McLaren F1 Vehicle Dynamics

As many of you know, the McLaren F1 was tested on Anthony Best Vehicle Dynamics' K&C rig. Only the bounce frequencies of the front and rear were reported, however; I'm wondering if anyone here knows the wheel rates, damping factors, roll stiffness and center of mass height for the F1. Any information would be immensely helpful.

On a hunch, are you a game developer?

If so, and if you have license from McLaren to include the F1, then can't they supply you with this level of detail directly?

Trying to think of where any of that might exist in reference material I would have, and unfortunately I'm doubtful it's been published.

>8^)
ER

I'm not a gave developer, no. I'm an engineering student. I'm trying to develop a model for pitch, roll, yaw etc. for the McLaren F1

Gotcha - I'm thinking if anyone here could assist it would be Le Man or M.S.O if they are able.

McLaren may consider some of that data sensitive or proprietary - hard to be sure.

>8^)
ER

Let's hope they notice this thread and offer their assistance. Unless I could try contacting them somehow.

The forum has a Private Message feature - you could try that approach and point them here to the thread.

>8^)
ER

Alrighty, I'll give that a shot.

Gotcha - I'm thinking if anyone here could assist it would be Le Man or M.S.O if they are able.

McLaren may consider some of that data sensitive or proprietary - hard to be sure.

>8^)
ER

You need a copy of the IMechE paper by Steve Randle, the vehicle dynamics engineer for the F1.

Concept and design of the McLaren F1 suspension systems
IMechE paper C466/007/93

This paper is very indepth on the subject of the F1,s vehicle dynamics and will certainly help you with your studies.

If you have a problem obtaining a copy, give me a PM with your email address and I shall send you the info.

Sounds like I need a copy too - I wasn't aware of this or missed it if you shared it previously Le Man. Off to look... :)

>8^)
ER

Sounds like I need a copy too - I wasn't aware of this or missed it if you shared it previously Le Man. Off to look... :)

>8^)
ER

Yes, you have a copy, long time ago.

One cool place that i found some hidden information is contained in Driving Ambition, page 127. It is some hand written notes from Gordon Murray pertaining to targets for the vehicle. It had a target of:
wheel travel = +80 -90 F&R
Ride Frequency = 80/92 cpm
Roll Axis Centroid = roll center 60 mm a. ground @ F. 90 mm R.
Anti-Roll Bars= Front only
Roll Stiffness = 3 degrees per g lat
Anti-Dive = Yes (40-50%) investigate farb
Anti-Squat = ?
Damping = aluminum shocks[?] - ride ht adj?
velocity ratios = as near 1:1 as poss. (same F&R) + rising rate
Camber Change = 75% of body roll = 4.4 degrees for 80 mm travel
Wheel size = 18" dia x 8.5" F x 11.5" r
Tyre size = 245x40x18
Wheel base = 104" (2640)
Track = 1800 over tyres F&R [corrected to 1554]
Front Offset and Trail = Offset 14 mm @ gr, trail 30 mm
KPI = 10 degrees [corrected to 9 degrees]
Castor = 4 degrees
Static Camber = -45' F&R
Toe In = 3mm neg. F O F
Bump Steer = None
Center of pressure = 57% of wheel base
CD = .330
CL Front and Rear = .150 F .150 R (stable in yaw)
[something off the page] torsional stiffness = 10,000 ft lb/degree axle to axle min
Steering Wheel Diam = 13" dia
Unsprung Weight = 37 kg F 49 R
Frontal Area = 1.62 m^2
CDA = .535
Ground Clearance = 120mm
Ackermann Characteristics = 0-5 degrees / 0% 5-10 degrees / 35% 10-20 degrees / 80% -> 100% From [?] 25 degrees

I know some of that is contradictory to some other sources, like "Mclaren's Road Car an Autocar & Motor Book" claims the KPI is 8 degrees not 9, and the castor angle at 4.6 in lieu of 4. It also states that the ground level offset (the distance between the centre-line of the type and where the steering axis meets the ground) is 25 mm.

Unfortunately that is about all I can contribute at this time....hope it helps some.

Le Man I would be interested in that paper if you are willing to share. The engineering feat that is the McLaren F1 never ceases to amaze me.

Excellent! I PM'd Le Man for the paper. Hopefully he can send me a pdf or the images.

You need a copy of the IMechE paper by Steve Randle, the vehicle dynamics engineer for the F1.

Concept and design of the McLaren F1 suspension systems
IMechE paper C466/007/93

This paper is very indepth on the subject of the F1,s vehicle dynamics and will certainly help you with your studies.

If you have a problem obtaining a copy, give me a PM with your email address and I shall send you the info.
Hey Le Man do you know the lift coefficient,rear wing dimensions(height and wingspan) for the Mclaren F1 LM.I need it to verify the info given in CAR Magazine that is it can run upside down at 100mph.

Thank You

Hey Le Man do you know the lift coefficient,rear wing dimensions(height and wingspan) for the Mclaren F1 LM.I need it to verify the info given in CAR Magazine that is it can run upside down at 100mph.

Thank You

I'm going to go out on a limb and say that I don't think there's a road car that generates enough downforce to overcome its own weight. I've only heard of that anecdote about Formula 1 cars. If I'm wrong I'd love to hear otherwise.

Even an extremely aggressive aero package would struggle to produce anything close to 2,000 lbs of downforce at 100mph. Doubling that speed would change the story.

>8^)
ER

I'm going to go out on a limb and say that I don't think there's a road car that generates enough downforce to overcome its own weight. I've only heard of that anecdote about Formula 1 cars. If I'm wrong I'd love to hear otherwise.

Actually there is one another car I have heard capable of doing that.It is saleen S7 which is said to produce downforce equal to its weight at 160mph.But I think that that amount of downforce will make the handling dangerously unpredictable.
http://www.caranddriver.com/reviews/saleen-s7-twin-turbo-road-test-scorching-performance-page-2

I think that F1 GTR and current GT3 racecars can create that amount of downforce(in high downforce configuration) at 100mph but it is a race car.But for LM I think it is just crazy high.

That's an interesting article about the S7. It's a small enough production run that they could go with extreme aero so it seems believable. I actually just found a database that lists downforce numbers for quite a few race cars and a few road cars and has references for the numbers. The F1 GTR is listed with 1776lbs at 180mph which would not be enough to negate its weight. Some other interesting spoilers: a VW Beetle generates 742lbs of lift at 124mph, and a Sauber C9 almost 4000lbs of downforce at 180mph.

http://www.mulsannescorner.com/data.html

That's an interesting article about the S7. It's a small enough production run that they could go with extreme aero so it seems believable. I actually just found a database that lists downforce numbers for quite a few race cars and a few road cars and has references for the numbers. The F1 GTR is listed with 1776lbs at 180mph which would not be enough to negate its weight. Some other interesting spoilers: a VW Beetle generates 742lbs of lift at 124mph, and a Sauber C9 almost 4000lbs of downforce at 180mph.

http://www.mulsannescorner.com/data.html
I doubt that info is incorrect.Because F1 GTR Longtail has laptimes faster than Stefan Bellof's 956 Group C car in most of the circuit.We all know that Group C must be faster in straightline for F1 GTR to set faster laps,it must be faster in corner.Anyway here is that article that states F1 LM can run upside down at 100mph.
http://www.motortrend.com/news/2000-mclaren-f1-supercar/

Hey Le Man do you know the lift coefficient,rear wing dimensions(height and wingspan) for the Mclaren F1 LM.I need it to verify the info given in CAR Magazine that is it can run upside down at 100mph.

Thank You

Ever wondered why nobody has ever attempted this feat?

Does not matter if you could create enough suction to stick the car to the roof/ceiling of a tunnel etc. No IC engine will run for long enough upside down before its oil runs dry from the crank and drowns the valve train etc.

Would make great YouTube viewing watching people try.

F1 engineers, journos etc should know better to keep crazy ideas where the sun does not shine.

Yes I do have the rear wing data, but you need lots more info than that for your equations.

The is one way to maybe, just maybe, solve this. Let's look at the Sport Auto Supertest. As we all know, every month or so, Sport Auto runs a sports car through a battery of tests. One of these tests is, of course, a wind tunnel test.

By far, the best performer in terms of total downforce is the Gumpert Apollo S, which made a total (total!) of 196 kg (1930 N) of downforce at 200 km/h. Assuming drag and lift forces scale with the square of speed (this is not 100% accurate, but for the short range of speeds we're dealing with, it'll do), we can find the Gumpert's downforce at 100 mph (approximately 160.93 km/h):

downforce at 100 mph = (160.93 km/h / 200 km/h)^2 * 1930 N

downforce at 100 mph = 1250 N or 127 kg

From Driving Ambition, we know the 1995 F1 GTR has a mass of 1050 kg (1120 with a 70 kg driver).

At 100 mph, the Gumpert Apollo S produces around 11.3% of the force necessary to hold an F1 GTR upside down. Is it likely that the F1 GTR produces around 9 times the downforce as the Gumpert Apollo S? Possibly. But I have my doubts.

Ever wondered why nobody has ever attempted this feat?

Does not matter if you could create enough suction to stick the car to the roof/ceiling of a tunnel etc. No IC engine will run for long enough upside down before its oil runs dry from the crank and drowns the valve train etc.

Would make great YouTube viewing watching people try.

F1 engineers, journos etc should know better to keep crazy ideas where the sun does not shine.

Yes I do have the rear wing data, but you need lots more info than that for your equations.

I have other required values please give me the rear wing dimensions those are the only values I am left with.

Was digging around on Mulsanne's Corner, came across this:

http://www.mulsannescorner.com/aerodatabasemclarengtr97.html

Still looks like it cannot drive upside down at 100 mph, however.

But I doubt that those figures are wrong.In spa the longtail version was faster than Stefan Bellofs Porsche 956 1984 version group c version.
http://www.racingsportscars.com/results/laps/Spa-1984-09-02.html
http://www.racingsportscars.com/results/laps/Spa-1997-07-20.html
Even 96 version of F1 GTR could lap around just 2s slower than LMP of its time.So unless we know the wing dimensions we cannot verify the info.

Had myself a subway ride to the library this weekend and thought I'd share. This is from Competition Car Aerodynamics by Simon McBeath.

Had myself a subway ride to the library this weekend and thought I'd share. This is from Competition Car Aerodynamics by Simon McBeath.
Thank you for sharing that book.But I find some of the information wrong.The topspeed for F1 GTR was 205mph at Le Mans 1996 but the book states it as 198mph and F1 car during that time generate more downforce(I am assuming it because it has lower downforce in the book even than an LMP with low downforce configuration) than specified in the book and had more topspeed than F1 GTR.

Feel free to correct me if I am wrong about wing specifications which I found by taking proportions from the photos of F1 GTR:naughty::naughty:

Wing Span =1.79m
Height of wing=0.44m
coefficient of lift(from the book rusty shared)=0.34
Angle of attack(assuming from the rear wing photo)=27degree

So downforce at 100mph(44.7m/s) I got from calculation by using formula from wikipedia is
1/2*1.79*0.44*0.34*27*44.7*44.7N*1.25=9029N
So it is around 921kg at 100mph.I think it may not run upside down at 100mph CAR magazine may have used exaggeration in that statement.

The Angle of attack must be in radians, not degrees. Assuming the formula you're using is

downforce = 0.5*v^2*height_of_wing*angle_of_attack*wingspan*co efficient_of_lift

If this is the case, you get 126 N. You must also multiply by the density of the air (source: https://www.grc.nasa.gov/www/k-12/WindTunnel/Activities/lift_formula.html)
This adjusts the number to 151 N (assuming an air density of 1.2 kg/(m^3)).

Furthermore, the value quoted in the book was for the overall car, which uses the cross-sectional (frontal) area of the car (1.58 m^2, according to the book; although it's more than likely around 1.79 m^2 - closer to the roadcar) as the reference area, as opposed to the area of just the wing. If this is the case, you can expect 644 N (1.58 m^2) or 730 N (1.79 m^2) of downforce.

It is also worth noting that the book claims the F1 GTR was producing "600 lb. to 1500 lb. (273 kg to 682 kg)" of downforce, but does not mention a speed. It does, however compute a lift-to-drag ratio of -0.6:1, which is reproduced by taking -0.34 (the overall lift coefficient) to 0.57 (the overall drag coefficient), indicating that the lift and drag force equations use the same reference area.

The Angle of attack must be in radians, not degrees. Assuming the formula you're using is

downforce = 0.5*v^2*height_of_wing*angle_of_attack*wingspan*co efficient_of_lift

If this is the case, you get 126 N. You must also multiply by the density of the air (source: https://www.grc.nasa.gov/www/k-12/WindTunnel/Activities/lift_formula.html)
This adjusts the number to 151 N (assuming an air density of 1.2 kg/(m^3)).

