I have a replica builder who claim that they build a Carbon Fiber body - does anybody know about any others - or of a place who build just the body?
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I've been bit pretty hard in the past by a builder who said he could do many, many things which were just vaporware. I'd be very leery and very careful. Claiming to be able to do something is vastly different than being able to actually do it.
Start by asking to see in person examples of existing CF bodies the builder has completed. I'm guessing there will be crickets.
He's in Denmark. I think there is a whole lot more going on in Europe with these more modern techniques. Bet the Alpha Romeo is least expensive car manf using a large amount of carbon fiber. I've seen articles on using 3D printers to produce carbon fiber car parts (good YouTube on building a CF Miata hardtop).
In US, a larger displacement engine is cheaper than weight saving for performance. US Gas is cheap too. There are no government restrictive taxes on engine displacement or horsepower (save the gas guzzler tax). In Europe, above 1600 cc there is an added tax of 45-145%. For example, in US all new Miatas are 2.0L - in Europe most have a 1.5L engine. In Germany, the yearly tax is 2 euros per 100 cc (CO2 emissions also comes into play).
Taking 100lbs out of the 3500lb car, would effectively be a 6.38 hp gain. So weight loss can be a good investment.
"So weight loss can be a good investment."
At first glance, I thought you were talking about our weigh 
Yeah - that too! Lose 100 pounds of excessive body fat and gain 6 hp or add 75 cc engine displacement? Don't see any obese jockeys!
I used to be heavily involved in the R/C sailplane hobby. Fiberglass, carbon fiber, and kevlar cloth and weaves were used extensively. I have hollow-molded wings that are QUITE strong and very light. They are molded fiberglass with carbon strips top and bottom over the spar. Beautifully made, in Europe.
The thing is you still have resin. Resin is where the weight comes from, also how many layers of cloth, whether there is a mat or foam or some other filler in between the cloth/resin layers.
IMHO, the minor weight loss and strength gained from carbon fiber isn't worth the difference in pricing compared to fiberglass cloth. Especially in a LARGE object like a car body.
Now, if there are strips installed or patches where extra strength is needed, fine, that makes sense.
The only reason to do carbon fiber throughout is to have "bragging rights".
Wanna go faster? Loss weight behind the wheel <-- my edit of the "wanna go faster, improve the nut behind the wheel"
When you think about these cars, at 1700 - 1800 lbs. they are pretty light already and the body shape mimics a wing, so at highway speeds they tend to be even lighter the faster you go.
And you want an even lighter carbon fiber body to allow it to unweight/lift even more?
My belief is that it would become unstable at speed unless you add weight to the car, especially in the front, to keep the front wheels planted for control, which seems like it defeats the purpose of the carbon fiber bits in the first place.
Unless it’s for bragging rights as Danny mentioned, then, have at it.
@Gordon Nichols posted:Unless it’s for bragging rights as Danny mentioned, then, have at it.
Assuming one is not racing in F1, CF is always about bragging rights, as far as I can see... with the following exceptions:
- Rotating and/or unsprung assemblies and components. There are real advantages to CF wheels. Perhaps one day we'll see CF internal engine components (I can envision it being useful as a pushrod), but probably not on your grocery getter.
- Bicycle frames and forks. CF is "tunable" and can be woven to be compliant in some planes of deflection and stiff in others. This is an advantage over light metals (Aluminum, titanium, etc.).
- Aerospace applications. Who am I to say that CF in a spacecraft is superfluous.
- Biomedical devices. The possibilities here are numerous and manifold.
CF is kinda' cool looking, fully exposed or with a clear-coat tinted. However - as I have pointed out to my children on numerous occasions, "cool" never put a single grocery on my table. "Cool" is fine, as long as it doesn't get in the way of functionality.
A CF Speedster would be pretty cool, and wouldn't get in the way of anything. I wouldn't give $1000 extra for one, but I'm an old retro-grouch, and absolutely have a "form follows function" ethos (as evidenced by my haircut and wardrobe).
