67 replies to this topic

[ray b]

what is the power/torque curve of a modern F-1 motor??
where is peak torque and how wide is the useable torque curve
surely the old bit about hp crossing torque at 5xxx is out in a 18,000 rpm motor


btw why does torque drop at hi rpm's as hp goes up near red line
and drop as you hop up a street car motor to breath better and rev higher
ie bigger valves or porting and headers without a hi lift cam

[Ray Bell]

The torque figure might actually go up too...

But the main thing is that revs increases the power because it introduces the amount of work that can be done... torque only measures the effort that can be applied.

[xflow7]

I take it you are referring to HP=T*RPM/5250? That actually does still apply as it comes directly from the definition of horsepower.

Don't really know what the power curve of an F1 motor looks like. I'm sure they're quite peaky, but you can get a minimum value for peak torque.

Figure 840HP @ 19000 rpm. That gives 232 ft-lbs of torque @ 19000 rpm.

I don't have any idea what peak torque might be, maybe 250-300 ft-lbs? I pulled that out of my butt, though. Maybe someone on here has better information.

There are alot of reasons why torque drops at higher rpm's. Internal engine fricition is a big one. As well, depending on how the manifolds, etc are tuned, peak volumetric efficiency may be at less than maximum rev's (in order to "fatten" the torque curve lower down and improve driveability).

The reason power generally keeps going up well after torque is dropping off is due to the fact that fundamentally, power=torque*speed (that's where the relationship above comes from with a unit conversion). So even if the torque is dropping off somewhat, power can increase as a result of the rev increase.

As motors are tuned for hi-rpm performance the torque peak would get pushed higher in the rev band and torque low down tends to be reduced. I believe, much of this is because by porting, going to large valves, TB's etc, you reduce the velocity of the incoming charge and lose some beneficial mixing/swirling effects at low engine speeds.

But you're always fighting the frictional and other losses with higher engine speed so you can end up compromising peak torque value in order to boost peak power by enabling higher revs.

Hope that helps. And I'm sure more knowledgeable people will be along shortly to add more (or correct me )

[Hellenic tifosi]

I remember that quite some time ago, someone gave us some numbers for Ferrari's 049 engine, so I used GNUPLOT to make a graph:

[McGuire]

Originally posted by ray b
surely the old bit about hp crossing torque at 5xxx is out in a 18,000 rpm motor

btw why does torque drop at hi rpm's as hp goes up near red line

Peak torque always arrives at the rpm of peak MEP (mean effective cylinder pressure). At that speed, the engine is also at/near peak SFC (specific fuel consumption -- unit of fuel consumed per unit of power produced). At that point, air is filling the cylinders at maximum efficiency, and the fuel is being burned at maximum efficiency as well. That produces maximum pressure in the cylinder, which produces maximum torque on the crankshaft.

Above that rpm, the engine may be able to make more torque per minute (by spinning the crankshaft faster, thus producing more power strokes per minute) but it cannot make more torque per power stroke. Above the rpm of peak torque, the engine is making less torque per revolution (he said redundantly).

MEP x displacement/ 48 pi = Torque

Torque x RPM /5252 = Horsepower

conversely

Torque = 5252 x HP/RPM

For all 4-stroke piston engines horsepower and torque are identical at 5252 rpm, no matter what.

Above the engine's rpm of peak torque, all its efficiencies are falling off, by definition. Less air is getting into the cylinders per intake stroke, mainly due to the increased friction of the air molecules in the intake tract. Meanwhile, the engine's mechanical losses per revolution are climbing, due to inertia (as to the square of the speed) and friction (cube of the speed). The engine can make more power by turning faster, but the amount of torque it makes per revolution is falling. At some point the amount of torque produced *per minute* (i.e., horsepower) reaches the limit imposed by the losses. That point is the rpm of peak horsepower.

[Chevy II Nova]

Originally posted by ray b
btw why does torque drop at hi rpm's as hp goes up near red line
and drop as you hop up a street car motor to breath better and rev higher
ie bigger valves or porting and headers without a hi lift cam

Usually a street motor loses torque in favor of top end power. Remembering that torque is power taking into account revs, this is a logical deduction.

