Nut question...how about a full carbon fiber gt40?

[I LOVE GT40- Paolo]

I sometimes ask myself...why nobody until today has ever thought to a full carbon fiber (monocoque and body) gt40?
I was really impressed by Alan yellow carbon fiber body geetee, but think nobody never did a monocoque in carbon fiber and a body too.
probably the cost will come really impressive..

Any idea of what can became the weight of such car?

paolo [img]/ubbthreads/images/graemlins/smoke.gif[/img]

[DavidTC]

Paolo
It would be perfectly possible BUT you are correct the cost of the materials alone would be prohibitive let alone the cost of composite moulds, labour etc. High quality co-continuous morpholgy toughened thermoset C-fibre prepreg as used in the construction of F1 monocoques would cost of the order of £ 80 per kilo ,approx 10 x the cost of stainless steel sheet. Of course the density is only about 1.6 compared with 7.9 for stainless so you would have a much lighter car. If you also made the car body of the same material you would have weight advantage over a standard glass fibre composite and again stifness advantages The specific stiffness of C fibre structures outperforms all metals by some 35 %, indeed most of the metals you would consider for a chssis/monocoque have somewhat similar specific modulus eg Aluminium,Titanium,Steel.
You would probably double the cost of the car and I am not sure the rest of the design is up to it.
Regards
David

[I LOVE GT40- Paolo]

yes, that is absolutely the main problem...but that's was just a crazy question...cause I am too interested in how lower will became the car (sure..exagerating in deside..althought with full carbon fiber car, also adding the most powerful engine for gt40 ,magnesium wheel..etc).

Maybe the car weight/power will come near to 1:1...and maybe that can also enter in a contest agaist Enzo and Koenissegg.
Looked from that point of view, also if a gt40 will be for 300.000usd,the car will remain cheaper than the ultimate supercars all around..


I know I am getting crazy...but think someday a real fool will try to do that [img]/ubbthreads/images/graemlins/grin.gif[/img]

Paolo [img]/ubbthreads/images/graemlins/dead_horse.gif[/img]

[Ron Earp]

Paolo,

If you goal is to beat a Enzo or Koenisegg then you need to do chassis/handling development. The horsepower is no problem and can be had relatively cheap, so you can eclipse those cars if you wish. All comes down to time and money. And I think you are right that someone will try and do it, if it is not already underway in many garages around the world...

Ron

[Bill Hough]

Why not just buy a recent LMP car chassis and mount a carbon-fiber GT40 body on it? I would love to do it, but the cost of the engineering would be a problem I bet. I wanted to build a fiberglass GT40 chassis back in 1965. I figured, if Jim Hall can make a fiberglass chassised Chaperral, so could I! I even wrote to Roy Lund of Ford Advanced Vehicles asking if I could buy a GT40 windshield and other parts to build my car. He referred to Shelby. Corporate "pass the buck"! I never built it, but who knows it could happen someday. Over the past year, the supply of carbon fiber has been in short supply here in the US. At first I though it was a trick to raise the price, but the price hasn't gone up much. The demand from the big aircraft manufacturers has taken a big bite out of the world's supply. Maybe someday carbon fiber will be plentiful and the supply will be priced low enough for an all GT40.

[DavidTC]

Guys
To add an air of realism to this debate; firstly its not just chassis design that would need development its also the drive train developments and you are then into something different altogether. Most of us like GT40's because they are basically simple cars. On the C fibre front there is lttle prospect of the price coming down unless new process technology becomes available to take cost out of the production chain. There are thoughts about how to do this BUT practical implication is a long way off. You also have the problem that the cost of the composite materials for the construction will always typically be 5x that of the C fibre itself (see the thread on F1).
It's all a 'pipe dream' I'm afraid.
David

[Ron Earp]

One interesting point is chassis development and tuning that can be done to make one car handle, or out handle, another - even with an inferior starting point.

The new Lotus Exige was recently at Road Atlanta with excellent SCCA drivers we compete against at the helm f the car wearing stickly R Hoosiers. Lap times were decent, around 1:45 or so after many adjustments were made, this with a 190hp car at around 2000 lbs. Mid-engine car, setup to hustle a track on a track day. Very good times for a mass produced sports car.

But when compared to our clapped out race cars it isn't too good.

