Hello,
After a bit of research and a dash of experimentation I
have come up with the following relative values for the
various marques in GPL:
8.272 Cooper
8.124 BRM
8.037 Ferrari
7.991 Honda
7.638 Lotus
7.546 Eagle
6.919 Brabham
The values are in terms of frontal area (units of feet
squared, i.e. width times height) multiplied by coefficient
of drag (no unit, i.e. dimensionless). Since I have no
reliable info on frontal area and such info is rather hard
to get even in the real world I'm afraid it is hard to
break it down any further. Also note that the values
were obtained using the standard 'power to overcome
aero/rolling resistance' formula. Input was marque
weight and horsepower (taken from GPL screens),
terminal velocity (obtained experimentally within GPL)
and a constant of 1.0 for the frictional coefficient
component of rolling resistance. That and my
uncertainity about tranmission efficiency somewhat
diminish the accuracy of the results.
That said, the relative order should be correct. I find
it interesting that the cars differ so much as they all
used the pretty much the same profile tires which I am
lead to believe contributes the majority of the drag to
the drag profile. It is also interesting that the Brabahm
comes out on top as looking back through the photos it
seems to be the car the least concerned with frontal
aerodynamics. I realize it is a rather petit car, but
somehow I doubt Sir Jack could get the BT24 up to
197 MPH on it's own even if he did have the extra
20HP GPL has generously bestowed upon him.
On the other end of the spectrum the Cooper seem
to have been punished for an overestimation of the
marque's horsepower. True that front end looks
Texas sized, but I think in reality the Coopers lack
of top speed should have more to do with a lack of
horsepower from the Maserati V12 (did one ever make
390HP?) rather than a lack of an ability to cut through
the wind.
Does anyone have any information about how Papyrus
came up with the drag profiles for each of the marques?
I suspect much of it came about in an effort to meet
preconceptions about the relative performance of
each car followed by a late attempt to redress any
imbalances that showed up in testing.
Not that I'm complaining (sound of WinVROC being
launched in the background). ;-)
- George
um.... well you lost me after "Hello" :o)
"George M. Smiley" wrote:
> Hello....
--
Rob Swindells
//
http://www.robswindells.com
http://www.f1core.com
//
"Question: Why [is GPL], [one] of the best driving games ever made, so
hard to find and under-f*****g-appreciated? It's damn near criminal..."
~Frank
//
Uh... yeah, Brain, but where are we going to find rubber pants our size?
George,
Interesting stuff. In real life, there are some discrepancies. The
Ferrari, for example, seemed much cleaned up (aerodynamically) by Monza, and
the Cooper had benefited from further dev't work on its ancient 12-cylinder
engine (originally a 3-valve, 2.5-liter V-12 built for the last couple of
250Fs *11* years earlier!). Likewise the Repco, which moved the exhaust
manifolds between the cyl. banks late in the year for better aero. Yes, the
BT24 was "dirty", but it really was tiny, having been derived from the F2
BT23, so despite being down on power, it didn't have to poke much of a hole
thru the air. It proved its mettle at Monza by losing a drag race with
Surtees' powerful RA300 from the Parabolica to the checkered flag on the
last lap by less than 2/10ths of a second. The Brobdingagian BRM H-16 was
as dirty, huge, and heavy as the Honda, but seriously down on power (and
reliability). The Lotus was realtively small and clean. The Eagle was very
light (thanks to a lot of titanium parts), relatively clean, and quite
powerful. The best article I read on their relative performance was Road &
Track's race report from Monza that year. BTW, they all had wide variations
in tire sizes, but I don't know how Papy calculated the drag, much less the
hp. Of all the cars in GPL, I think the Ferrari got the shortest shrift.
I'd rank its high-end performance ahead of the Lotus.
--Steve Smith
George M. Smiley <[email hidden]> wrote in message
news:KMiR5.70$[email hidden]...
Quoted text (66 lines)
> Hello, > > After a bit of research and a dash of experimentation I > have come up with the following relative values for the > various marques in GPL: > > 8.272 Cooper > 8.124 BRM > 8.037 Ferrari > 7.991 Honda > 7.638 Lotus > 7.546 Eagle > 6.919 Brabham > > The values are in terms of frontal area (units of feet > squared, i.e. width times height) multiplied by coefficient > of drag (no unit, i.e. dimensionless). Since I have no > reliable info on frontal area and such info is rather hard > to get even in the real world I'm afraid it is hard to > break it down any further. Also note that the values > were obtained using the standard 'power to overcome > aero/rolling resistance' formula. Input was marque > weight and horsepower (taken from GPL screens), > terminal velocity (obtained experimentally within GPL) > and a constant of 1.0 for the frictional coefficient > component of rolling resistance. That and my > uncertainity about tranmission efficiency somewhat > diminish the accuracy of the results. > > That said, the relative order should be correct. I find > it interesting that the cars differ so much as they all > used the pretty much the same profile tires which I am > lead to believe contributes the majority of the drag to > the drag profile. It is also interesting that the Brabahm > comes out on top as looking back through the photos it > seems to be the car the least concerned with frontal > aerodynamics. I realize it is a rather petit car, but > somehow I doubt Sir Jack could get the BT24 up to > 197 MPH on it's own even if he did have the extra > 20HP GPL has generously bestowed upon him. > > On the other end of the spectrum the Cooper seem > to have been punished for an overestimation of the > marque's horsepower. True that front end looks > Texas sized, but I think in reality the Coopers lack > of top speed should have more to do with a lack of > horsepower from the Maserati V12 (did one ever make > 390HP?) rather than a lack of an ability to cut through > the wind. > > Does anyone have any information about how Papyrus > came up with the drag profiles for each of the marques? > I suspect much of it came about in an effort to meet > preconceptions about the relative performance of > each car followed by a late attempt to redress any > imbalances that showed up in testing. > > Not that I'm complaining (sound of WinVROC being > launched in the background). ;-) > > - George > > > > >
"Stephen Smith" <[email hidden]> wrote:
> It proved its mettle at Monza by losing a drag race with
> Surtees' powerful RA300 from the Parabolica to the
> checkered flag on the last lap by less than 2/10ths of
> a second.
No disrespect to the improved Monza 'Hondola', but Surtees
seemed to have a hard time pulling away from the stricken
Ferrari of Amon so I'm not sure I would classify the Honda
as 'powerful'. From every account I have read it never
produced anywhere near the power Honda claimed it
did. Sir Jack certainly played the draft for all it was worth
at Monza though.
> BTW, they all had wide variations in tire sizes
I've now been told that the Brabham BT24 ran 15 inch
diameter front and rears with 8 inch width fronts and
10 inch width rears. The Lotus ran the same diameter
but with 8 or 10 (usually 8) inch width fronts and 13
inch rears.
I also found a while back that Ferrari lists in detail their
F1 car specs, for the '67 312 F1 the URL is:
http://www.ferrari.it/comsport/formula1.e/312f167.html
If I am interpreting their specs correctly, they too ran
the same diameter tires only with 10 inch width fronts
and 12 inch width rears. Interesting to note that very
little agrees with that which is listed in GPL. Ah, the
vagaries of simulation research!
Can anyone elighten us as tire widths to the other
marques? If not, take a tape measurer with you next
time you vist an automobile museum. ;-)
- George
