OV9

nuttinnew wrote: Thu Feb 16, 2023 6:23 pm

Jobbo wrote: Thu Feb 16, 2023 5:52 pm

Jimmy Choo wrote: Thu Feb 16, 2023 3:36 pm Mik, none of us bothered to read any of that.

I still have that copy of Fast Lane so read it in the 1980s. So for at least 35 years it's been better without the rear wing and that won't change.

Does it mention anything about lift or stability?
(I've probably got a copy...somewhere...).

Yes. Martini notes that the wing lifts the nose and decreases stability at speed.

I thought the wing originally provided too much rear downforce and lifted the front of the car as it acted as a pivot - a problem also encountered by the last XJR due to fitting the third brake light in the rear wing.
So to fix this they redesigned the wing with 0 degree angle so it would be neutral and no longer provide downforce.

Ideally a front splitter would have fixed the problem but they didn’t exist back then?

Thanks Jobbo.

mik wrote: Thu Feb 16, 2023 6:25 pm

nuttinnew wrote: Thu Feb 16, 2023 6:23 pm
Does it mention anything about lift or stability?
(I've probably got a copy...somewhere...).

Yes. Martini notes that the wing lifts the nose and decreases stability at speed.

I meant as standard/without wing. I remember comments that the Miura's front got light at speed and that people tended to ease off before it had run out of oomph but the only thing I can recall of the Countach is ~ish as you said and that they got the hang of mounting the wing so that it had minimal (if any) effect. I'll have to google a few things.
Mind you, ignore the aero effects, I've always had an image of the wing weighing a tonne and plonking it on made it squat and the nose point skywards, and that's what caused the problems.

I can't find a wind tunnel look at the Countach
I'm hoping someone's done a simulation, or an aerodynamicist has done a Frank Stephenson on it.

Jobbo wrote: Thu Feb 16, 2023 5:52 pm

Jimmy Choo wrote: Thu Feb 16, 2023 3:36 pm Mik, none of us bothered to read any of that.

I still have that copy of Fast Lane so read it in the 1980s. So for at least 35 years it's been better without the rear wing and that won't change.

The Anniversary's main crime is the rear lights, IMO; the rest of the changes aren't too awful in themselves but the taillights are so wonderful on all Countachs up to and including the QV that sticking some which look borrowed from a van in a plastic surround is utterly bizarre.

The rear lights are the same ( nicked from a 70s Alfa Romeo Alfetta saloon ) but yeah, swapping the big red surround which looked great in the chopped off rear quarters for a big slab of body coloured plastic was a bad choice.

Loosely related tweet (as in not related, except for Countach content).

Apparently this happened in April in Japan - Walter Wolf's old Countach. Shame.

It'll probably get rebuilt, how original was it before?
A reply from Chris Goffey as well, so someone linked;

Good to revisit and check I chose option 3 when this thread started. I have just seen this about the Cannonball Run car, as the film turns 45:

https://www.lamborghini.com/en-en/news/ ... s-turns-45

So the extra wing on the front was for the movie rather than a factory US spec option. I guess it may have become something fitted for the US due to the popularity of the film, though I've never seen 12 exhausts on any other Counach

Jobbo wrote: Thu Jun 20, 2024 11:26 am Good to revisit and check I chose option 3 when this thread started.

So you were one. Who were the other two maniacs?

Jobbo wrote: Thu Jun 20, 2024 11:26 am Good to revisit and check I chose option 3 when this thread started. I have just seen this about the Cannonball Run car, as the film turns 45:

https://www.lamborghini.com/en-en/news/ ... s-turns-45

So the extra wing on the front was for the movie rather than a factory US spec option. I guess it may have become something fitted for the US due to the popularity of the film, though I've never seen 12 exhausts on any other Counach

I'm sure it was on Vinwiki that the current owner discussed the history on the car in detail and the wing thing being something to do with Cali legislation having to be added by the importers (pre-horrible rubber bumpers or something) and nothing to do with make-up. The 12 exhausts and antennas were mentioned as being added for the film, just because like they say make-up.
Maybe wrong it's been a while.

Maybe the rear blade thing above the exhausts is for the same legislation get-round?

Jobbo wrote: Thu Jun 20, 2024 11:26 am I have just seen this about the Cannonball Run car, as the film turns 45:

JINC

(The car - a '79 - turns 45, TCR came out in '81...but yeah, I know, typo ).

I have just become aware of this. I realise the wheels are intended to emulate the single seater, but this makes them look teeny. Worst QV wheels evah. Fact.

Not as cool as the Camel Trophy Land Rovers.

Fred Resurrection following the latest HarrysGarage video where he's been kicked in the head by a horse, and decides to re-fit the rear wing to his QV.

Jobbo correctly identifies his aesthetic folly

Jobbo wrote: Mon Mar 16, 2026 6:41 am Taking a drill to the Countach was a bit of a moment.

Still looks worse with the wing on.

But on top of this : I couldn't help but do some scribbling.....

The internet seems to agree that a wingless Countach (sporting styling conceived without any benefit of a wind tunnel) has a Cd=0.42. Which isn't great. Take this as a rough number, as I don't see any different numbers being quoted between original periscopo (lower with skinny wheels) vs later cars (higher, with fat wheels and pumped arches).


Assumptions:

1. The Countach QV has a 190mph top speed. (Fast Lane mag famously tested Pierluigi Martini's wingless QV at 195mph (2 way autostrada average using stopwatch and km markers), but also recognised that it theoretically meant the car was over the redline to achieve this. Unless it was experiencing some dragster-esque tyre growth at speed?)

2. The (stoopid) dealer-fit rear wing reduces the top speed by 15mph. So 175mph for a winged car. (Harry states 10mph in his vid, but I've seen 15 more consistently quoted).

3. Not an assumption, but a fact : power requirement varies with speed cubed, so if nothing else changes :




Drag Impact Of Wing
Using the above assumptions (and my possibly sketch fuzzy Monday morning head calculations) > on the agreement that nothing else changes : with the same power availabe, a top speed of 175mph would indicate an increase in drag coefficient to something like Cd=0.537. A drag increase of around 28%. Lucky Harry doesn't have to worry too much about fuel economy.

Even if we assume that Harry's 10mph speed loss is more accurate, you're still looking at an increase in drag coefficient to around Cd=0.494 (an increase of approx 17% over correct specification).



Brain state required to believe fitting the rear wing is a good idea
Stoopidy stoopid stoopids.


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Check my maths:

Mathematical Equation for power:
Power = 0.5 x air density x speed cubed x frontal area X Cd

If power = 455bhp, speed = 190mph, and Cd= 0.42, then we can calculate that the rest of the equation (ie 0.5 x air density x frontal area) = 0.00015794.

Check: 190*190*190*0.42*0.000157984 = 455. Lovely.

So applying the same constant, the same power, and 175mph, would require a Cd of 0.537.

It’s a pretty simple equation - everyone pretends they’re concerned with aerodynamics, top speeds and purity.

But the reality is, it looks cooler with the wing.

It looks cooler with both the front wing and rear wing in Cannonball Run, but just the rear wing in a barn in the Cotswolds? No, definitely cooler without.

Mik, I think the difference in top speed must be exaggerated - I don't think the wing can possibly alter the Cd that much. I agree with your maths.

I’ve always preferred the look with the wing but watching that video last night I just thought it looked a bit daft with it on, must have got used to seeing it without.