carbon fiber less weight?

[bensenvill]

Just the doors really would be really unsafe in a street car. There is some risk with a poorly designed CF hood, and with poorly designed CF seats as well, but the doors by thier nature are dangerous without a cage that has door impact bars. And by 1/4 panels, I'm assuming you mean front fenders, because the rear 1/4s are part of the unibody and not easily swapped out for composite materials.

very correct.. although I would argue that any 'CF' hood that exists for our car isn't really a safety risk [because the bulk of it still is fiberglass wrapped in a bit of CF for looks]. Now if we were talking a pure CF hood, your talking about 2 pounds rather than the 12-13 pounds for the ones available [I am certain I can make a hood under 2 pounds with more stiffness than the stock], but BUT I can also see it being rather unsafe in a front end collision. If you notice on the stock hood there are creases in the underbody support for crumple zones. I'd worry about being decapitated.

 

[csvtjohnga]

cf konis
cf uim/lim
cf fuel rail
cf maf
cf sway bars
cf fog light mod

 

[Beans]

cf konis
cf uim/lim
cf fuel rail
cf maf
cf sway bars
cf fog light mod

cf gas tank
cf rear sub frame
cf wheels
cf tires
cf turbo
cf piping
cf FMIC
cf brakes
cf brake pads
cf calipers
cf brake lines
cf exhaust
cf y pipe
cf cat
cf headers

 

[jamesmason1]

Just the doors really would be really unsafe in a street car. There is some risk with a poorly designed CF hood, and with poorly designed CF seats as well, but the doors by thier nature are dangerous without a cage that has door impact bars. And by 1/4 panels, I'm assuming you mean front fenders, because the rear 1/4s are part of the unibody and not easily swapped out for composite materials.

Ya I know the doors would be really unsafe, and yes the fronts are what I'm referring to, the rears would be near impossible even with extensive fabbing. the question was the weight though not the safety, because I know each one of those doors is over 150lbs. so making it c/f and engineering it for the stock windows, locks, and interior panels would still cut 2/3rds the weight off each door. I personally wouldn't do it but it would take some serious weight off.

 

[Bugzuki]

I think that it is impossible to generically say that carbon fiber doors are unsafe. If there is structure built into it it can be safe. At Western Washington University we built a car almost completely out of Carbon Fiber. We had a steel rear space frame and Steel front space frame. We had a 100 horsepower electric motor in the front and a 100 horsepower honda natural gas engine in the back. When it was finished it weighed in right around 2200 lbs. We were clocked with a 0-60 time of 5.2 seconds.

We did extensive testing with computer controlled presses. We measured what it took to crush steel car doors out of a honda and a couple others. We designed the carbon fiber door to hold more then that. It was also much lighter.

Oh - I forgot to add this was a 1 million dollar government grant vehicle design to sustain life in a 50 mph crash into a bridge pillar. But, we never got in a accident, so did not properly test it.

I also do not think the would be a huge chance of the hood to come through the window - I think it would be more likely to get crushed and go over the window.

http://vri.etec.wwu.edu/viking_32_photos.htm

 

[jamesmason1]

Oh - I forgot to add this was a 1 million dollar government grant vehicle design to sustain life in a 50 mph crash into a bridge pillar. But, we never got in a accident, so did not properly test it.

I'm sure that a million dollars is out of my budget and the cost of fabbing the doors with an impact brace setup would be very expensive and also wouldn't yeild nearly the amount of weight reduction that a full c/f door structure would and that in it's self would not make it cost effective to build it that way. this is why I wouldn't do it either way but am curious to the total amount of weight reduction.

 

[bensenvill]

And my project was a solar powered hydrofoil. 17' long cf/kevlar hull, fully loaded including myself weighted 300#'s and topped 40mph. Every single part hand fabricated by myself and 2 others.

Your missing the point. CF does not 'break' the same way steel does. It has a wonderful tendancy to SHATTER, so crush strength is really irrellavent.

I think that it is impossible to generically say that carbon fiber doors are unsafe. If there is structure built into it it can be safe. At Western Washington University we built a car almost completely out of Carbon Fiber. We had a steel rear space frame and Steel front space frame. We had a 100 horsepower electric motor in the front and a 100 horsepower honda natural gas engine in the back. When it was finished it weighed in right around 2200 lbs. We were clocked with a 0-60 time of 5.2 seconds.

We did extensive testing with computer controlled presses. We measured what it took to crush steel car doors out of a honda and a couple others. We designed the carbon fiber door to hold more then that. It was also much lighter.

Oh - I forgot to add this was a 1 million dollar government grant vehicle design to sustain life in a 50 mph crash into a bridge pillar. But, we never got in a accident, so did not properly test it.

I also do not think the would be a huge chance of the hood to come through the window - I think it would be more likely to get crushed and go over the window.

http://vri.etec.wwu.edu/viking_32_photos.htm

 

[Bugzuki]

Your missing the point. CF does not 'break' the same way steel does. It has a wonderful tendancy to SHATTER, so crush strength is really irrellavent.

I am not missing the point. I understand full well that carbon fiber shatters. My point was that you can engineer carbon fiber to handle specific impacts. You just need to know what forces it will see to make it strong enough. But, this is probably a worthless arguement, since nobody is going to make a carbon fiber door for the Contour.

The Hydrofoil sounds like a cool project.

 

[bensenvill]

lol, I was mainly fighting you on semantics, crush strength does not equal impact resistance.

Although I shouldnt say much, my testing solely consisted of seeing if I could slam a screw driver through the boat.

making doors for the contour wouldn't be impossible [assuming you can forgo windows and window frames]. doing the cougar would be much much easier.

 

[Escortrs88]

When building our Mustang we put in a Racetech Carbon Kevlar driver seat. It was about the same weight as the 6-point harness we also put in. Due to cost we put in a metal frame Recaro for the passenger.

I do like the CF windshield, I think I might have to try that on our car.

Does anyone know where I can find a CF 5.0L V8 block. We have too much weight over the front end, so a CF block might help that.

About CF doors, I was reading that they are starting to design CF door crush boxes for racing cars. Its like the crush box on the front of a F1 or LMP car but used in the doors for side impacts.