rec.autos.simulators

But I've noticed something, looking on technical F1 sites I found that the
wings should provide about 60% of the cars downforce with the front about
25% and the rear 35% (I know that would vary allot depending on settings).
But as far as I can make out even at their maximum settings the wings only
account for about 30% of the cars downforce in F12001. The rest is made up
by the body at about 25% and the diffuser at a whopping 43% that can't be
right?

Also the downforce loss with lower wing settings is way too extreme imo, at
the lowest wing setting the downforce is virtually zero, that's just not
right the lowest wing setting on an F1 car will still produce allot of
downforce. That must be why everyone uses unrealistically high wing settings
everywhere because there's too much of a penalty for lowering the wings, and
far too extreme a range. 50 clicks is 50x the downforce of 1 click, there
can't be more than a 3-4x difference in downforce produced by the wings
between the highest and lowest settings on an F1 car (I'm guessing there).

Have I got totally mixed up or are the physics values (downforce at least)
of F12001's cars wrong? I've convinced myself they are and I'm trying to put
them right the best I can and it's starting to feel better already :-)

Alex

You're completely right, I've been tinkering with them myself as well and
came to the same conclusion.

Furthermore I felt that the overall downforce was way too high, I went back
to far lower values making the car more realistic through high speed
sections.

The problem however is that the AI has some sort of downforce 'trick' in
there, they always have higher downforce than us. And I also found out why,
when you give them very little downforce, they can't handle the tricky car.
So they slowdown in the middle of a fast corner. That's probably why they
decided on giving them some extra downforce over the player. It could also
be to get close to real world lap times.

Alex,

IIRC, those values would be pretty close. I believe in David Tremayne's book
_The_Science_ of_ Speed_ quotes similar values. compiled with the help of
Gary Anderson, then of Jordan, circa 1997/98. Actual %: 25, 33,42

Averaging the downforce coefficients and downforce/drag ratios calculated by
Enrico Benzing for a 750bhp car in Giorgio Piola's
_Formual_1_Technical_Analysis_2000_ book: 1606 kg, 2.95 respectively.

HTH,
j-n

I disagree about lowering the grip.  Low speed cornering is right where
it should be as far as I can tell.  I believe there is a problem in that
there are still an awful lot of people who think that F1 2001 works
properly in split axis mode, but it doesn't.  So they end up with a 50%
dead spot on the throttle without realizing it, and wonder why they
can't control the car at low speed.  Obviously I don't know if you are
having that difficulty or not, but I do know that once I went back to
combined axis control, thus getting rid of the dead spot, my low speed
cornering problems nearly disappeared (they didn't completely disappear,
because I'm not that good a driver :o)

I don't think that is correct.  There is no lift value for the body in
the hdv files, only for the wings and the diffuser.  And I think those
percentages are in reference to a race trimmed vehicle.  The basic lift
values in the hdv files are for zero wing setting and zero ground
height.  If you look at the comments in the file it is clear that in
race trim the wings will have more downforce than that base value and
the diffuser will have less.

there).

Again I think this is incorrect.  As I read the hdv files, the lift
value is given by a second order polynomial function of wing setting,
plus a height factor.  For example, the front wing lift for the Williams
would be:

CL = -0.4678 - 0.0111 * S + 0.00001 * S^2 + 1.005 * H

Where S is the wing setting and H is the height off of the ground in
meters.  That means the difference in CL from a setting of 0 to a
setting of 50 is about 0.53 (assuming I pressed the keys on the
calculator correctly :).  IOW the max wing setting has just over double
the downforce of the minimum one.

While I don't have any race car tuning experience, I do have 12 years
experience in automotive aerodynamics, and based on that I think the
values in the hdv files, correctly understood, are quite reasonable.

BodyFore=(0.0, -0.5252, 0.435)  // aero forces from moving forwards (lift
value important!)

I had misinterpreted the settings especially the wings, I've got a better
understanding of them now and a race trimmed car with 30 clicks of wing on
each end the wings roughly account for 48% and the body/diffuser 52% that is
still quite wrong. The wing percentages are 26% front 21% rear, remember it
should be 25% front 33% rear.

They may be perfectly right, but as F12001 is I just don't enjoy it I'm
doing it to get the car to feel the way I want and using the excuse that it
might be more realistic ;-)

Alex

Frustrating yes, but have you checked the speeds against real world
telemetry?  They come out about right to me at most of the tracks that I
have tried.

Very strange.  I believe you are correct, but it's odd that the third
value in there doesn't match the drag coefficient.

Just curious, have you tried combined axis pedals?  I didn't believe I
had the problem either until I tried it, and I have gotten the same
reaction from other people.  If you haven't tried it please do, I think
you will be surprised at the result.

OK, I have the same issue, but I don't find it to be a huge problem.  In
fact, before you mentioned it, everything seemed fine to me.  I think the
thing is, I only play F1-2001 - no other sims.  Because of that, I have
simply adjusted to this, to the point where I can control my car naturally.
I did a test a few minutes ago, and I was able to maintain any speed I
wanted to, within 5mph.  And that was low-speed stuff, too - 25-75mph.

Sure, there may be an argument that with the deadzone it's too easy to spin
your car, due to misjudging where the throttle comes "on", but that just
makes it more important to apply the throttle carefully.  At least, that's
what it's forced me to do.  I don't see that as necessarily bad...

I wonder - do you brake with your right or left foot?  I left-foot brake,
which means both my feet are always on the pedals.  That may make the
difference, esp. during transition.  During braking, my right foot eases off
the gas, but my foot's still on the pedal, at the proper take-up point.  If
you right-foot brake, yeah - of course it would be difficult, as you're
putting your whole foot back on the gas...

BTW, are you using throttle help?  That would definitely make

Throttle assist?  Well, typically no, although enough of the community is
using it in the interests of "realism" (traction-control) that I have been
been experimenting with running with it on low, but only lately.   Before
two weeks ago, I had been driving without it for two years...

D'oh.  If you wanted to use split-axis, you'd almost have to left-foot
brake.  My bad...