Group 240z, BMW 325s, last gen 240sxs, and 2nd Gen RX7s all turn around 1:41s there with the same drivers, same tires, similar hp, but a little more weight (325 a lot more weight). And definitely inferior chassis design. Difference? Lots of time into chassis setup and getting the most out of what little is there since stock pieces had to be used, besides springs/shocks/bushings additional links, panhard bars where needed, etc.

Sure, the latter are caged cars and that is a huge improvement, but there are many folks I speak to regarding setup and changes and they would simply say "No way that 4 door pig will out perform the Exige on the road course". Well, it did and it is documented. Where there is a will many times there is a way.

Now, I'd like to have a "disposable" Exige to cage and use as a race car. Anyone have one they'd like to donate?

On the chassis front Lynn talked to Mosler here in the US and visited their facility where they make their CF tubs for their prototype cars. His aim was to talk with them about a CF chassis design and they entertained his concept and thoughts. I don't remember the complete details, he might have written it up on the forum, but as already mentioned it was expensive. But I don't remember it being insanely so (relatively speaking, it was insane for my needs and means). Maybe Lynn will chime in with details. I'm sure there are those around who would be willing to go there.

[Steve Kulper]

Hi All,
I have a friend who is a carbon fibre technician,(if that’s what you call them) he is currently tooling up for a CF chassis which he has offered to build one for me for a GT40.
It would need adapting and a lot of suspension mods, he said I would need to mount the engine off the rear bulk head and the rear suspension off the transaxle with inboard shocks, sounds expensive to me. The chassis would cost between $15- $17,000 Aussie dollars. He is currently building three bodies for a Le Manns team once finished he will finish off the chassis. The expected torsion stiffness will be around 27,000nm (if that is how you rate a chassis), the chassis will be built to comply with the LMP reg’s and rules for Le Mann, meaning it will have a driver tub/capsule similar to a F1 car. I have compared the length of his chassis between wheel centres and his will be 50mm or 2” longer than a GT40. If anyone wants me to ask him further technical questions let me know?

Steve

[Ian Anderson]

I do not consider this to be a "far out" idea

We had a visit t Ascari cars - organised through the GT40 clubs

This is their chassis for their road car!

More pictures if wanted

Ian

[DavidTC]

Ron
you have partly answered your own question. You mention the Lotus Exige; it has an excellent 'chassis' and can make best advantage on a circuit of its modest power/torque.The Enzo is very high tech and has plenty of 'trick' technology to put the prodigious output of the engine' to the road 'giving superb handling whether the car is on a track or normal road. In saying that it is easy and cheap to develop the power for a GT40 it is another to put it to best effect on a demanding circuit like the Nordschleife and the design would need to be a lot more sophisticated than a large hp engine and a slightly uprated suspension. Hence my previous comments.
It is interesting to note that in the era of 'simple' car designs (relatively 'floppy' chassis, no driver aids eg traction,launch control ABS, modest tyre performance etc etc) that the GT40 was viewed as a reaonable performer. In 1965 for example when Jim Clark in a Lotus won the German GP at the Nordschleife, his fastest lap was 8min 24secs, the sort of time a good sports car could go round in now. The Gt40 of McLaren and Hill in the same year had a fastest lap of around 9 minutes in the Nurburgring 1000km.
In the intervening period many of the kit car based replicas will have greatly improved the breed and it would be interesting to know what an updated GT40 record currently stands at. I suspect there will be an 'anorak' somewhere who can provide the answer!.
Although I greatly approve of the attempts to improve the breed with straightfoward engineering ,if you have to incorporate a great many driver aids inlcuding lightning fast paddle gear shifts then you are moving many steps to far from the original for my taste.
Regards
David

[Howard Jones]

The reason a Enzo costs so much is all the limited production parts including the car itself.

The reason they are fast isn't so hard to imagine or achieve.

If the idea is to equal and then better the lap times of an Enzo in one of our GT40s then the path is clear. More, power and grip and less weight. I will assume the same driver for our "test"

Lets see, Enzo about 3200 pounds, 600HP and big modern Z rated supercar tires.

OK build a GT40 down to 2000 pounds, put in 600HP and the same size tires and with a good engineer and driver, a few days of track test time, and about 1/3 the money, Bingo Enzo in the rearview mirror!

I think with a budget of $150K-170K, this includes the track sessions and some budget for professional advice and help, one of us could absolutely KILL Enzo's.

