothesis-killer it clearly is, the soda can analogy has another flaw: the relative wall thickness of a soda can (as a proportion of tube *diameter* ) is several orders of magnitude less than in a chassis tube of maybe 16 to 20 OD x 2.0 wall. To provide meaningful anti-buckling support in the latter case would require ridiculously high gas pressures, which would cause the elements which were right-sized for tension forces past their failure point. In any case, the valves for filling the tubing with gas (which is generally understood in the engineering community to have been air rather than nitrogen in the case of these cars) were nothing more than conventional Schraeder valves, hence completely unable to hold the very high pressures anti-buckling would require.

Feedback noted, thanks for commenting - glad you liked it!

Yes would be a help. I just convert to kph in my head . Here : mph to kph 10 mph = 16.1 kph 1.6kph to 1mph

62.xxx mph is 100kph

@@Driver61 if you are keen to receive feedback, i kinda wanted to close the video halfway because the way you edited your speech, you didnt leave ANY space at all, its like reading a sentence without commas or periods, it felt weird, also, this could be just be me, but the pace is also weird, it goes like this "but not every sentence NEEDS to have HIGHLIGHTED wordsFOLLOWED byfastwordsthatendin s l o w w o r d sONLY to not LEAVE any space BETWEEN senten c e s" Tl:dr: a small break here and there, in my opinion, would make it sound a lot more natural. Edit: i did enjoyed the video though, excelent investigation, presentation and footage (:

and put things in lbs because I don't know kilos

Lol

I dislike that I liked this comment

Wat?

haha nitrogen go brrrr

Oh shit! High IQ stuff here!

hehehe good one

*going fuckoff fast on the straight with the sky in the rear mirror* Suddenly the pressure in the chassis starts dropping...

Bet the drivers paid most attention to that gauge

Not ridiculous at all. The same basic system (except with compressed air) is used in many tubular structures that rely on weld integrity for their strength - crane and drag line booms, for a start.

Actually...aeroplanes have this too (sort off)

They could have filled it with helium and it would have been even lighter.😂

@@tanmayta9131 Yeah, some gases are reactive/explosive

@@RacingLegendss Yes, but helium doesn't react or explode cause it is inert.🙂

The car flew around the track literally and figuratively

@@getnaenaed4222 that’s true hahahaha

Yea agreed! Love these videos.

Agreed that transition was impressive. Lol

He’s been getting real good at it, his last 3 videos all had super smooth sponsor transistions

And it was quick, to the point, and something actually cool instead of some of the obnnoxious garbage most sponsors tend to be [*cough* bRiLlIaNt *cough*]

@@camillecirrus3977 😂

almost felt like the entire video was done for this sponsor lol

I would never!

That was before he lost vision on one of his eyes, it was when he was racing in F1 at Clemont-ferrand when he got involved in a crash.

Probably people who read...

so it was a stone that flicked up into his visor from the lotus in front that ended his career? :O oh yeh he also set the fastest ever lap on the targa florio. record never broken.

marko in 72... kzfaq.info/get/bejne/pqyPoqlev7PMdGQ.html

Valentino Rossi

That reminds me of a joke. There's a car accident accident and someone shouts out "is there a doctor around here? It looks like the driver is going to die!" Someone says "I'm a doctor of philosophy- everybody dies!"

good one, even though he is a doctor in law.

@@oxcart4172 I don't understand

@@cpawel if u have to explain a joke to someone they're not going to think it's funny.

Putting the 1000 horsepower engine, in the most fragile chassis possible and doing fuck all about the aerodynamics however was not.

@@paulzapodeanu9407 They debugged it eventually. Thank the insects for showing them where the flow was separated.

SIMPLE???

@@craigykart Yes, but maybe test the car BEFORE the race.

Maybe helium would of added lightness

Do you do your torsional test your solar car chassis? Do you do them in autoclave or out of autoclave

As an engineer, I like this kind of details.

@@Jacob-W-5570 I actually thought it was a neat idea as well when I saw an engine cutout at the Porsche museum in Stuttgart. Definetly worth a visit if your close by. Though the Mercedes museum in the same city is much, much better.

I am happy you mentioned that. It is my assertion that taking the drive at the minimum first degree node of flex allowed the use of smaller crank bearings resulting less internal drag on the crankshaft. I.e. less parasite engine drag allowing the power that would be lost to drag on the crank to be used to propel the car.

It is still considered a flat 12, just not a boxer

True on the center power take-off on the engine.....and here's another 917 tidbit......the mating gears have a "hunting" tooth.....one gear does not have the same number of teeth as the mating gear...so the "Same-two" gear teeth don't mesh with every revolution. So an interesting question emerges.....when you see the RPM of this engine, is it the crankshaft speed or the slightly different output shaft ( clutch) speed......oops .....time's up. Cheers !!!

