Mclaren Lm

Some say top speed is 240.1 and some say faster...Anyone know for SURE?
:banghead:

The LM would not reach 240.1 mph due to the drag created by the rear wing and front spoiler which add additional downforce. My guess is that an LM would be good for roughly 220-225 mph maximum.

The standard road car did 240.1mph, but only with the 7500 RPM rev limiter removed. With the rev limiter in place the road car is probably good for about 230 mph.

>8^)
ER

The LM would not reach 240.1 mph due to the drag created by the rear wing and front spoiler which add additional downforce. My guess is that an LM would be good for roughly 220-225 mph maximum.

The standard road car did 240.1mph, but only with the 7500 RPM rev limiter removed. With the rev limiter in place the road car is probably good for about 230 mph.

>8^)
ER

Thats what i read - i also read that the LM would 'only' reach a max of 225mph, due to both the points raised by Erik and due to the shorter gearbox ratios, making acceleration a greater factor in the LM than the top speed(anyone remember Andy Wallace's LM 0-100-0 test in Autocar?......)

:thinkerg: There was actually a thread dedicated to this question here - http://www.automotiveforums.com/vbulletin/showthread.php?t=451991

Mind you, stick an LM motor in a road-going non-HDF-kitted F1, take off the wiper, sticky-tape the shutlines on the bonnet and over the indicators as per the original top speed run and i am sure this would beat 240.1mph...... ;)

Whats the performance figures of #073?
Has anyone tested that car?

...and due to the shorter gearbox ratios, making acceleration a greater factor in the LM than the top speed.

Ahh yeah - neglected to mention that. Thanks!

And no tests of #073 to my knowledge and I doubt there ever would be unfortunately.

>8^)
ER

How about an F1 GT Road car with an LM spec engine, with the rev limiter removed. Perhaps we shall never know!!! 250 mph plus with the correct gearing.

I've read in a few places that the top speed for the LM Is 230 or even 235, but 225 seems a bit more accurate.

I've also read that is has a 0-60 of 2.9 seconds, which seems like it could be true but some sources say otherwise. Not trying to go off topic, but what is the actual number?

I've read in a few places that the top speed for the LM Is 230 or even 235, but 225 seems a bit more accurate.

I've also read that is has a 0-60 of 2.9 seconds, which seems like it could be true but some sources say otherwise. Not trying to go off topic, but what is the actual number?

The LM was used by CAR Magazine when they broke the world record for 0-100mph, doing it in 6.1 seconds. The car also reached a record by doing the 0-100-0 mph in 11.5 seconds being driven by Andy Wallace (Ex Harrods GTR Race Driver). This record has now been broken by the Ultima GTR and perhaps one more?........In this test though, it was stated they measured the 0-60 time as being 3.9.......:screwy:

http://www.supercars.net/cars/1180.html - agrees with you though Mclaren F1 Guy, at 2.9sec 0-60mph

In this test though, it was stated they measured the 0-60 time as being 3.9.......:screwy:2.9s is the time if you can get a good launch. The LM is so light and powerful that it was difficult for the driver to do it in less than 3.9s.

This is a really debatable subject - but the (non-LM) production car top speed is not really 240.1 (IMHO) - the car that did that speed was modified by the factory (the rev. limit was removed/raised) and therefore not a "standard" production car.
While raising the rev. limit is not really cheating, as it's not increasing the performance per se, a customer could not do it. Also, I understand (it's been debated here before) some of the shut lines were taped up and the wiper removed (I think).

No standard F1 road car will reach anything like 240.1 (not that it's a problem). My friend did 221mph in his and it was on the rev. limiter. With newer tyres there is maybe a few more MPH to be had - 225mph perhaps. That is still an awesome speed, no question.

The factory will not raise/remove the rev.limit on request.

Apparently doing a Vmax run in an F1 is very rare for an owner - my friend was told, I seem to recall, that he was the only one the factory was aware of who'd done it.

Any car with HDF is going to be slower still.

Anyone got a listing of the engine specs and gear ratios between standard and LM handy?

I dout about the LM or GT top speed performance...
1. It reduce the Rev limiter
2. It Reduce the wight
3. Engine Performance level been improve....

