Carbon Fiber Doors!!!

[idar211]

I'm looking into getting a pair of CF doors for my sc and i wanted to know what you guys think. Im probably gonna go with Shaw, but if you have other suggestions ill look into that too.
I want the original look reproduction doors and i heard they never really fit right and after a while carbon fiber cracks. Im hoping it looks completely stock after paint.

This car is a daily driver, not daily but "often driver" and im concerned with the absence of no side impact safety barriers. What i want to know is, in the event of a side crash can i really be hurt with these doors as opposed to factory doors. Can it really get that serious without a roll cage. Im wanting to take off quite a bit of weight by using cf pieces, and replacing the doors could take of around 60 or 70 pounds. Is there a way to get around this? Any suggestions?

[HunterVonWurst]

Carbon fiber doors, without a cage or side-impact beams, will not offer any protection in a side-impact crash.

[Geronimo '74]

for race applications, sure.
For a daily driver, I don't see the point in having CF.

[aadrew10]

It would be cool

[Dueller]

One thing that has always concerned me re: CF doors (and CF interior door panels) is the sharp shards that are generated on serious impact.

[Noah930]

Ask Gabe (Reaper). He's gone with CF doors in his 935K3 tribute car. Uber light, but he added some sort of side impact protection (was it via rollcage?). If you can't get ahold of him on Pelican, try the Funf Gruppen and Rennlist sites. He'll also have some opinion on fit and finish, as he wasn't entirely happy with what he initially purchased from a cosmetic perspective.

[toddc]

From the potential for injury standpoint, not a good idea on a street car or any car that doesn't have a proper cage. That said, there are ways to make the carbon door a little safer. First is to use kevlar in the layup schedule, second is to use a foam core in the layup schedule. The foam adds stiffness without mass and the having a layer of kevlar as the inner-most fabric will help keep shards of carbon from penetrating the door.
Another option is to bond a carbon kevlar skin to a steel frame. This is something that I'm working on now. You get to retain the oe steel structure for things like mounting window regulatros, frames, etc. Maintains a good seal, etc. The skins will weigh considerably less than the steel skins and offer slight weight savings but the real advantage is that they will we stiff enough to run with hinges and latch for race only applications.

I can't comment on anyone else's product quality, you mentioned Shaw, but it is possible to get very good surface quality and very low shrinkage from a composite part. It's all process dependant. That said, surface quality is never goingto be as good as a steel part....

hth.

--todd

[Porsche-O-Phile]

To replace the outer skins would make sense but for anything other than a dedicated race car I'd be leery of compromising the interior structural panel for exactly the reasons mentioned above.

CF doesn't bend, it explodes. And that stuff is sharp. If something hit an outer door skin and shattered it, it'd probably be okay since you'd still have the metal cage between you and it.

However the biggest weight savings would come from replacing the relatively heavy metal structural frame, so I'd think "race only" application.

What do fully CF cars like the Koenigsigg do? Are there metal interior strucural tubes or something for the CF to bolt up to or what?

[911st]

Agree, carbon doors require a roll cage. Neither a roll cage nor carbon doors are going to be safe on a street car no matter how cool they are.

See if you can find your weight loss first in other places. Lids, glass, seats, exhaust, interior, sun roof, fenders, exhaust, glass, wheels, alloy brake calipers, alloy front a arms w coil overs, bumpers. An AAA card is a lot lighter than tools, jack & spare. Then there is also eating a little less pizza.

There is something about how well a stock door fits that a light weight door will probably never be able to approach.

[joe payne]

now these are carbon fiber doors!

[HawgRyder]

What ever happened to the old lightening methods?
How about acid-dipping?
We used to use that for drag cars....pulled out several hundred pounds on a 67 Ford.....took it from 3365 down to 2480.
Bob

[RWebb]

Originally Posted by idar211

... in the event of a side crash can i really be hurt with these doors ...

uh


YES

unless you have a very early car w/o safety beams - in that case the difference in safety between CF and the stock thin sheet steel doors would be reduced - I suppose there is some enhanced risk from having splinters of CF rip into your body -- lots of surgeon time to go after those

don't forget - the least important place to reduce wt. is in the center of the car and low to the ground

[boba]

I used a CF race door more for the clean cap, as I was not going to be running windows. We added a halo bar from the main hoop around and out near the door skin and under the dash. This halo bar was also tied in to the front shock towers. A thin AL inner skin was formed and than upholstered in matching leather to finish off without raw CF next to driver and passenger.

[Drisump]

IMHO, I appreciate a light sports car as well as the next Porsche nut but, I think it would get kind of old to have to crawl over a cage to get into a DD (plus the cage does weigh a fair bit) and having either a non functioning or "side curtain" type window on a DD seems excessive. I think hundreds of pounds can be saved in other areas first. One of the threads on this board asks "how much do you weigh?" Some of these guys have put their cars on draconian diets resulting in rather surprising weight savings. Being a back-packer, I know how a few onces here, and a few onces there soon add up to real weight. I guess the doors, being such large panels, draw attention to themselves and it becomes tempting to "swing for the fences" as far as weight savings go. If weight is what you want to shed, you should maybe try to contact some of those "gossamer" 911's on the thread first. Good luck in your quest

[rob930]

If you have money to burn FVD has some with beams. I think they were about $4,500 a piece.

[RWebb]

there is a near exponential increase in cubic dollars as your car's diet progresses past the low hanging fruit

to modify an old adage: Lightness costs money. how fast do you want to go?

The ultimate guru of Porsche wt. reduction (at least of the ind. contractor class in the US) once laid out the $$/lb. ranges for different race classes. I forget everything he said, but at some (elevated) levels people will pay in the neighborhood of $10,000 per lb. of wt. removed.

YMMV.

[pksystems]

Originally Posted by joe payne

now these are carbon fiber doors!

Any more pics of those?

[idar211]

Thanks for all the valuable advice guys.
Im kinda new to this lightening thing, and even tho i want my porsche to go fast im a sucker for creature comforts. So maybe its not for me, because i really do enjoy leather, ac and a nice stereo!

[BigD9146gt]

Originally Posted by pksystems

Any more pics of those?

Those look very familiar to a clients' 997 GT3 CUP S, as well as the cage... I assume the 997 GT3 RSR has them as well. Come to think of it, I've worked on a couple 996 GT3 caged cars with doors like that, but a little different in shape.

[turbobrat930]

I have CF doors on my race/street car. I also have a full cage in my car as well. The doors were from M. A. Shaw and are excellent quality.