[turby]

@McGuire

For all 4-stroke piston engines horsepower and torque are identical at 5252 rpm, no matter what.

I think I know what you intend to say, but this is physical nonsense. 20 years ago my physics teacher would got a heart attack. Its the same if I would postulate:

For all free falling bodies in the earth's gravitational field, velocitiy and acceleration are identical after 1 second.

You cannot put power and torque in the same soucepan. You cannot compare apples and pears even both are fruits. Of course the numerical values could be identical but there are still units.

Just 20 milli-$ from me

Uli

[alexbiker]

I think I know what you intend to say, but this is physical nonsense. 20 years ago my physics teacher would got a heart attack.:

Er, your physics teacher would have a had a very large number of heart attacks - can I contact him as an outlier in myocardial infarct survival figures?

Look again at the formula - Horsepower is a function of torque and rpm, and a constant to correct to the arbitrary units - 5252. So therefore, all engines at 5252 rpm have the same HP as torque in lb ft. By definition - HP = (torque x rpm) /5252, so at 5252 rpm, HP = (torque x 5252)/5252 = (torque x 1)/1 = torque.

Power and torque are related directly as reflections of each other, torque being an expression of energy and HP and expression of power as energy per unit time, so adding revolutions per minute makes torque and expression of power.

Alex

[blkirk]

Yes, that is true, but only when power is in units of horsepower and torque is in units of ft-lbs. If you switch to kW and N-m, I think you'll find that the 5252 conversion factor has changed.

[Greg Locock]

and just in case anyone was wondering, 5252 is not a 'magic' number, it is 33000 lb ft/min (the definition of a horsepower) divided by 2*pi, the conversion figure from linear to rotary motion.

[desmo]

Actually this being an F1 forum, given the sports rather Anglocentric nature and the the "old school" nature of most of the engineers involved, I think you'd find most F1 engineers rather surprisingly perhaps still working in ft-lbs and horsepower units!

[McGuire]

Originally posted by turby
@McGuire



I think I know what you intend to say, but this is physical nonsense. 20 years ago my physics teacher would got a heart attack. Its the same if I would postulate:

For all free falling bodies in the earth's gravitational field, velocitiy and acceleration are identical after 1 second.

You cannot put power and torque in the same soucepan. You cannot compare apples and pears even both are fruits. Of course the numerical values could be identical but there are still units.

Just 20 milli-$ from me

Uli

Not at all. Torque is our expression for rotational work -- in this case, two revolutions of an IC engine's crankshaft (one operating cycle). Horsepower is simply torque over time, in this case one minute.

HP = RPM x Torque/5252

Torque = 5252 x HP/RPM

Horsepower and torque will be of identical numerical value at 5252 RPM. That is not a rule of thumb. That is The Law: One hp = 33,000 ft/lb/min. There is nothing mystical about 5252 rpm. It's just shorthand for 33,000/2pi.

Perhaps you are just saying that hp and torque are not "the same thing." If so, you are correct. However, torque and hp certainly are from "the same saucepan." Indeed, they are essentially two ways of quantifying exactly the same thing -- the pressure produced in an engine's cylinders, as translated into useful work at the crankshaft flange. Torque refers to the amount of work performed per operating cycle; horsepower to the amount of work (torque) performed per minute. Obviously, my post drew a number of clear distinctions between torque and horsepower. I believe one could say that was the point.

[McGuire]

Originally posted by blkirk
Yes, that is true, but only when power is in units of horsepower and torque is in units of ft-lbs. If you switch to kW and N-m, I think you'll find that the 5252 conversion factor has changed.

Sure. One hp = 33,000 ft/lb/min. 5252 = 33,000/2pi (approx). If you prefer to work in the Continental manner, one newton-meter is the *rotational equivalent* of one joule, while one KW is 1000 joule-seconds. Same concepts, different units. In either system, power is simply torque over time.


One Kilowatt = .746 SAE horsepower

One Newton-Meter = 1.356 lb-ft.

These are just factors for converting all the various newtons, seconds, and watts into feet, pounds, and minutes. All this horsing around with different standards carries some irony, because James Watt invented and defined the "horsepower" in the same form it has today, but the "watt" is named after him.

[mp4]

I read a blurb in "Car and Driver" when they were allowed to test a Jag F1.
They figured the car had about 750 b.h.p. at roughly 13500 revs with a torque measurement of 260 pounds-foot at the same revs.
The boys at Jag didn't comment on any of this.
I trust this is some sort of measure.

Cheers

[McGuire]

Originally posted by mp4
I read a blurb in "Car and Driver" when they were allowed to test a Jag F1.
They figured the car had about 750 b.h.p. at roughly 13500 revs with a torque measurement of 260 pounds-foot at the same revs.
The boys at Jag didn't comment on any of this.
I trust this is some sort of measure.

Cheers

If an engine produces 750 hp at 13500 rpm, this we know for sure: it produces 291 lb ft of torque *at that rpm.* Meanwhile, if an engine produces 260 lb ft of torque at 13,500 rpm, it is producing 668 hp.

HP = RPM x Torque/5252

Torque = 5252 x HP/RPM

These formulas -- and the fact that hp and torque are always identical values at 5252 rpm -- can be very useful tools. For example, we are often handed just two bits of data about an engine: its peak torque @ rpm; and peak hp @ rpm. These alone don't seem to give us much of a picture of what the engine is like.

But using the formulas above, from those numbers we can calculate hp at the rpm of peak torque, and torque at peak hp rpm. And we know that no matter what, torque and hp will be identical at 5252 rpm. So we have gone from two data points to five -- and from there we can construct a rough but useful simulated dyno chart of the engine's output characteristics.

[Paolo]

Originally posted by McGuire

So we have gone from two data points to five -- and from there we can construct a rough but useful simulated dyno chart of the engine's output characteristics.

Incidentally, exactly what I'm doing in this moment at the office, using a set of cubic splines.

[Dmitriy_Guller]

Hmm, I just don't understand how you can go from two independent data points to five, that seems to contradict statistics. Horsepower and torque are one-to-one functions of each other, therefore there is no benefit in finding one from the other for regression purposes, unless I'm missing something. For the same reason, I see no reason why I should be excited about two curves meeting at 5252 any more than about the fact that one would be twice as high as another at 10504 RPM, or three times as high at 15756 RPM. How would you know how high you should set the point at 5252 RPM anyway? Are there any other assumptions made about the engines that you use to make a ballpark torque curve?

[Greg Locock]

They aren't independent numbers, hence the apparent case of reverse entropy does not exist.

The torque vs rpm and power vs rpm curves contain identical information (in an absolute sense) so no information is created or destroyed when you transform one to the other.

[Dmitriy_Guller]

Originally posted by Greg Locock
They aren't independent numbers, hence the apparent case of reverse entropy does not exist.

The torque vs rpm and power vs rpm curves contain identical information (in an absolute sense) so no information is created or destroyed when you transform one to the other.

Exactly, that's what I'm saying, so I'm wondering how you go about creating a ballpark torque curve with only two independent data points.

[Dmitriy_Guller]

Oh, it just dawned on me, you know that the slope of the tangent line of torque curve at torque peak is zero, and the slope of the tangent line of horsepower curve at HP peak is also zero, and from that you can derive the slope of the tangent line of torque curve at HP peak RPM. That gives you four data points, enough for a cubic polynomial. I don't see how 5252 thing comes into the picture, though.

[Greg Locock]

Wow, that was subtle, good thinking, although of course the power peak in particular might be at the red line, so may not have a zero gradient.

[Dmitriy_Guller]

Does that happen a lot, that power peak is at the red line? If your power peak is defined by rev limit, I would guess that tuning the engine to shift torque curve (and consequently power curve) to the left would be a logical thing to do. BTW, does anyone have any figures and real dyno data for some car, I want to see how well this predicts the actual torque curve.

[desmo]

Overrun past power peak in an F1 engine will be minimal, figure 500-1000 rpm.

[wegmann]

Originally posted by desmo
Overrun past power peak in an F1 engine will be minimal, figure 500-1000 rpm.

I think that you'll find in the technical regulations (at least it was there a couple years ago) that the rev limiter must be set "significantly" past the power peak. I'll go look for the actual rule ...

OK, found it in the 2001 Technical Regulations. Rule 5.10 says, "Engine rev limiters : With the exception of the car speed limiter below and subject to Article 8.3, engine rev limits may vary for differing conditions provided all are significantly above the peak of the engine power curve."

