rear gernay flap

[scarei]

Does any one no if u can get a rear gernay flap for the boot, was thinking about getting one,but if i carnt get hold of one may go with the evo style spoiler,but I have hard a lot of people favoring the f2 spoiler,just have not seen a rear gernay flap on a puma?

 

[martinthrapston]

am i right in thinking you want a rear spoiler,have a look through the gallery theres some cars in there with different types fitted

 

[ScubaSteve]

Gurney flap

 

[lusid666]

[youtube]http://www.youtube.com/watch?v=TK8-VuwPqq4[/youtube]

 

[Sjoerd]

I have one actually I got it from a german friend: http://www.tuninghaus.de" onclick="window.open(this.href);return false;
Later I made a simulation on the effects of it on the Puma:
http://www.youtube.com/watch?v=-3Nh-_LAtmk" onclick="window.open(this.href);return false;
http://www.youtube.com/watch?v=7MDFLCf9Zro" onclick="window.open(this.href);return false;

It's increasing the downforce a bit when you reach speeds of about 250km/h. The back end can get twitchy then, which this stabilises. You see in the videos a cleaner airflow, with about the same drag but more downforce, cos it's actually 'cleaning' the air. It makes sure really the dirty air behind the car gets a little bit cleaner and is put to use. Works a treat for me

 

[scarei]

I no what a real gernay flap is, I want to no were I can get one from,what do people think about the evo style spoiler and the f2 spoiler I Like the evo style one but hard a lot of people say the f2 is better

 

[ScubaSteve]

Iv already corrected your spelling once ffs. Anyway to answer your question I think the EVO spoiler is a worthless piece of shit. Just adds weight looks crap and does nothing. The f2 is functional though I think only frp or wide arched ones really pull it off

 

[The Arch Bishop]

'Iv' Steve? I think you mean 'I've'.

 

[scarei]

I can spell chose not to but ok f2 it is,what about a rear gurnay flap

 

[Sjoerd]

I can spell chose not to but ok f2 it is,what about a rear gurnay flap

See my above post with calculations/simulations and a actual link where to buy one which has been made especially for the Puma by one of the designers of the damn car. Is it really that hard man? :wink:


http://www.tuninghaus.de/shop/product_info.php?cPath=1624_75_111_1313_1331_1590&products_id=19940" onclick="window.open(this.href);return false;

It looks like this (I know the picture sucks, but i can't walk out now because its dark):

http://a7.sphotos.ak.fbcdn.net/hphotos-ak-snc7/325949_2457088107733_468630648_o.jpg" onclick="window.open(this.href);return false;

Anyway I wouldn't get any spoiler, from a technical point of view. A small gurney flap can pull off the trick just as well without ruining the looks and creating more drag to the car. There is no need for much extra downforce at the back as it only becomes instable around 250km/h (150mph in your false british system) which most Puma's will never get to anyway.

 

[scarei]

Tried going on the website says item not found,was not looking at going 150 mph tbh I want one for looks and for a gernay flap would look good like it does on urs but Yh days item nit found on that page mate

 

[spike.]

If you want one for looks, then is no point aking what others think... Get one YOU like, as its your car, and it shouldn't matter what others think.

Sjoerd has been more than helpful, in giving a technical answer, as to why some spoilers are just for looks, and not for function.

Its only polite to spell things correctly, choosing to misspell something, when you know its incorrect, just shows you as ignorant. IMO

 

[Flying Scotsman]

I have Evo spoilers and F2, The Evo does have a place as it was designed for the S1600 Series, however, ScubaSteve is right, there is more weight behind it than an F2 but not much really, besides, downforce is what you're after. Evo's are easy to come by, F2's are not.
Forget the Gurney Flap... unless youre doing something that you really need to shave milliseconds off... and if you got an F2, i wouldnt mess with it...

And ScubaSteve.... only FRP's or Widies pull off the F2.... I take offence!

 

[ScubaSteve]

I think its a bit big for standard ones, yours has 17s and a few other body bits so probs doesn't stand out quite so much

 

[Flying Scotsman]

I think its a bit big for standard ones, yours has 17s and a few other body bits so probs doesn't stand out quite so much

Yeah, I bought the Evo's because the F2 didn't stand out enough lol. But I love the shape and style of the F2... a very unique rear wing.

 

[evilrob]

I had a Gurney fap once, if that helps...

Hmck... frgh... *fapfapfapfap* huwrgh... *fapfapfap*

 

[warrenpenalver]

The evo spoiler was a ford motorsport product and was never fitted to any of the works cars, nor was it a standard part on the kit cars either.

I have one actually I got it from a german friend: http://www.tuninghaus.de" onclick="window.open(this.href);return false;
Later I made a simulation on the effects of it on the Puma:
http://www.youtube.com/watch?v=-3Nh-_LAtmk" onclick="window.open(this.href);return false;
http://www.youtube.com/watch?v=7MDFLCf9Zro" onclick="window.open(this.href);return false;

How accurate is that software simulation? Also can it display a better resolution?

The simulation videos show boundary layer seperation on the roof line which seems quite high for such a curved car shape. It also seems to imply that fords decision that the original designed curved boot was too slippery hence the angular spoiler might have been based on low levels of air flow over it.

As shown the airflow in those areas are all vortices so a normal spoiler would not have significant flow over it, nor generate significant downforce. Same goes with a gurney flap.

Sure you can see cleaned up vortices.

Maybe its the simulation but i would have expected the boundary layer to seperate much later.

It just seems odd that boreham went to so much effort with tunnel testing of the F2 spoiler yet put it in turbulent airflow rather than in cleaner air flow for better efficiency.

 

[warrenpenalver]

Couple of pics to show what i mean:

Even this boxy merc, the air flow only partially seperates on the roof line rear edge and some flow still is forced down over the rear screen.

A slightly more curvy saloon car:

This merc coupe thingy is closer in shape to the puma:

And a mad car:

You can clearly see the spoilers effect on the back of that zonda.

And a shit box hatch back:

 

[PumaNoob]

Ive been trying to find wind tunnel pics of a puma for ages, i really want to see what affect the F2 spoiler has on acceleration and at what speed it really starts to make a difference.

 

[Sjoerd]

Well honestly it was a attempt to get to know CFD a bit after I got quite inspired with a subject in Uni. It's not perfect, nor is the model I designed itself. Anyway one of the original engineers once said it was far from perfect but was a good indication..
I am trying to complete a full CAD model of the Puma for the last 2 years. I guess I have about 60% of the parts now, down to the millimeter correct The body is a pain in the ass though to design. Only once I got it perfect i'm going to put it in the programme again. I might have a Faro-arm to measure it in the near future. That'd be a pretty good way to get the design done well

I used Algor to simulate it by the way.

I've been thinking about using the scale model I have at the moment and build some kind of mini- wind tunnel. The results are offcourse scaleable to full size vehicles. Should be fun to design and build

Ow and scarei, use the link I posted in Internet Explorer. For some strange reason the website doesn't work in Chrome/Firefox/whatever..

Ps: it'd help if you'd use proper english. For a not native speaker it's a bit hard to understand at times. The bigger the accent or slang, the worse it is for us :wink: