Downforce

[kenprotheroe]

Coming from Noble(s) & taking delivery of a CSR 260 on Saturday, I have noted on the Gassing Station, the apparent lack of downforce on Caterhams.

My question being, surely that could be added to by fixing an adjustable blade off the top of the
track-day roll-bar. Has anyone attempted this, or is the projected height of such a negative factor ?

[ewenm]

My first question would be why? The top speeds of 7s are not that high and the grip levels are excellent due to the low centre of gravity and proportionally wide stance (especially in a CSR).

Edit: as for doing it, Caterham did have a front chin spoiler on a car but no rear one and declared that it made the car far too pointy - I did wonder then why they didn't just add a rear spoiler as well to see what the effect was.

Edited by ewenm on Thursday 5th July 17:26

[Matt W]

I have seen a green R500 with front and rear wings on it at Donington Park and saw it for sale in a magazine not so long ago. I'll see if I can find an online advert later.

[smrc426]

If you want wings and slicks, go for a Mallock. Adrian Reynard said they are the best handling and quickest 7-esque cars out there. The Caterham and all its different itterations are aerodynamically flawd.

[ewenm]

I reckon a re-shaping of the rear wings on the CSR (similar to the front ones) would be the first place to start.

[mchammer89]

Here's a company who make rear diffusers for Caterhams http://www.reverie.ltd.uk/en/gallery/reardiffusers...

[Murph7355]

kenprotheroe said:

Coming from Noble(s) & taking delivery of a CSR 260 on Saturday, I have noted on the Gassing Station, the apparent lack of downforce on Caterhams.

My question being, surely that could be added to by fixing an adjustable blade off the top of the
track-day roll-bar. Has anyone attempted this, or is the projected height of such a negative factor ?

You need to readjust...

The 7 is not about aero, it's about pure, raw, unadulterated handling.

Get it flat floored (with you in it - cars are badly set up out of the factory typically, unless you love understeer) and spend some time learning to get the most out of it. You will almost certainly find it's plenty quick enough round corners to avoid slapping tea trays on it.

[smrc426]

mchammer89 said:

Here's a company who make rear diffusers for Caterhams http://www.reverie.ltd.uk/en/gallery/reardiffusers...

Why buy a diffuser when the rest of the aero is poo?

[dannylt]

Right! Compared to something designed with downforce in mind there is no comparison. It's fun, as opposed to very very fast.

[mchammer89]

smrc426 said:

mchammer89 said:

Here's a company who make rear diffusers for Caterhams http://www.reverie.ltd.uk/en/gallery/reardiffusers...

Why buy a diffuser when the rest of the aero is poo?

To be honest I would mainly get one to reduce the drag, not improve downforce, i've read somewhere that a Caterham has a drag co-effificient of around 0.7, kinda like a brick with wheels, every little helps.

[Pugsey]

Murph7355 said:

kenprotheroe said:

Coming from Noble(s) & taking delivery of a CSR 260 on Saturday, I have noted on the Gassing Station, the apparent lack of downforce on Caterhams.

My question being, surely that could be added to by fixing an adjustable blade off the top of the
track-day roll-bar. Has anyone attempted this, or is the projected height of such a negative factor ?

You need to readjust...

The 7 is not about aero, it's about pure, raw, unadulterated handling.

Get it flat floored (with you in it - cars are badly set up out of the factory typically, unless you love understeer) and spend some time learning to get the most out of it. You will almost certainly find it's plenty quick enough round corners to avoid slapping tea trays on it.

Murph - Good advice. My new R400 arrives next week and I'm going to get a few miles on it in month one 'as is' and then need to get it set up. I'm a bit out of touch with all things Caterham really - any suggestions who to go to?

[Noger]

mchammer89 said:

smrc426 said:

mchammer89 said:

Here's a company who make rear diffusers for Caterhams http://www.reverie.ltd.uk/en/gallery/reardiffusers...

Why buy a diffuser when the rest of the aero is poo?

To be honest I would mainly get one to reduce the drag, not improve downforce, i've read somewhere that a Caterham has a drag co-effificient of around 0.7, kinda like a brick with wheels, every little helps.

A brick is about 2.0, for reference

But you are right, the Cd for a Seven is pretty poor, but there is not much of it, hence the CdA is actually pretty good. IIRC the Elise comes in a gnats under 0.6m^2, a Seven is about 0.63ish. One was designed in a wind tunnel, the other in a shed. Not much difference, and ultimately real world results tell us the same thing, similary powered 7 and Elise have about the same tops speeds.

Edited by Noger on Friday 6th July 13:23

[delivery dave]

smrc426 said:

mchammer89 said:

Here's a company who make rear diffusers for Caterhams http://www.reverie.ltd.uk/en/gallery/reardiffusers...

Why buy a diffuser when the rest of the aero is poo?

smrc426 also said "I am a Mercedes fanatic, actually I am a Mercedes obsessive. I have a 98' A-Class"

[smrc426]

delivery dave said:

smrc426 said:

mchammer89 said:

Here's a company who make rear diffusers for Caterhams http://www.reverie.ltd.uk/en/gallery/reardiffusers...

Why buy a diffuser when the rest of the aero is poo?

smrc426 also said "I am a Mercedes fanatic, actually I am a Mercedes obsessive. I have a 98' A-Class"

I believe the aero on the A-class is actually quite good. The A-class is a daily runabout, I have another car that has splitters and wings for racing. I'll be developing more aero devices when the car is fully restored. I have aerodynamics experience from university.

[mchammer89]

Okay, not a Caterham, but it's a Seven type car
http://pistonheads.com/sales/198520.htm
Quite a large chin-spoiler and rear diffuser, pretty odd looking.

[rubystone]

smrc426 said:

mchammer89 said:

Here's a company who make rear diffusers for Caterhams http://www.reverie.ltd.uk/en/gallery/reardiffusers...

Why buy a diffuser when the rest of the aero is poo?

...the diffuser does no more than keep the de-dion nice and clean

aero on a Caterham? How about R500 aero wishbones - £700 each aren't they?