So that rear spoiler is useful afterall

[Sinturion]

Here's a very neat video of aerodynamic flow testing of a few cars:
https://www.youtube.com/watch?v=quDLzxmJl5I" onclick="window.open(this.href);return false;

Skip through to 13.50 to see the AW11.

[Ash Kelly Barr]

This is awesome! Now I know why the top of my rear bumper is always dusty

[Millhouse1]

Haha yeah same. Every time after a drive, the top of the rear bumper has a dirty film on it. Always wondered why!

[Ash Kelly Barr]

.

[Sinturion]

I was thinking about something like that.

Though if you wanted the most out of it, you'd need to extend it over the boot lid to get a softer angle.

[Ash Kelly Barr]

Kinda like this?

[Barark]

Looks like an FC RX7 now

[Ash Kelly Barr]

Haha I know! Kinda looks like something an 80's Japanese night rider would drive haha

[mickeyduck]

Interesting video Alex.

As I suspected the OEM wing helps to stabilise the separation bubble over the engine lid, and this reduces the angle of separation of the upper air flow.

angle no wing.png (392.91 KiB) Viewed 2253 times

angle with wing.png (324.36 KiB) Viewed 2253 times

As you may have noticed, without the wing the separation bubble over the engine lid is a bit unstable, with the rear end of it hitting the boot lid about half way back on the boot and bouncing air back up. (watch the video over a few times if you need to folks). Interesting that the front edge of the OEM wing was designed to be just ahead of that point to help stabilise the separation bubble. As well as lift the lower (bumper) bubble up. Combine the two things and you have less drag because the aerofoil aspect ratio is lengthened - if you think of the car as leaving a teardrop shaped hole in the air. Longer teardrop (or longer and thinner aerofoil) = less drag. The separation bubbles help create that longer aerofoil as long as they are kept stable. And that rear OEM wing helps add that stability to them, as seen in the video.

separation bbl no wing 2.png (172.35 KiB) Viewed 2253 times

longer separation bbl.png (170.12 KiB) Viewed 2253 times

I also find it interesting that this video confirms my wool tell-tale test result that says a rear wing needs to be at least 15cm above the boot lid at 100kmh if it is to generate any down-force. Look at the height of the fast moving air relative to the boot lid, you'll see that a rear wing needs to be at least 15, preferably 20cm up there to catch that faster moving air.

wing effective height.png (338.38 KiB) Viewed 2253 times

And yes the SW is clearly a slicker beast aerodynamically. One glance at it tells you as much. Driving one with the windows down simply screams that at you.

Damn shame the SW is such a whale by comparison then when it comes to weight and the ability to chuck it around corners. Slim an SW down to AW weight if you can (or massively increase its power and tyre area) and then things start to come right...

Cool vid mate.

[Sinturion]

Kinda like this?

Further.. Probably all the way to the edge. It would look rather odd though

[Barark]

If only charlie had an Aw11 spoiler that perfectly caught this streamline

[Ash Kelly Barr]

Yeah it's not really and MR2 anymore when you start going to thouse extremes haha

On anouther note, I have anouther boot lid I want to put a big ass wing on and swop lids for when I hit the track
I'm wondering if I made a small duckbill lip along the edge and then planted a big GT wing 200mm above that
Make the duckbill a bit more flat and stick back like a drag spolier the have the GT wing only 200mm above that.
Duckbill to stabilise air at the rear
And GT wing right in the highish pressure zone?
If done well could look kinda bad ass to

Edit: look up the old 86 series in jap and some of them run the TRD one with a GT wing

[mickeyduck]

Yeah I reckon a fairly upright spoiler maybe 100mm tall to help stabilise the separation bubbles, with a wing mounted about 200mm above the boot would be a go for sure Ash. If they did it years ago for racing then I can see why.

I'm thinking of making a heavy perspex spoiler similar to that on a TVR.

And to you too Viv...! With your nice after market wing that John forgot to sell me... LOL