Quote from Bob Smith :

For another example:

You can ignore coefficients of friction (and therefore tyre dimension, number of tyres, and tyre load sensitivity) and working simply from lateral gs for the purposes of this question (or longitudinal, it doesn't matter, so long as you are consistent).

Without downforce (or just when moving very slowly), your F1 car is going to pull ~1.5g in the bends. It has a mass of 600kg, so on earth your total grip will be 600*9.81*1.5 = ~8800N.

With downforce, and travelling ~200mph, it can now pull ~4.5g in the bends (despite a reduced coefficient of friction, but we'll not go into that now). Thus using the same formula, the total grip now becomes 600*9.81*4.5 = ~26500N. Which is a lot. But is it more than a truck?

Trucks don't have (appreciable) lift or downforce, I'd say could only pull 0.6g in the bends, but are rather massive. So that makes it 8500*9.81*0.6 = ~50000N. Twice as much as an F1 car, even at 200mph. Ergo truck wins. And that was just taking the mass of the cab. Add your trailer and 20 tonnes of payload and grip is massive.

So the only thing making the F1 car perform better is inertia of mass, right?

Basically, yes



(Less basically, no)

Don't be shy, elaborate!

This is when

Quote :

coefficients of friction (and therefore tyre dimension, number of tyres, and tyre load sensitivity)

comes into play...

Quote from bbman :

So the only thing making the F1 car perform better is inertia of mass, right?

Yes. The maximum speed is also limited by the speed of the light (very very light things).

Ah, I thought Bob meant we can discount it altogether as it would equate to a constant value...

Basically there are 3 ways to define "grip" that make some sort of sense:

1) maximum cornering force achieved, which as such is allmost completely useless
2) coefficient of friction; rather hard to compare as it´s constantly changing, but its useful if you want to decide which tyre to choose
3) maximum g; now theres a number that can be used to compare almost any setup, car, whatever to whatever you´d like to use as a reference, up to and inclusing the maximum cornering g a chicken crossing the road can achieve

I consider grip to be absolute, whereas the coeffient of friction (or grip) is relative. Peak lateral gs is an acceleration and I wouldn't want to confuse that with the term "grip", although I agree it is the most useful figure of the bunch.

is there slipstream in this game?

Quote from atlantian :

is there slipstream in this game?

Yes but it is basic. Apparently the car in front does not get any of the slipstreaming effects...

so it would help me to tailgate someone?

Quote from atlantian :

so it would help me to tailgate someone?

Yes, you can be a bit faster in someone's slipstream but you will have less grip so in corners you need to be more careful.

In case anyone's (still) interested, here are some lift/downforce figures quoted from "Sport Auto":

997 Turbo:
f -8kg, r +12kg

997 GT2:
f +9kg, r +29kg

Gallardo Superleggera:
f -14kg, r -9kg

599GTB:
f -41kg, r -24kg

Audi R8:
f -7kg, r +1kg

Z06:
f -49kg, r -22kg

Audi S5:
f -52kg, r -34kg

BMW M3:
f -10kg, r -23kg

f=front axle
r=rear axle
a "-" in front of the number indicates lift
a "+" indicates downforce
all @ 200km/h

I'm surprised that the GT2 has downforce at the front.