Furthermore, the value quoted in the book was for the overall car, which uses the cross-sectional (frontal) area of the car (1.58 m^2, according to the book; although it's more than likely around 1.79 m^2 - closer to the roadcar) as the reference area, as opposed to the area of just the wing. If this is the case, you can expect 644 N (1.58 m^2) or 730 N (1.79 m^2) of downforce.

It is also worth noting that the book claims the F1 GTR was producing "600 lb. to 1500 lb. (273 kg to 682 kg)" of downforce, but does not mention a speed. It does, however compute a lift-to-drag ratio of -0.6:1, which is reproduced by taking -0.34 (the overall lift coefficient) to 0.57 (the overall drag coefficient), indicating that the lift and drag force equations use the same reference area.

Thank you for correcting me but the angle of attack is used in degree.The source is an engineering book where they calculate downforce for formula one cars when they can travel upside down.

About the wing dimensions I got wing span by taking ratio of width and the wingspan in the topview diagram of F1 LM from driving ambition book I attached and height by taking ratio's of height.

(It is also worth noting that the book claims the F1 GTR was producing "600 lb. to 1500 lb. (273 kg to 682 kg)" of down force, but does not mention a speed).

I am sure it says somewhere that the speed was 100mph or it may have been in a magazine article on the LM?

The 100 mph was from Car Magazine. It is implied (I suppose) that the speed was 200 mph, but never explicitly stated as such on the text.

The 100 mph was from Car Magazine. It is implied (I suppose) that the speed was 200 mph, but never explicitly stated as such on the text.
But you should remember that the test driver was Andy Wallace and anything he says is believeable because he has driven the car in le mans and BPR Global GT.So he may be aware about the figures more than we do.You can't be competitive with a racecar with only 1000kg downforce at 200mph.Even Saleen S7 roadcar will have more downforce in that case.

Oh, I'm not disputing the claim. I'm just try to clear up the confusion about where the 100 mph figure came from.

That said, we have two sources which are at odds with each other. Andy Wallace (a very reputable source, as he's driven at Le Mans for McLaren and was even the driver who pushed XP5 past 390 km/h at Ehra-Lessein); and Competition Car Aerodynamics by Simon McBeath, which, while it doesn't quote a source (I don't think) or a reference speed, appears to be legitimate and well-researched.

It might be a question of set-up, too. To be honest, I'm really not sure which one to believe. I just don't have all the information.

You also have the added complication of different wing configurations not only between 1995 and 1996 cars but also different races.

Agreed. Even if the McLaren F1 GT/GTR/LM couldn't produce 9807 N (1000 kg) of downforce at 100 mph (and I'm not completely sure either way), that just wouldn't matter. The McLaren F1 is still an amazing achievement, and it always will be.

Oh, I'm not disputing the claim. I'm just try to clear up the confusion about where the 100 mph figure came from.

That said, we have two sources which are at odds with each other. Andy Wallace (a very reputable source, as he's driven at Le Mans for McLaren and was even the driver who pushed XP5 past 390 km/h at Ehra-Lessein); and Competition Car Aerodynamics by Simon McBeath, which, while it doesn't quote a source (I don't think) or a reference speed, appears to be legitimate and well-researched.

It might be a question of set-up, too. To be honest, I'm really not sure which one to believe. I just don't have all the information.

Well if you read the Competition car aerodynamics carefully,you will understand that they used a lot of assumptions in calculating downforce like it produces 15% of downforce of an F1 car in low downforce configuration.If I am correct even standard F1 may produce 600kg at 250km/h(I may be wrong too).Because it could take a corner meant for 200km/h at 250km/h while cars like Veyron was struggling to take the curve at 206km/h according to the Ehra Lession video.I think the downforce figures in the engineering book may be for low downforce configuration and may be quoting rear downforce values at best.

I agree with you even if F1 GTR doesn't produce that much downforce,it is a great car because there is no other true GT1 car of that time which can atleast match the laptimes of modern LMP2 car(even the shorttail version).There is no other GT car which has won Le Mans in its debut.:grinyes:

And not to mention that even the standard F1 is still considered as a benchmark car by many.It beat Enzo in bedford track,it has done 7:22 at nurburgring according to estimates from Circuit Breaker Article,it beat CGT at Goodwood track when tested by Rowan Atkinson.We won't see such a wonderful car unless Gordon Murray designs a new supercar.I think even he may not surpass it.Even if P1 beats it in any test,we will not have such a legend.