[DavidTC]

Ok, but to what purpose ?; and lets say its a circuit where the Enzo can approach terminal velocity at least once per circuit, say Le Castallet with the old bottom loop open. I don't see anything but the GT40 flying into the gravel trap on the fast right hander at the end of the straight whereas the Enzo's aerodynamic downforce and carbon -ceramic brakes would make this a doddle. I have seen stock Ferrari 550's reach 180mph at the end of the straight so the Enzo would have no problem reaching terminal velocity. On another tack its a pity the French GP is not at Paul Ricard; it is much more interesting as a circuit than the anodyne Magny Cours and its also in a nice part of France. The long circuit was of course abandoned after Elio de Angelis' accident but the shorter circuit is still interesting. Maybe Bernie will shift the venue before he retires; he owns the circuit.
David

[Andy Besic]

I agree with David.

Our GT40's can be developed with modern technology "under the skin" to a point that they will outperform the original race cars. With MAJOR aerodynamic changes, chassis/suspension changes will they truly be able to beat the Enzo in most scenario's. If these major changes take place can you call it a GT40 anymore?

Howard
I have found the most terrifying thing in my car on the track is a "kink" or mild bend at the end of a straight that has you near 140mph. If I lift, the car becomes unsettled, If I stay on it, the kink is no problem but I can't slow enough for the following turn, If I had downforce and traction control, I wouldn't have to change my pants at the end. [img]/ubbthreads/images/graemlins/blush.gif[/img]

[I LOVE GT40- Paolo]

eheh, I agree basically with DTC Pilot.
Dunno honestly if will be so easy to beat a chassis design as the 2004 Ferrari Enzo.We are even talking of one of the very best top car ever done by human beings, developed with 20th century technology,by the best top car factory all over the world(specialized ONLY in supercars..)
Guess if someone really will have to kill the Enzo,he probably will redraw at all the chassis design of all the geetees we have seen until today(and probably a LM serie prototype will born),also updating at least gear shifter and brakes..trying to be nearer modern vehicles performances.
And if we plan to make a prototype contest the target will come not the enzo..but the stratospheric FXX.....
Also there maybe the costs will increase too much (also I adore the gt40 cause basically not to expensive as a top car,even if replica).
But..mean my nut question as a pure tech engeneer exercise, think surely many many of u all think at this full carbon fiber idea.
Just to see (in phantasy unless someone really will try to do that..) if the real ULTIMATE ford gt40 can be again the best car of the world.

Paolo

[Mike Dozier]

I seem to recall a thread
a few years back about someone in Germany (?) who
had built a "modernized" carbon fiber GT40...I can even
recall seeing the pictures....unfortunately my Forum search
skills are pathetic.

MikeD

[DavidTC]

Gentlemen
We seem to have come full circle. The concept is fine and is do-able at a price BUT why would you bother. The updated versions are already pretty entertaining and visons of an Enzo beater are misplaced. Enjoy the GT40 for what it is; a classic design with a big american lump that goes like st--.
Regards
David
ps BUT is a handful compared with more 'modern' designs; part of the charm really !.

[Howard Jones]

Oh hell we can always put on some big damn wings, dam up the front, and add more power to push it. With enough power and large enough wings all things can be done.

You guys are right though... It won't be a GT40 anymore. Or at least not a pretty one.

And.... there's no "purpose" in any of this. Just a bunch of the boys bench racin sport cars.

[Andy Besic]

It's -9F in Chicago this morning....bench racing is all I have today!

[Howard Jones]

Andy, It's pretty hard to get a ticket sitting at the computer with your eyes closed and your mind at about 140.

But then that's half of the fun! Isn't it?

Back to the original topic. I wonder what the total weight savings would be with a carbon chassis and body over let's say a current RF chassis with fiberglass body. No other differences. Could it be as much as 500 pounds? That's a lot of weight. I kinda doubt it. But then I don't know much about this stuff. I would guess that the real value would be in increased chassis stiffness. In race cars this is the most important thing a chassis does. For street/ light track work I don't think the difference would be appreciated.

I don't think the costs are really justified unless the end user is serious about winning races. Real races for money.

[Andy Besic]

500lbs would make it the ultimate parking lot racer! Stiff and light will help our cars excel vs modern cars until the speeds increase to the point that modern aerodynamics becomes a huge factor.