Aerodynamic Experts advice needed

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daxtojeiro
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Aerodynamic Experts advice needed

Post by daxtojeiro »

Hi all,
I've been looking into some form of splitter/spoiler for the front of my Cobra. Im no expert at this , but a lot of te TVR guys add a spoiler under the car, but from what Ive read this lifts the car up, which isnt good in my mind!
I've read that a splitter is what I need to add some front end downforce. So this is what Ive come up with, anyone see any issues with it, before I fit it :)
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http://www.extraefi.co.uk/cobra/accobra.htm SuperCharged 5325cc V8 Cobra Replica (Full sequential Fuel and Ignition MS3 management)

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Darkspeed
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Post by Darkspeed »

I would not call that a splitter - its more of an undertray - And I doubt that what you have there will make any significant difference.

First you need to establish what pressure area you have above the bonnet - if you pop the catch and drive over 60 with it what does the bonnet do?

A front splitter generally works with a dam first to push the air around rather than under the car - then a splitter is there to provide the point at which the air is "split" to go under or around the car - to be effective the splitter normally extends to behind the front axle line.

I can see where you are going with the flaps but to be effective to have to throw up a volume of weight of air which will give you an equivelent down force - Newtons law and all that - for every action.... If you throw up a ton of air you get a ton of downforce. I cannot bsee that you are going to throw that air airwhere but into the body of the car - they would be better to push the air sideways into the low pressure area behind the front wheels.

Andrew
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ian.stewart
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Post by ian.stewart »

I keep looking at that numberplate. hinge it at the bottom, use a low load gas strut, to keep it upright at low speed, bit faster airpressure pushes the plate back at a predetermined angle, which should add downforce,
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daxtojeiro
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Post by daxtojeiro »

OK, thanks for that, I dont really want to add anything to the front. I thought this would be a discreate method, but now Ive read your explanation I can see it isnt going to do anything :(
It was going to be an undertray to start with, but I got carried away. I will cut the wings off it and turn it into a tray.

The number plate is a good point, I may ba able to do something with that. Oter guys add a metal plate where that number plate is, I personally dont like them, but could do something with what I have,
thanks
Phil
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http://www.extraefi.co.uk/cobra/accobra.htm SuperCharged 5325cc V8 Cobra Replica (Full sequential Fuel and Ignition MS3 management)

stevieturbo
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Post by stevieturbo »

I think you're missing the point of what a splitter is supposed to do ?

The idea is to prevent any air at all passing under the vehicle.

Adding things that potentially makes airflow under the car easier, will increase lift. Not decrease it.

Although unless you're hitting circa 100+ and then some, I dont think it will make a huge difference
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Ian Anderson
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Post by Ian Anderson »

Canards (small wings) on the outside of the body will do more
Positioned on front of front wheels at anything up to 45 degrees will add downforce

Ian
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Post by kiwicar »

For My 2p, I think you will get an improvment in stability from the undertray thing you have made, it will not funtion as a splitter but will make the flow under the car and into the wheel wells behave seperatly and be less turbulant which will be a good thing. I would angle the front edge at the sides down not up as this will improve flow around the brakes. I would also attempt to close the gap between your new plate and the bottom of the radiator. Appart from what you have some sort of air dam that stopps air going under the car and direct it to the sides would help reduce front lift, a splitter below this would also help, but I think look silly.
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