The Ferrari F40LM for example ,it has reaching 370km/h compare to normal F40 did 325 Km/h ,it reduce wight of the car ,it has bigger turbo ,intercooler etc

a.same thing with higher down force level on the LM version and around 1000Kg of wight ....someone please correct me ,if i wrong......

b.If there is a limit for the car . it must be the racing "short" gear ratio ...
The LM would not reach 240.1 mph due to the drag created by the rear wing and front spoiler which add additional downforce. My guess is that an LM would be good for roughly 220-225 mph maximum.
I understand those extra Down force will pull down the top speed , but as it Rival F40LM can reach 230mph ,whats the point to Create a race car with lower speed ?

b.If there is a limit for the car . it must be the racing "short" gear ratio ...
I understand those extra Down force will pull down the top speed ,

but as it Rival F40LM can reach 230mph ,whats the point to Create a race car with lower speed ?On most circuits you can't take advantage of a car's top speed. Therefore, cornering and midrange acceleration become the key ingredients for winning a race. Additionally, weight improves acceleration, but doesn't really affect top speed.

Slightly off topic: I would hardly call the F40LM a rival for the F1. The highest place of any Ferrari in the 1995 LeMans was 12th, and NONE of the Ferraris entered in the 1996 LeMans even finished. The F1, however, won the 1995 LeMans, and finished very successfully in 1996 and 1997. Purpose built race cars like the 911 GT1 and CLK-GTR were the F1's rivals, not the F40.

Production F1
- 1140 kg
- 627 bhp
- 651 Nm
- 7500 rpm
- 225 mph (240.1 mph with no rev limit)

F1 LM
- 1062 kg
- 680 bhp
- 703 Nm
- 8500 rpm
- 225 mph (according to Driving Ambition)

F1 GTR (1997)
- 915 kg (wow - that's light - what did they take out?)
- 600 bhp
- 506 lb/ft
- 7300 rpm
- 215 mph (according to Driving Ambition)

Hey Joe911, you said your friend has an F1! Would you mind telling us any information like color, location, chassis number...? Thanks! :cheers:

Hey Joe911, you said your friend has an F1! Would you mind telling us any information like color, location, chassis number...?
He's Flemke from PistonHeads - the car is blue with high mirrors and in Europe. There are quite a lot of details about the car been posted on the PistonHeads forum. I think there was a pictures thread on here too.

Production F1
- 627 bhp
- 225 mph (240.1 mph with no rev limit)

F1 LM
- 680 bhp
- 225 mph (according to Driving Ambition)

F1 GTR (1997)
- 600 bhp
- 215 mph (according to Driving Ambition)
Thanks to comments from my learned friend ...

The 680bhp LM engine is 1.084 times more powerful then the standard with the 627. For a given CdA, your multiple in max speed is the cube root of the increase in bhp. The cube root of 1.084 is 1.027. Therefore, if you put an LM engine in the standard body shape, your resulting top speed would be 1.027 (ish) times 240, or 246.5 mph, at best.

A standard road F1 with HDF will do, in fact about 190mph.

Another friend had an HDF car with an LM engine and it would do about 195 mph - which all adds up.

If you do the math for the lower power of the GTR - they would max out at about 186 mph.

Thanks to comments from my learned friend ...

The 680bhp LM engine is 1.084 times more powerful then the standard with the 627. For a given CdA, your multiple in max speed is the cube root of the increase in bhp. The cube root of 1.084 is 1.027. Therefore, if you put an LM engine in the standard body shape, your resulting top speed would be 1.027 (ish) times 240, or 246.5 mph, at best.I actually did some calculations a couple of months ago involving installing an LM engine into a standard road car. Here's the results if you're interested:

http://s94779296.onlinehome.us/McLarenF1/McLarenF1.html

They just fast aint they ? lol

I actually did some calculations a couple of months ago involving installing an LM engine into a standard road car. Here's the results if you're interested:
http://s94779296.onlinehome.us/McLarenF1/McLarenF1.html

Interesting numbers, thanks for sharing. The document says engine power is 698.4400 horsepower - and yet McL and BMW claim 680 - where did the 698 come from?

Interesting numbers, thanks for sharing. The document says engine power is 698.4400 horsepower - and yet McL and BMW claim 680 - where did the 698 come from?That's the necessary power output for the standard F1 to travel 251.8 mph speed, which is a bit of a problem because the LM engine is rated for a power of 680BHP @ 7800RPM. I first raised my eyebrows at it, but then I realized that this data is taken from a dynamometer.

Unlike top speed tests, dynamometer tests aren't conducted with air being forced into the intake at 240mph, they're conducted on test stand. This means that my over-estimate of the engine's ability isn't necessarrily a bad thing, because the LM engine might actually be able to crank out 698HP when the air is being forced in by a 240mph headwind.

Additionally, the 240mph run that the F1 did meant it was putting out 539 N*m of torque at the wheels @ 8300RPM. This, however is a gross overestimate of the engine's capability according to the dynamometer test data. Again, the 240mph headwind must improve the volumetric efficiency of the engine at high speed because it acts as a forced induction. In non-technical terms, this is a "ram-air" effect.

I have since updated the web page to include this effect.

Additionally, the 240mph run that the F1 did meant it was putting out 539 N*m of torque at the wheels @ 8300RPM. This, however is a gross overestimate of the engine's capability according to the dynamometer test data. Again, the 240mph headwind must improve the volumetric efficiency of the engine at high speed because it acts as a forced induction. In non-technical terms, this is a "ram-air" effect. This is the fact of race car been design this way , But still lots of people do not believe the force of nature.....

That's the necessary power output for the standard F1 to travel 251.8 mph speed, which is a bit of a problem because the LM engine is rated for a power of 680BHP @ 7800RPM. I first raised my eyebrows at it, but then I realized that this data is taken from a dynamometer.

Unlike top speed tests, dynamometer tests aren't conducted with air being forced into the intake at 240mph, they're conducted on test stand. This means that my over-estimate of the engine's ability isn't necessarrily a bad thing, because the LM engine might actually be able to crank out 698HP when the air is being forced in by a 240mph headwind.

Interesting.

Forgive my lack of maths and physics (which I did study 25 years ago but have forgotten nearly all of) - but the aim of your paper seemd to be to calculate the top speed. However, you seem to be assuming the top speed and calculating the engine power required to meet your number?

Your point about ram air seems relevant - however - I understood that some dynos do have the ability to add air to the equation (for valuable cooling as well as a more realistic air temperature/density scenario) - however I had assumed that whether some amount (maybe too little, maybe too much) of ram air was used that the derived engine power would factor it in.

I think you can assume that BMW and McL understand these things and factor them in. They say 680 bhp. Should that not be an input parameter to your equations, rather than an output?

i think I should remind about this topic , the power from wheels are diffrent, compare to direct power output from the engine .......all thats factor count...

i think I should remind about this topic , the power from wheels are diffrent, compare to direct power output from the engine .......all thats factor count...
Yes, of course - the figures being discussed are engine figures, not at the wheel figures (which are of course always lower).

Interesting.

Forgive my lack of maths and physics (which I did study 25 years ago but have forgotten nearly all of) - but the aim of your paper seemd to be to calculate the top speed. However, you seem to be assuming the top speed and calculating the engine power required to meet your number?
I think you can assume that BMW and McL understand these things and factor them in. They say 680 bhp. Should that not be an input parameter to your equations, rather than an output?If cars were operated on pure force alone, such as a jet engine, then I could simply use:

Power = 0.5 * Cd * A * density * V^3

However, cars must physically push from the ground, so I have to include the effects of gearing. The power that I calculate is based off of the estimated engine torque and the RPM where that torque occurs.

For cars in general: the actual top speed might not come at peak power, because the wheel speed is constrained by gearing. Some cars have 6th gears which are actually slower than their 5th gears, to promote good fuel economy. The F1 is one of the few cars where the highest gear will take it all the way up to its top speed, due to the almost linear power curve of the engine, and the gearing.

Your point about ram air seems relevant - however - I understood that some dynos do have the ability to add air to the equation (for valuable cooling as well as a more realistic air temperature/density scenario) - however I had assumed that whether some amount (maybe too little, maybe too much) of ram air was used that the derived engine power would factor it in.I don't doubt that that McLaren and BMW both have the capability to simulate 240mph air being fed into the engine, and this is often done for Formula 1 cars. However, I don't think this was done on the F1's engine: if you compare the dynamometer data to the F1's 240mph run, you'll find out that the dynamometer data just can't move the car at 240mph. There has to be some ram-air effect happening.

Remember, Murray only asked for a 550HP engine, but BMW gave him one that was slightly heavier and produced 627HP. He obviously designed the car's air intake to be in an advantageous position, but I doubt he sat down to figure out exactly what the effects of the ram-air would be. He also didn't purposefully make the F1 go 240mph, he just designed it to be his vision of the ultimate driver's car for the road.

i think I should remind about this topic , the power from wheels are diffrent, compare to direct power output from the engine .......all thats factor count...I account for this in my calculations. The F1 only needs about 602HP at the wheels to go through the air at 241mph. The engine is probably producing more than the quoted 627HP because of the ram-air effect.