Carbon fiber panels / radiator water spray?

[Igor+]

Isn’t it better to use carbon fiber panels instead of alloy ones to make Ultima chassis stiffer?

Is it possible to spray some water to radiator to cool it at idle?
Aquamist is one of manufacturers of spraying stuff.

[US-GTR]

I don't think that it is an issue of the radiator not cooling well enough, I think the water pump is not flowing enough water to allow the radiator to cool it. IMHO...

As far as composit paneling... Composits can endure vibration, and can be quite stiff. However composits(thin sheets) cannot survive the impact of road debris and the large amount of vibration that the engine and road will creat throughout the chassis. They may last for a short time, but over time the panels will begin to delaminate and show stress. Aluminum is better at surviving these conditions and at a lower cost.

(I understand that composits can be designed to overcome these conditions, but the cost/advantage would be overwelming)

>> Edited by US-GTR on Monday 16th June 00:51

[jhr8]

If you're interested in carbon-fiber, contact the factory. I just saw one that the factory built, in carbon-fiber (and instead of the factory, you may wanna try this, cuz it's NOT selling for a much higher price than regular Ultimas): I think it's in the "for sale" section of ultimaclub.com .

[james]

I think he's talking about the panelling that is normally done in aluminium, rather than the whole body shell. I don't think that the carbon fibre bodied car was particularly light, as you usually end up having to do a lot of work to it to get paint to stick. By the time it's painted, it isn't much lighter than the lightweight GRP gelcoated shells that they make.

[Igor+]

Sure, I mean paneling but not the body.
And the reason is not to make the car lighter but to make the chassis stiffer.

[jhr8]

I think he's talking about the panelling that is normally done in aluminium, rather than the whole body shell.

Yeah, I know; it's just that I was just working from memory (and memory about a car I didn't take much interest in, cuz I also think that carbon-fiber isn't worth its cost...unless you're doing pro-racing with big purses and then every last pound counts...). i.e., it was 'which parts of the one for sale are carbon-fiber' that I got wrong, not Igor's parts which he wants made of carbon.

I don't think that the carbon fibre bodied car was particularly light, as you usually end up having to do a lot of work to it to get paint to stick.

I think the coolest idea for carbon-fiber is to leave it unpainted. Of course, I'd never do that for a street-car, cuz then it becomes a theft-magnet. :-)

Well, Igor, can't you just not order the alloy skins, and provide your own custom-sized carbon-fiber panels instead? I'd have to say that if you do, you should cover their sides exposed to wear: Although strong, in addition to the faults US-GTR mentioned, carbon wears much quicker than most metals.

>> Edited by jhr8 on Monday 16th June 15:26

[james]

If you want to improve stiffness, the most practical material to use is aluminium honeycomb. It's very rigid, and very light. The only problem may be its thickness, as the Ultima is designed to use thin ally sheet. You would probably need to bond it in order to gain maximum stiffness too.

Probably more trouble than its worth, as you could much more easily increase the stiffness of the chasis by adding a few well placed cross braces.

But if it's only going to be a road car, the standard chasis is more than stiff enough anyway.

James

[Igor+]

Actually I decided to use alloy honeycombs.

[PiB]

Does the factory provide the option of alloy, carbon fiber or honey comb Al panels? Or are the carbon and honeycomb panels an aftermarket custom self design deal?

[jay esterer]

look at www.ultimav12.ca for measurments and improvements of frame stiffness on the GTR.
you may be interested to see the relativly small improvement from clading the sides of the frame.
the softest part of the GTR is the engine bay and above the drivers feet and head.
hope this is useful info

[Igor+]

I’m not the expert, but I think that ultimav12 destroyed distribution of forces and torques calculated by manufacturer.
Perhaps it’s good, perhaps it’s bad.

[doc_fudge]

Jay may have altered the crumple zones slightly, but it appears that he has also stiffened the "passenger cell" and that can only be good...right?

I think that Jay has also increased the "passive" safety of the car... after all if the suspension has a stiffer chassis to work off, it can do its job more effectively and hence contribute to avoiding an accident in the first place.

Over here in Australia, some automotive engineers insist on a chassis torsion test before an Individually constructed vehicle can be registered. If your chassis doesnt measure up, either stiffen it up or take it home because you wont be allowed out to play.(I can just imagine the conotations James is thinking of for that last sentence...Sorry James!)

Andy

[Igor+]

Why does manufacturer warn against paneling under engine area?
The chassis becomes stiffer.
Perhaps, manufacturer knows better everything about this chassis!

[james]

They used to panel under the engine area, but it restricted air flow, which caused cooling problems. They removed the panelling, and the cooling problem went away.

The whole of my Mk4 Sport is panelled out underneath, but I had quite a few issues with cooling (but then I was racing, so the heat tends to build up somewhat more than on the road). I solved the problems in the end, but it took a lot of work.