I looked in the 2003 regulations and it is gone - probably had something to do with TC.

[McGuire]

Originally posted by Dmitriy_Guller
Hmm, I just don't understand how you can go from two independent data points to five, that seems to contradict statistics. Horsepower and torque are one-to-one functions of each other, therefore there is no benefit in finding one from the other for regression purposes, unless I'm missing something. For the same reason, I see no reason why I should be excited about two curves meeting at 5252 any more than about the fact that one would be twice as high as another at 10504 RPM, or three times as high at 15756 RPM. How would you know how high you should set the point at 5252 RPM anyway? Are there any other assumptions made about the engines that you use to make a ballpark torque curve?

There is a direct mathematical relationship between hp and torque, and between hp and rpm. However, there is no such relationship between torque and rpm. Thus hp and torque may trend in opposite directions relative to rpm, and often do above the rpm of peak torque. That is precisely why graphical depictions of horsepower and torque relative to rpm -- the time-honored output graphs and dyno charts we have seen for decades -- are a valuable tool in studying an engine's operating characteristics.

[Yelnats]

I've alwasy taken the old saw about high performance engines lacking tourque with a grain of salt. The tourque generated by a well designed engine is usually related in a positive manner to it's peak HP, ie the higher the HP per unit displacement, the higher the touque. Of course I'm not talking about back yard souped up engines which may have lacked engineering resources, rather properly engineered race or street engines.

This misconception probably stemed from experiences when comparing two engines of the same peak power, one of smaller displacement but high reving. Usually the higher reving engine (in recent decades) developed ever bit as much tourque per unit displacemnt (or more!) but required higher revs to get into it's POWER band, a different thing entirely.

Looking at the tourqe curves shown above, I doubt if a diesel would develop as much tourque per unit displacement and indeed the modern F1 engine is could be the touqueiest (naturally aspirated, per unit displacement) engine ever made. I await comment from the hard working math researchers that we rely so heavily on in this forum to keep us straight!

[McGuire]

Originally posted by Yelnats
I've alwasy taken the old saw about high performance engines lacking tourque with a grain of salt. The tourque generated by a well designed engine is usually related in a positive manner to it's peak HP, ie the higher the HP per unit displacement, the higher the touque. Of course I'm not talking about back yard souped up engines which may have lacked engineering resources, rather properly engineered race or street engines.

This misconception probably stemed from experiences when comparing two engines of the same peak power, one of smaller displacement but high reving. Usually the higher reving engine (in recent decades) developed ever bit as much tourque per unit displacemnt (or more!) but required higher revs to get into it's POWER band, a different thing entirely.

Looking at the tourqe curves shown above, I doubt if a diesel would develop as much tourque per unit displacement and indeed the modern F1 engine is could be the touqueiest (naturally aspirated, per unit displacement) engine ever made. I await comment from the hard working math researchers that we rely so heavily on in this forum to keep us straight!

The F1 engine's 350 lb ft of torque -- 116 per liter -- is indeed impressive. But then, it should be impressive. These are ostensibly the most highly developed engines in the world, and the pursuit of horsepower is essentially the pursuit of torque.

An NHRA Pro Stock engine will produce displacement-specific torque close to that range, which is pretty impressive considering it is limited to eight enormous cylinders, two valves, pushrods, and carburetors.

The IRL engine is also restricted to eight cylinders, and to a maximum bore of 94mm (which limits valve area) But it is still a good match for an F1 engine in displacement-specific torque output. The artificial rev limit imposed by the series has forced development series toward finding more MEP (and therefore torque) and decreasing operating losses. Of course, F1 involves far greater resources, but does not focus so much on MEP and mechanical efficiency... more on achieving ever higher rpm.

Now I will grant you this engine is a sort of freak, but Vance & Hines has developed a (loosely) Harley-Davidson based V-twin for the NHRA Pro Stock Motorcycle category which reportedly produces 360 lb ft of torque with 160 CID (2.62 liters). That's more total torque than in an F1 engine of greater displacement, and it does it with only two cylinders.

