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Formula 1 RPM's 3

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butelja

butelja

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I just caught part of a F1 race on cable over the weekend. I was astonished by the incar camera with telemetry showing the tachometer. The engine was wound out to 18K+ RPM before every shift, and even on the "slow" portions of the course, the tach never seemed to drop below 12K RPM.

How on earth do these engines hold together? I imagine they have very short stroke, but what about the valvetrain?
 
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As Roger Penske once said - "all it takes is cubic money." With enough R&D, you can develop lightweight valves, very gentle camshaft profiles and matching springs so it all works. Obviously, these engines are all multiple valve, which cuts the weight right there and through shear valve head area, may allow a lower total lift, also aiding the extreme RPM.

Blacksmith
 
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It is a lot more complicated than just enhancing the 'basics'. F-1 engines cost in the neighborhood of TEN MILLION DOLLARS these days. They have, obviously, the BEST of engineering including pneumatic valve springs, VVT, and the cutting edge in ECM(as well as electronic chassis and fuel management) technology. The Ferrari typicaly runs 18,500 rpm and, if you watched, at the end of the Canadian Grand Prix, M.S. backed off(???) to a more 'reasonable' 17,500 rpm! I sure would like to see a dyno sheet on one of these F-1 engines.

Technology does change the face of racing---production based NASCAR engines @ 360 cu.in.+/- and 9000/10,000 rpm (!)---the little vintage Sprite/Mini engine that I was 'thrilled' to get7,500rpm out of in 1967 is now regularly turning 9,500 rpm . Some of my racing engines of the 60's that I was on the cutting edge with at 8,500 are now turning 10,500 to 11,000 rpm IN VINTAGE RACING!!!
Like you said, "all it takes is cubic money."


Rod
 
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Why turn those engines up so high ???? :)

Answer_1 = ( Torque x RPM ) / 5252


Answer_2 = ( Answer_1 /CID )


....just thought i'd stir up things ?

HP/CID Ratio is RPM dependent





Larry Meaux (meauxracing@mindspring.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers
Support Israel - Genesis 12:3
 
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There is the answer to the HP vs torque question. These engines produce 1/2 the torque of a an engine with the same HP and can only rev to 9,000rpm. and only 30% of the torque that a 6000rpm rever will produce.

Hp wins races, torque is as meaningless as RPM when it is alone as a factor. contrary to the public saying!!

Mark
 
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I brought up the same point in a couple different 'discussions' around the 'net over which is more important. I haven't been able to get anyone to say &quot;Yes, my 300ft-lb low-revving motor will beat an F1 car any day&quot; and they will still tell me that torque is more important. <sigh>


-=Whittey=-
 
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in the (DragRacing Section) in the MotorSports Forum on America Online , back around the time when the Chrysler ProStock Team had the BreakIn , and were dominating NHRA ProStocks ..... i had some inside info from a certain guy
that they were making their Peak HP numbers between
8000 -to- 8200 RPMs .....at the same time Warren Johnson was claiming his engines were making their Peak HP
at 8700 RPMs .

Anyways this same guy who gave me this inside Info was very impressed with the Chrysler ProStock Team , and reasoned they really knew what they were doing , more than anyone else !

When the news came out about them using Nitous ,
i ran computer simulations on Foot-Distance increment times
down 1/4 mile on the Chrysler car , couldn't really tell from simulation that they were pushing or applying Nitrous button at any one point , it didn't showup in Foot-Increments ...so i reasoned they might be applying Nitrous
from the Start or some where very early a feet feet from starting line and keeping it applied down 1/4 mile
..but still no real proof ....till this same guy reveals their power/torque curves to me , i run the 1/4 mile simulation and it doesn't correlate !!

From my simulation the Chrysler ProStock team back then would have needed almost 860 Lbs of Peak Torque
and somewhere around 830 average lbs of Torque over the
RPM band to run the numbers

In R & D in Prostock State of Art engine building , you might be able to pickup 60 HorsePower over your competitor , but its going to be very hard to have 60+ lbs of Torque over your competitor or find a 60 Lbs Torque advantage .