Great information! Can you please share the source with us? Book, magazine, journal? I would like to learn more about this history.

Interestingly, in a recent interview the other Porsche works driver present, Kurt Ahrens (also the winner of that 1969 Austrian grand prix with Jo Siffert), says it was basically him who came up with the idea, which would have to do with his family business, a metal-selling/scrapping company, in which he was constantly playing around with scrap as a kid, making his own cars. He was passing through the formula classes for Brabham, battling in Formula 2 often successfully with Clark, Hill, Rindt, Ickx... while being his own mechanic as a privateer (financed by his family business), and was known for having enormous mechanical empathy with the cars, the kind of guy who'd notice right away that the rear left wheel is slightly out of alignment or that the dampers were on their way out, and would have an idea how to fix it immediately; also he never crashed a single car during a race, known as a very rational and disciplined driver, so he was hired by Porsche to help with 917 development, a difficult job he was extremely well suited for. He suggested to the engineers to get some aluminium sheet from the hardware store in nearby Knittelfeld he had noticed on the way, and simply sticking it to the rear to see what that would do, the kind of thing he'd do to his own car; and it was applied that same day (perhaps after coming up with it independently after considering the fly-splatter-pattern, who knows); the brits ran with the story ever since. He's one of the more humble, shy and down-to-earth characters in racing, certainly not into fame and recognition - actually turning down driving F1 for Brabham after one race as he figured, this F1 circus with worldwide races wouldn't allow him to be with his family and the business anymore, and he's quite rare to give interviews. He says he asked Piech and Peter Falk soon after the 917 story if he should offer a correction to that story to the public, but it was suggested after a bit of quiet consideration for him to keep quiet, as that story would play better with the international audience if it were the british, making the 917 a more international project so to speak... I would say, that would be entirely in line with what is known about Piech and his strategic mind. David Piper who also partook in in that Austria 1969 race confirms that story. Oh, and the other guy's name is spelled Willi Kauhsen, if someone wants to look him up. If he had told that sort of story, I probably wouldn't believe a word, he's a great character and absolutely entertaining to listen to, but definitely a story-teller never shy to "emphasize" his own role in whatever happened. Ahrens is a very different character. In fact, it doesn't matter too much who actually came up with it first - they had a lot of brilliant and highly motivated minds pulling all-nighters and working their ass off to get this car right.

@@decnet100where do you got this info from. I guess a certain podcast maybe? Alte Schule?

@@z33r0now3 Sure, the interview with Ahrens there is the longest that he has given (in public) to my knowledge, other than the interviews he did with his long-time friend Eckhard Schimpf for his book ("Einer dieser verwegenen Kerle") which is also a good source on his involvement in 917 development. At any rate, I find it hard to believe that the often-quoted fly-pattern actually tells so much useful information, at least not in the way it is most usually mentioned about the 917 (lots of flies in the front, no flies in the rear, ergo bad airflow on the rear) - I'd expect that the rear on any car, even several ones with very much working rear aerodynamics will be comparatively clean of flies and other debris as the impact of those particles will mostly happen around high-pressure spots such as the frontal area, not an area of laminar flow as you'd want along even an effective downforce-producing body section at the rear. With the early 917 tails that they ran, the only part where I'd expect any splatter would be the vertical stabilizer, perhaps that's what they meant. I'd hazard the guess that the decision to let this be claimed by the brits was also influenced by that fact that at Porsche there were several big heads (which may have included Piech himself) who held the "streamlining" concept in the highest regard - as is logical for a company used to bringing small-engine cars to Le Mans, one of the fastest races there was; their natural instinct in terms of aerodynamics would be to run as clean as humanly possible. I'm sure there was some hesitation to "ruin" the car in that regard with that rear spoiler section, which held back the performance initially - and even if the problem was known to several people including Ahrens, the situation may have required an external actor to pass..

@@decnet100 interesting comment. Food for thought. Thanks for replying. I drive the 917k in a simulator on the nordschleife in Virtual reality. It’s my fav race car besides 908/956/962. it’s not the real thing and it’s already so bonkers to hold the car on the track, makes you appreciate how hard it really must have been.

John Wyer's team....specifically led by John Horsman during Fall 1969 testing in Austria..... solved the aero issues.

Ah the Germans annoyingly good at almost everything when it comes to making cars and virtually every other aspect of engineering they reign supreme

Martini for me

they are good, aye.