If this is legit, it'd be neat. I'm not going to rush out to buy one, but if the OP wants to, I'd love to follow along.
Funny, I don't really think CF looks all that cool. Let's see, I'm thinking of a black/gray spray painted rattan basket weave color scheme. What have you got?
Maybe carbon nanotubes...
IIrc Gene Berg experimented with carbon fiber pushrods back in the late '70's or early '80's. With absolutely no expansion when the engine went from cold to hot I believe the experiment didn't last long.
@ALB posted:IIrc Gene Berg experimented with carbon fiber pushrods back in the late '70's or early '80's. With absolutely no expansion when the engine went from cold to hot I believe the experiment didn't last long.
Yeah, but not every engine is a horizontally opposed and air-cooled.
One of my sons is in a club that is working on CF prosthesese and implantables like bones etc. alongside the research folks a the hospital and labs at U of Florida.
@Stan Galat posted:Yeah, but not every engine is a horizontally opposed and air-cooled.
And today, other than 'Murican V8s, there really aren't a whole lot of pushrods out there.
@DannyP posted:And today, other than 'Murican V8s, there really aren't a whole lot of pushrods out there.
... which is actually what I was thinking of.
@Stan Galat posted:CF is kinda' cool looking, fully exposed or with a clear-coat tinted. However - as I have pointed out to my children on numerous occasions, "cool" never put a single grocery on my table. "Cool" is fine, as long as it doesn't get in the way of functionality.
A CF Speedster would be pretty cool, and wouldn't get in the way of anything. I wouldn't give $1000 extra for one, but I'm an old retro-grouch, and absolutely have a "form follows function" ethos (as evidenced by my haircut and wardrobe).
Dude you twin-plugged a Type 1.
@edsnova posted:Dude you twin-plugged a Type 1.
Point taken.
I had hoped there would be a quantifiable benefit. I hope so still (as my heads languish in Denmark).
There is supposed to be a benefit to dual plugs. Like 20-25 hp worth on a hi-powered type1, if the compression is raised enough.
There can be a benefit to carbon fiber, but I believe it requires heat and pressure(in other words an autoclave). I doubt a Speedster builder would possess an autoclave large enough for a body mold. Heady technology.
To me it is all just "stupid-cool."
Medical parts are a great application.
BMW started using CF for the M series roof (replacing steel that weighted 2x the CF) - it retains the strength too. In a performance coupe you want weight low to ground (reason many 911 racers prefer no sunroof).. They also use it in costly 7 series, I8 and the I3.
When used as mirror caps and dash overlay pieces - it's just for "the" look. As a front air dam - it would be stronger than plastic so could take rough treatment better. I see many using CF drive shafts being used.
Before I retired from DOD, I over saw some work by Boeing. The then new V22 Osprey Helicopter/Plane is constructed of carbon fiber. It's big advantage over alloy is that it can be molded quickly in complex shapes and has great strength and light weight.
@DannyP posted:There is supposed to be a benefit to dual plugs. Like 20-25 hp worth on a hi-powered type1, if the compression is raised enough.
There can be a benefit to carbon fiber, but I believe it requires heat and pressure(in other words an autoclave). I doubt a Speedster builder would possess an autoclave large enough for a body mold. Heady technology.
Heat/Pressure isn’t required. The same thing can be achieved with vacuum bags and heat lamps. All the pressure/vacuum does is force the resin into the CF cloth fibers. The heat just speeds the curing process.
FWIW, the autoclave method was pioneered here in Utah at Morton-Thiokol for missile tubes. When McLaren built the first CF tub’s for F1, they were cooked here in Utah, as M-T had the only autoclave large enough to fit one. (Nowadays, they’re pretty common.)
I'm not going to argue the end process here. The benefits of reducing the resin content while still ensuring total saturation however IS the key to light weight and strength, which was my point.
Most bodies are hand layup and do not use vacuum or pressure, or heat.
At the end of the day, carbon fiber bodies in a 50s road car reproduction does not give any benefit more than bragging rights.