860 Torq / 500 CID =1.72 Ratio

Today , the State of Art ProStock Technology
a 500 CID engine with 16 to 17:1 CR might be very lucky to
get 1.64 TQ/CID Ratio = 820 Lbs @ 600 RPM/SEC Accel rate

and now days , teams are making Peak HP from 8900 to 9200
or so ..... since with a given size CID engine (NA)
the most you could probably make is somewhere around 1.6
to 1.64 TQ/CID Ratio ...so to go faster you find a way to move the peak HP point higher so you get more HP/CID Ratio
and go faster

you see this same exact trend in all forms of MotorSports
this trend will usually dominate

since the amount of peak torque is pretty much locked in , you have to find a way to move this torque curve higher producing more HP/CID Ratio

Larry Meaux (meauxracing@mindspring.com)
Meaux Racing Heads - MaxRace Software
ET_Analyst for DragRacers
Support Israel - Genesis 12:3
 
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One of the torque vs horsepower threads involved towing. No way is a low revving torque monster going to beat a F1 car on the racetrack. But put a 10,000 pound trailer behind each and see which you like better. According to all the numbers, the F1 car should tow it just fine, but you'll get tired of all the shifting needed to stay in the power band every time you encounter an upgrade. The torque monster might drop back one gear for the big hills. Its all application. You want to tow carefree, go for torque, you want to be the absolute fastest, go for the horsepower, but be prepared for a narrow power band and lots of shifting.

Blacksmith
 
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Bah, only you old guys hate shifting :) :) :)


-=Whittey=-
 
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Good discussion, but it seems to have strayed. Back to the original topic. Can anyone enlighten me as to the specifics of how the &quot;pneumatic valve springs&quot; in the F1 engines work? Are they used in combination with a desmodronic (2 cam lobes, 1 to open 1 to close valve) valvetrain, or is it more of a conventional DOHC setup?
 
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butelja,

In actuality, F1 engines use pneumatic valve closure systems to replace valve springs. The system works by having a very small pneumatic chamber above each valve. The chamber use high pressure air to close the valve after the camshaft lobe has moved beyond its peak. There is no desmodromic actuation. The reason this translates into higher engine speeds is because metallic helical springs were at their limit to maintain control of valve motion at high speeds. Now, valve motion is not the limiting factor of engines -rather, it is combustion time and crankshaft resonances, according to the rumor mills.

For more information, try the following F1 sites:

(go to the technical forum)
 
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The rumor mill has it that a 'major engine mfgr' has an engine turning 22,500 rpm on the dyno. Something to think about---reliability ????---power ????
If you read between the lines of my previous post you may get the idea that I know where all this is going but, you would be WRONG! Man, I sure would LIKE to know, though!


Rod
 
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R/C Car motors can turb 32,000rpm, but thats glowplug and nitromethane. No boost though. 0.21cid pushing 2.5hp is pretty impressive. In the assy view I don't see any valves though, so i'm thinkin its 2-stroke.


-=Whittey=-
 
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If you do not subscribe to Racecar Engineering or RaceTech magazines, I would recommend checking them out. They offer the most in-depth look at racing technology. I can't remember which issue, but one of the past Racecar Engineering issues had an excellent article on F1 pneumatic valve trains, even featuring some line drawings from Tony Matthews (good technical illustrator).

The first two links below are for the general magazines, and the last one is a web version of an article on the Jaguar F1 engine from 2000.



 
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Finally a few thinking person's magazines about fast cars. It sure seems like most car mags are stuck in the 60's and 70's, focuses on massive cubic inches and going in a straight line. Nothing wrong with that if its your bag of tea, but I have a lot more respect for vehicles that can do it all from a performance standpoint.
 
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gunnarhole,

Excellent Link!. I follow F1, but not that closely - I was amazed at the things they do/have done/will do.
[surprise]
Blacksmith
 
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WOW!!! The only 4-stroke I've ever heard of spinning that fast (22,500 rpm) was a Honda CBR250 motorcycle. To think of a F1 car engine doing it is pretty amazing!

>Evelrod:The rumor mill has it that a 'major engine mfgr' >has an engine turning 22,500 rpm on the dyno. Something >to think about---reliability ????---power ????
 
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Nobody has mentioned fuel efficiency yet.

Surely when you go to those high revs, effeciency 'drops through the floor'. It seems the only reason they do this is the limit on the 3 litre capacity.


... well worth the visit

Speedy
 
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