43 replies to this topic

[Winstar]

so a 7-12 degree diffuser clearing the rear by 5cm will work just fine. If anything, having it sat 2cm below the clam at the rear (like Max) to clear the exhaust "hump" will improve cooling and reduce the angle.

I like your idea of a small extension to the roof slope maybe with a couple of VG's attached to it. Should be easy to get a 10cm wide piece of transparent perspex to extend the roof and fix on either side, stick on the VG's, attach a few small ribbons to the engine cover etc and check improvements in flow at different speeds (right now water droplest don't even move off the engine cover/ rear spoiler)

if your going to drop the angle like MAXR then Ideally you should/can get rid of the small center channel and alter the number of vanes to change the diffusion, there's also some good ideas for other things like extensions under the wishbones stopping flow creating lift on the Revire Exige wind tunnel tests. Edit click pdf

Repalceing the rollover hoop cover with somthing more aerodynamic could also be an oportunity to save some weight you wouldn't belive how heavy it is.

Edited by Winstar, 20 May 2008 - 09:05 AM.

[subseamac]

couldn't agree more.

Ideally we could find somebody on here with access to a car lift or pit, and spend some time measuring up under the car to have a bespoke diffuser made up. I don't have facilities to do that myself

p.s there is one that gets close (see http://www.carspezials.de/ under karosserie) but it doesn't seem to stick out enough and I'm not sure about the way the vertical vanes are spaced. I'm thinking about something like that that does stick out 5cm to clear the exhaust tips and with the vertical vanes evenly spaced. the two attachment points look quite neat maybe they can be used to alter the angle etc if needed.

Edited by subseamac, 20 May 2008 - 10:04 AM.

[Stu-7]

I have to admit that I agree with dw1 on this one. I was out at the 'Ring a few weeks ago and through Schwedenkreuz at 125mph, the car felt really planted. This was very different to how another VX I went out in last October felt in the same place. Probably no down-force being created, but certainly helping to eliminate some of the lift and twitchiness at high speeds. Plus they look great, and that counts for a lot in my book

There you go again....talking about my erratic driving style....

[alanoo]

there's also some good ideas for other things like extensions under the wishbones stopping flow creating lift on the Revire Exige wind tunnel tests. Edit click pdf

Funny, I did not knew about the Reverie wind tunnel study, but a few weeks ago we got an aero eng mate to look 5 minutes at the Speedster and he said immediately how bad the standard diffuser is and the very simple things should be extending it in the back and extend outer vanes

Edited by alanoo, 21 May 2008 - 08:20 PM.