Meanwhile the Caterpillar C12, your run-of-the-mill 732 CID, six-cylinder turbo-diesel truck engine, develops 1650 lb ft of torque at 1200 rpm. That's 137 lb ft per liter, in a mass-produced truck engine employing no exotic materials or processes, and with a service life of something over one million miles. These engines will also deliver 8 mpg (somewhat better than an F1 car, eh) while pulling over 40 tons down the road. This is not the latest or most powerful truck engine Cat builds either, and they also produce some marine variants of their engines with higher yet specific outputs. I have no idea how much torque one of these units could produce in full-race development comparable to an F1 program -- it's almost too scary to contemplate.

[McGuire]

Originally posted by Yelnats
I've alwasy taken the old saw about high performance engines lacking tourque with a grain of salt. The tourque generated by a well designed engine is usually related in a positive manner to it's peak HP, ie the higher the HP per unit displacement, the higher the touque. Of course I'm not talking about back yard souped up engines which may have lacked engineering resources, rather properly engineered race or street engines.

This misconception probably stemed from experiences when comparing two engines of the same peak power, one of smaller displacement but high reving. Usually the higher reving engine (in recent decades) developed ever bit as much tourque per unit displacemnt (or more!) but required higher revs to get into it's POWER band, a different thing entirely.

Depends how you look at it.

Engine A produces 150 hp at 4,000 rpm.

Engine B produces 150 hp at 8,000 rpm.

That means we know engine B produces only half as much torque as engine A. By definition: Torque = HP x 5252/RPM. Engine A produces 197 lb ft of torque, while Engine B produces only 98.

If you put Engine B in a sedan, it will not only require taller gearing than Engine A, it will require roughly twice as many gears in the box to produce the same acceleration. Why? With only half the torque, the rpm drop between gears will be twice as large.

[foolio]

Originally posted by McGuire


Depends how you look at it.

Engine A produces 150 hp at 4,000 rpm.

Engine B produces 150 hp at 8,000 rpm.

That means we know engine B produces only half as much torque as engine A. By definition: Torque = HP x 5252/RPM. Engine A produces 197 lb ft of torque, while Engine B produces only 98.

If you put Engine B in a sedan, it will not only require taller gearing than Engine A, it will require roughly twice as many gears in the box to produce the same acceleration. Why? With only half the torque, the rpm drop between gears will be twice as large.

Uh... this is the second time I've seen McGuire post this argument. Why hasn't anyone proved him wrong?

Assumption: A & B produce a flat torque curve.

Claim: Engines A & B perform exactly the same.

Proof:
We take the engine, put it in a box (black, of course) with only the output shaft pokin' out. Assuming you are deaf, can you tell which engine is inside the box?

No. I can make the blackbox engine's output characterics perform like A, by using engine B and putting a reduction gear of 2 at the output shaft. Similarly I can make the blackbox perform like B by using an overdrive gear of 0.5 on engine A. qed.

You do not need double the amount of gears for engine B. Engine torque is irrelevant. What is useful is how the peak torque number hints at the location of the power band.

[Dmitriy_Guller]

Originally posted by foolio


Uh... this is the second time I've seen McGuire post this argument. Why hasn't anyone proved him wrong?

I believe you're looking for "Shifting strategy" thread.

[red300zx99]

Originally posted by foolio
Engine torque is irrelevant.

nice name by the way

[Greg Locock]

"If you put Engine B in a sedan, it will not only require taller gearing than Engine A, it will require roughly twice as many gears in the box to produce the same acceleration. Why? With only half the torque, the rpm drop between gears will be twice as large. "

Let's put a 4:1 diff in B, and a 2:1 in A

Let's put a 3:1 first gear in B and 2:1 second gear

at 8000 rpm the wheel will be doing 8000/3/4 rpm = 666 rpm (developing 150 hp)

change into second gear, engine will be doing 2/3*8000= 5333 rpm, 100 hp

at 8000 rpm in second gear the wheels will rotate at 1000 rpm. 150 hp

Same sums for A, same gearbox

at 4000 rpm the wheel will be doing 4000/3/2=666 rpm (150 hp)
change into second gear engine will be doing 2/3*4000=2666 rpm, 100 hp
at 4000 rpm in second gear the wheels will rotate at 1000 rpm 150 hp.

