Carbon driveshafts and prop shaft?

[tartan_rob]

Anyone done this or know where they can be purchased? For any Audi, B5 S4/RS4, B6, B7 C6 etc etc

I am on a CF course next week and half toying with the idea of having a go at a CF prop shaft to replace the std one as it weighs the same as house.

Ideas/thoughts?

[rikrose]

Sounds interesting. I've seen them in projects in the US, but never over here. I'm wondering what thickness you need, and whether it'll take the big torque in, say an MRC500 car. what sort of gain do you get from it, and are there bigger, cheaper wins around? Is this just "every little helps"?

[BRETTCOLLINS]

like the idea, would be up for trying it..

[Andiroo]

We've already investigated this for my 'work in progress' Brett, few options open to us, will let you know how we get on, what torque they can take, is it cost effective etc etc

Cheers,

Andiroo

[BRETTCOLLINS]

COOL, let me know, All for dragging back as much transmission loss back as possible.

[rikrose]

Seconded. We're at 25% on the B5 S4, aren't we? Or was it 33%? I'm all for lightening the spininng load. I suspect that the next time this engine gets pulled, it's going to have some proportion of the "lightened" stuff put on, too.

[tartan_rob]

I am keen to make as many components carbon as possible. Why does the intake manifold have to be cast alloy?

So will be going for shafts, bonnet, wings and boot first.

[DavidT]

You're gonna do that to your B7 RS4 Rob ?

[JonnyX]

Seconded. We're at 25% on the B5 S4, aren't we? Or was it 33%? I'm all for lightening the spininng load. I suspect that the next time this engine gets pulled, it's going to have some proportion of the "lightened" stuff put on, too.

I've never understood this. Surely the transmission loss (if the rotating components are
unchanged) is an absolute figure give or take, not a percentage.

For instance, does a car with 300bhp and 33% losses (i.e. 200atw) lose an additional
100bhp through the same rotating components if upgraded to 600bhp? I don't really
think so.

It may increase slightly (due to additional stresses and hysteresis losson driveline
components) but it's surely not a linear relationship which a percentage implies.

[pistonart]

Not sure you could make a carbon prop in the conventianal way of laying up carbon sheet. It would have jionts, weak spots, and would probably be very think o compensate. Props are usually spun so a continuos weave is achieved. Thick ness and strenght is all calculated for max weight saving and strenght.

I have had carbon products made before and if enough interest (would need a batch of ten) can get them made. Approx cost £1200 each. Would need a prop to work off of and max torque figures so as not to have it built to weak.

[jeffw]

It is not logical for the transmission loses to be a percentage. A certain set-up of transmission components will always have the same losses regardless of the power the engine puts out. There may be a slight increase in engine losses as power increases but this is not going to be proportional. This is always my arguement with RR figures.

[Andiroo]

Carbon props and driveshats aside for the moment, Jonny & Jeff make a good point, something I've pondered for a long time. Unfortunately, even after 8 years of trying to find the answer it somewhat bemuses me that no-one can tell me ........

Back to the props, @ pistonart, yes mate it is a different way of laying the carbon than a normal pre-preg lay - we used the same technique for the exhaust cans for Honda Fireblades back in the '90's but a lot lower tech. You would be quite surprised as to how much torque these things can take when they're built correctly

Cheers,

Andiroo

[tartan_rob]

David - I'm not sure where to start but am on a course next week and I'll have a better understanding then. My mate that I'm going with is going to start making Jetski parts. That will prove a good test bed for bigger projects/surfaces.

RE Prop shafts etc, I would simply try and find a way of binding the end joints onto Carbon poles. I'm not sure if they will take it but no harm in trying and if I can get it to work then there is scope for Driveshafts and other rotating bits.

[viperbl]

My mate got carbon prop shaft for his caterham from here and I am very sure he would be able to help with a custom part as well ...

Lol, my friend said it looked a lovely the part, such a shame to stick it where it could not be seen! but his mrs was against the idea of putting it on the mantelpiece ...

[pistonart]

Same manufacturer we use.

Main advantages of the props are it is lighter, so any weight saving is good. It saves on intertia, so is easier to spin, car barakes better, accelerates better, more responsive.
Big hp cars are less likely to snap shafts as carbon will flex, so is gentler on diffs and gear boxes.