Those are awesome on the right car the 555 and sometimes Marlboro too if it fits hIsToRiCaLlY

@@Moto_Medics Ooooh. I forgot all about Marlboro. Good pick.

John Player special is another good one

917/30 can-an Was able up to 1200hprs at max Turbo setup and weight around 800 kg.. OoF

There are "some" (toooooo many) other Facts he did wrong. Mostly everything about the 1st longtails and that K just means kurzheck / shorttail and so on.

"Porsche 917 - Wikipedia" en.m.wikipedia.org/wiki/Porsche_917. In the 1973 Can-Am series, the turbocharged version Porsche 917/30 developed 1,100 bhp (820 kW).

917/10 TC 1000 PS 917/30 Spyder 1100 PS (Racetrim) 917/30 Spyder 1570 PS (Fullboost 2.24 bar)

Where did ya present it bro

They eventually had to use a wind tunnel for 1971.

Mein got muss da sein

@@joshgee8714 so ein Bockmist aber auch.

@@joshgee8714 Mein Gott, muss das sein?

@@dj1rst exactly

Get ready for Germans without sense of humor

*shows picture of concorde, which was aluminium* .. talks about Ti. Mhmm.

@@craigykart Still had Titanium components, just like he said.

Same here

I'd thought the same, and even if that wasn't used in this I wonder if that could be used? In a lot of structures rigidity and strength in compression is a much bigger challenge than in tension. I could imagine a large thin structure pressurized with gas (possibly even helium - wouldn't float but a large structure at high pressure it could possibly save a few kilos, and in a case like this every gram counts) with the result that the material itself - probably ultra-thin carbon fiber - only has to be strong and stiff in tension. Sort of like a high-strength high-pressure balloon, we can think of balloons and other inflatable things as ultra-lightweight things with no stiffness whatsoever until inflated, this would have some but far less, becoming much stronger and stiffer when inflated. Only issue I could see is safety and reliability, the safety rules might not like it. Basically if a big hole rips in the car, it suddenly looses all it's strength and stiffness, leaving the driver surrounded by little more than floppy bedsheets at 200 mph.

The nitrogen solution comes from aviation, it was nothing new. Airplanes main spar are filled with pressurized N2 for the same reason.

Me!

Great video, as always. I do have to get used to your Imperial System. Could you at least put the speeds in km/h as text on screen if you do not want to mention them please?

Absolutely! For the tube to collapse it must reduce its internal volume. Look at all the American rockets and missiles of the 1950-'60's that couldn't support themselves, but had to be supported with their fuel/oxidizer and helium ullage. Edit: pressurizing the tube(s) puts the whole structure in tension, though gases being compressible will allow some 'spring'

@@jimurrata6785 Yeah great stories, and I really liked to ponder on the fact that the frame would be compressible (gas pressure+alu frame) as you describe;-) Do you think they utilized it as we imagine, or as crack/fail detection only?

@@bellybutthole I think any time a RACE TEAM releases a reason for engineering some component a certain way they have other advantages they're not talking about. I wasn't a fly on the wall, and understand how pressurization would allow for crack detection, but Porsche had some of the best engineers and metallurgists in the world then. They were not ignorant of the effect the pressurized nitrogen would have on chassis stiffness (and, of course it adds no weight!)

@@jimurrata6785 Well the peassure-leakage-crack logic is very sound yes. And I think you are right.

Don't know about the Porsche but the Concorde is G-BSST, one of the prototypes, and it's at the Fleet Air Arm museum in Yeovilton, England. In that photo shoot it's pretending to be G-BOAF, the last to be built and the last to fly. It's fascinating to look around especially with some of the test equipment still on board. There are videos of it on KZfaq :)

Actually, Ford withdrew from the series when the FIA reduced engine displacement to three liters for prototype cars (Group 6) and five liters for "production sports cars which had at least 50 chassis made (Group 5). The Ford GT-40 MKII and GT-40 MKIV that won Le Mans in 1966 and 1967, respectively had 7 liter engines. Ford's entire racing program was rendered obsolete by the stroke of a pen. Ferrari’s 4 liter 330P4 was also made redundant by the new rules. Group 5 was intended to consist of Lola T-70s and Ford GT-40s with 5 liter engines. Group 6 would consist of the Alfa Romeo T33/3, Ferrari 312P, Matra 650 and Porsche 908 which all had 3 litre engines. The FIA did not anticipate that Porsche would produce 50 5 litre 917s... There are impressive photos of the cars lined up for the FIA to review. BTW, John Weyer's Gulf team beat at Le Mans Porsche in 1968 and 1969 using Ford GT-40 chassis 1075. Porsche hired him to run their team for the 1970 season. It was actually John Horseman on Weyer's team that determined the issue with the rear deck of the 917 after observing Jo Siffert driving the 917 PA intended for the 1969 Can-Am series. The PA was an open cockpit car and didn't have the long, tear drop shaped tail of the normal 917. The Gulf team mocked up a new tail and it worked very well. Thus was born the 917K.