Conclusions

Ignoring various (important, in practice) second order effects there is no difference in gearing requirements other than axle ratio for constant torque engines of equal rated power. The instantaneous power at the road will be identical at each speed. Therefore the performance will be identical.

[foolio]

Originally posted by red300zx99


nice name by the way

thanks. It tends to bait the real fools.

[ciaoduc1]

I used to be all confused on this whole torque/hp thing also until I read this:
http://vettenet.org/torquehp.html

The way I understand it, hp doesn't actually exist. There isn't a machine that measures hp. Dyno's measure torque and stick that number and the the rpm's where it occured into the famous formula and out spits the hp. HP is just a convenient way to say this engine or water wheel (or any other rotating thing) has "X" units of twisting force at "Y" revolutions per unit of time.

Look at the torque numbers for this guy: http://www.bath.ac.uk/~ccsshb/12cyl/ It over-revs at 103rpm! If it did rev to 5252 the torque and hp would be the same. 220 lb ft per liter...almost double an F1 engine. It would be a little difficult to make the aero work with this one though ;)

[alexbiker]

Originally posted by McGuire


The F1 engine's 350 lb ft of torque -- 116 per liter -- is indeed impressive. But then, it should be impressive. These are ostensibly the most highly developed engines in the world, and the pursuit of horsepower is essentially the pursuit of torque. . . . . [snip]

The pursuit of horsepower is not the pursuit of torque, unless we are talking in a rev-limited and displacement limited scenario. Essentially, the F1 teams are trying to maximise the area under the horsepower and torque curves, not peak torque or even peak horsepower. The only feasible way to do this with a normally aspirated engine is effectively to increase maximum revs, so peak torque may stay the same, whilst aforementioned area increases.

[McGuire]

Originally posted by foolio


Uh... this is the second time I've seen McGuire post this argument. Why hasn't anyone proved him wrong?

If that's what you want, I will simply hand you the point. It's an interesting subject with more than may meet the eye but we don't need two threads of niggling and gainsaying. If you think I'm totally full of crap that's perfectly fine with me too. I'm just here to offer my own $00.02 along with everyone else. It's all good.

[McGuire]

Originally posted by alexbiker


The pursuit of horsepower is not the pursuit of torque, unless we are talking in a rev-limited and displacement limited scenario. Essentially, the F1 teams are trying to maximise the area under the horsepower and torque curves, not peak torque or even peak horsepower. The only feasible way to do this with a normally aspirated engine is effectively to increase maximum revs, so peak torque may stay the same, whilst aforementioned area increases.

When you increase max revs, it's typically at the potential expense of the torque curve. (And the hp curve below that rpm, if you prefer to phrase it that way.) For example, greater port volume for high rpm will tend to kill airflow in the lower ranges. (Ve will track the torque curve.) So a central part of the exercise really is husbanding the torque curve. (Not peak torque.) With hp or torque, peak is just a number...on either side there are numbers (we hope) very close to it. Interesting though how the peak hp number carries so much mojo. The engine spends so little time there, especially in road racing.

[Engineguy]

Originally posted by alexbiker
The pursuit of horsepower is not the pursuit of torque, unless we are talking in a rev-limited and displacement limited scenario. Essentially, the F1 teams are trying to maximise the area under the horsepower and torque curves, not peak torque or even peak horsepower. The only feasible way to do this with a normally aspirated engine is effectively to increase maximum revs, so peak torque may stay the same, whilst aforementioned area increases.

Why do people make silly rigid blanket statements like this? An F1 engine developer will take power where he can get it. An improvement in MEP between 17,000 and 19,000 is just as desirable as finding a mechanical/materials solution to raise your redline from 19,000 to 19,300, which represents small gains, since it's at the gutless, rapidly falling end of the torque curve. Unless you can maintain a decent MEP in the newly obtained RPM range, the extra RPM is worthless. Do you actually believe that high-RPM MEP is as high as it will ever be? Historic reflection shows that such pronouncements are likely to look silly a few years later.

[alexbiker]

Er, that's a quote from the recent documentary following Renault's early season.

Their engine designer said it.

I respect his opinion.

Alex

[red300zx99]

Originally posted by alexbiker
increase maximum revs, so peak torque may stay the same, whilst aforementioned area increases.

mmmmm, more torque, yummy

[Barry Boor]

As a total ignoramous about these things, can someone explain to me how it is that today's immensely powerful F.1 engines can have, according to Jenson Button, NO TORQUE?

I just don't get it!

Simple words, please.

[TDIMeister]

Current F1 engines being naturally-aspirated, are limited in the torque output by the amount of air-fuel mixture they can trap and burn in one given cycle. This amount is finite because you can only stuff a certain amount of something in an enclosed volume at prevailing ambient conditions (there are other tricks one can employ like intake ram-effect and wave effects, but in the interest of the desired simplicity will not be discussed).

Wright's Ferrari F-2000 book had the maximum BMEP (brake mean effective pressure, which is basically an analog for displacement-specific torque expressed as an equivalent pressure) of the engine of that car at a little over 16 bar or 128 Nm/L. This is not even the highest BMEP achieved of all naturally-aspirated engines; some have exceeded 17 bar and some have even claimed over 18 bar. However, this maximum ceiling has been static for years and will likely continue to be for the foreseeable future.

F1 practice of ever increasing RPMs over the past decade is a function of rules that have forced naturally-aspirated engines of fixed displacement and no air restrictor. Restricting the intake air or fuel consumption, and simultaneously relaxing engine displacement, aspiration and engine layout rules would influence engine RPMs because higher RPMs mean higher frictional losses, and it becomes less profitable in an air- or fuel-restricted scheme to run very high RPMs.

[cheapracer]

Originally posted by Barry Boor
As a total ignoramous about these things, can someone explain to me how it is that today's immensely powerful F.1 engines can have, according to Jenson Button, NO TORQUE?

I just don't get it!

Simple words, please.

This is a 'feel' problem, not a lack of torque problem. Often refers to a peaky engine that must be kept on the "boil"/"cam"/"pipe", the torques there but quite high in the rpm range.

Lack of engine inertia/rotating mass is also a related 'feel' problem.

2 strokes have bared the brunt of this misnomer for many years for these reasons.

[dead_eye]

ray b- the old bit about torque crossing bhp at 5252 rpm wont go out the window if the engine revs at 2.9 billion rpm! bhp is a mathematical calculation the laws of physics have no effect on equations ;)

[Ninja2b]

Originally posted by desmo
Actually this being an F1 forum, given the sports rather Anglocentric nature and the the "old school" nature of most of the engineers involved, I think you'd find most F1 engineers rather surprisingly perhaps still working in ft-lbs and horsepower units!

In my experience, it's all PS and Nm these days, and has been for quite some time...

[McGuire]

Originally posted by Barry Boor
As a total ignoramous about these things, can someone explain to me how it is that today's immensely powerful F.1 engines can have, according to Jenson Button, NO TORQUE?

I just don't get it!

Simple words, please.

Well, to get right to the point they don't have much torque: just over 200 lb-ft. They make good power because they turn the hell out of them. Relative to Button's experience with V10s, the V8s have 20 percent less oomph where he can feel it.

It is a fact that the driver cannot feel horsepower, he can only feel torque... or to be perfectly accurate, thrust from the drive wheels. Just as your body can physically experience acceleration, but it cannot sense speed. Jenson is noting that compared to his previous engines, with these he must keep the revs right up, be mindful of his shifting, and that if the gearing is not just right on some corners, the car seems to lay there. That is what he is talking about.

[McGuire]

Originally posted by Ninja2b


In my experience, it's all PS and Nm these days, and has been for quite some time...

If there is a global standard it is kW and Nm but it doesn't matter, everyone can do the math.

EDIT: Along these lines we once had a bitter and protracted dispute here based on a confusion between the solidus and the virgule. I am not making this up.

[Barry Boor]

Thank you, McGuire, I think I'm getting the idea.

[Bill Sherwood]

Originally posted by McGuire



Well, to get right to the point they don't have much torque: just over 200 lb-ft.

Closer to 250 ft-lbs you'll find.

[McGuire]

If you say so, but that is not a tremendous amount either.

Personally, I would believe that number when I saw it SAE certified J1347. Until then I would apply the PR correction factor. This is F1 we are talking about.