@@JanZizkaMetal Ah, I see. Thanks for the info! I’m not great when it comes to this Classic Le Mans stuff lol

@@mdewulf0922 Here's something you might find interesting. kzfaq.info/get/bejne/oJ-Idqh-mbmWqY0.html

theres a difference between flat v and boxer

@@mathias6369 Yes, but the 917's engine wasn't a boxer.

I lost brain cells reading all 3 of these comments

@@ProVision3187oh yeah? i just repeated the sentence that was written in the video and corrected it. other guy said there are differences between 180 deg v engines and boxers which is true , and the second guy said 917ks engine wasnt a boxer which is also true. so what the fuck are you even talking about

It's a Flat 12, not a Boxer 12. 180 degrees is not a V, it's a flat line.

"Porsche 917 - Wikipedia" en.m.wikipedia.org/wiki/Porsche_917. In the 1973 Can-Am series, the turbocharged version Porsche 917/30 developed 1,100 bhp (820 kW).

@@sandybarnes887 Yes, but in this video he is referring to the 917k that competed at Le Mans, and they only ever produced around 600.

@@AndyCharlesMusic You can talk about the engine separate from the chassis.

@@sandybarnes887 ...totally different car. No endurance-racing-trim 917 ...the closed coupe cars.... EVER had 1000 HP. Started with 520 in 1969 and ended up even after 2 size changes ( from 4.5 liters....to 4.9....then to 5.0)....never got over 560, maybe 600 HP. The turbo cars are also over-rated by urban legend...yes, on a dyno maybe hit 1500 momentarily, but ran races under 1000 HP.

for real he is too good for us lol

@Right Above You Helium and Hyrdogen have the bad property of leaking even when there are no cracks. Could've been part of the consideration.

Like the other guy said. Helium has a tendency to leak through things even without a crack so wouldn’t be ideal. Also nitrogen would be much cheaper and easier to get. And the difference in a helium filled chassis and a nitrogen filled one would probably only be a pound or two. You could save that weight easier by sending the driver to the bathroom.

Urban legend...no 917 ever hit 400 km/H ( 250 mph). www.mulsannescorner.com/maxspeed.html

@@TheWilferch It could, do... It would have needed more than Talladega: www.roadandtrack.com/motorsports/a29517421/mark-donohue-porsche-917-talladega-record/

@@therrydicule ...I know that effort...and look....even that car with 1200 hp...did what?.... a 220-225 mph?,....maybe hitting 240 on the straight?. The car had a CanAm body, where downforce was necessary, and the car had an enormous frontal area....it was wide with large Cd or drag coefficient. Here's a factoid for you and others to chew on.....the needed HP to get to a certain speed, increases with the CUBE of speed. Yes....raised to the "third power". If this means nothing to you from a math standpoint....let me use an example. A good 911 can hit 150 mph with 200 HP. To go just 50 mph faster, ...to hit 200 mph....it will need about 470 hp. Think this thru....we can't say "coulda-woulda"...the fact is ....it didn't.

@@TheWilferch Dr Helmut Marko and some other old dutch guy raced le Mans in the past as collegues ( he told on tv recently while having dr Helmut Marko on a live feed.) and they said, they did reach 400km/h back in the 70ties'. the 917 turbo had over way 1000 HP

@@TheWilferch i guess you can apply for a job. careers.mercedesamgf1.com/vacancies/ www.redbull.com/int-en/redbullracing/jobs

I mean, when a crash is severe enough to break the chassis there wouldn't be much left of the driver either, as they sat so far in front that their feet were in ahead of the front axle. And there wasn't a crumple zone. If I remember correctly it was Richard Atwood who said that a slight shunt into the pit wall would've been enough to break both of your legs.

@@mikeblatzheim2797 true but if a line were to blow it could be really bad

This video did a poor job of delineating the model that had the very bad aerodynamics. It was the very first version of the 917. To race the car Porsche had to produce 25 cars for homogenization. One privateer said the car scared him to death. He died on the very first lap. Note: that was the very first version of the 917.

That was a 908 and he didn't Win, he and Peter Revson came in Second....sheesh

@@Timinator62 I heard the officials were bought out by Ferrari..... Andretti was second.... It was there first prototype win in years so they made sure of it....

@@MiguelGarcia-vj7oo LOL Ok dude whatever