carbon fiber...why not?

[dzolcali]

carbon fiber hoods and fenders would be nice...lighten the load and increase MPG sure they look rice but you know as well as I know they weigh less...

is there anyone that can mold out a CF hood or fenders for the xj?

maybe even a cf driveshaft? I've heard of these before, supposedly they are nice

[BrettM]

never heard of or seen a CF driveshaft, and it would definitely be a bad idea for something that gets wheeled.

there are fiberglass hoods and fenders out there, I don't see why you would need the greater strength of carbon fiber

[Matt S.]

never heard of or seen a CF driveshaft, and it would definitely be a bad idea for something that gets wheeled.

there are fiberglass hoods and fenders out there, I don't see why you would need the greater strength of carbon fiber


Brett... isnt it obvious?

Oak is out, and Carbon Fiber is in. Didnt you get the memo?
http://www.naxja.org/forum/showthread.php?t=39026&highlight=wood+driveshaft

[old_man]

Hood maybe, fenders or drive shaft, noooooooooooo wayyyyyyyyy

But if weight were an issue I wouldn't be running .25" armor plate under the whole vehicle. :jester:

[5-90]

CF composite body panels would make some sense - and if you're worried about "looking rice," I'm sure the resin used as a binder can be coloured - I haven't checked, but I think it's two-part polyurethane or two-part epoxy anyhow, which I know can be coloured.

Or, just make sure the surface can be scuffed and painted - problem solved.

5-90

[tealcherokee]

alot of companies with IRS vehicles use a carbon PROPELLER shaft (no slip, no movent, just spins). I know the nissan 350z has this. as far as a CV shaft, i dont know if itll work

[ROBZ95Xj]

maybe even a cf driveshaft? I've heard of these before, supposedly they are nice
you need to stop playin video games

[Michaelarchangelo]

you need to stop playin video games


Umm, there are CF driveshafts out there. They are really expensive, but light and strong. As far as off-roading, it would be a really bad idea. CF won't stand up to side blows very well, hit one rock and that would be it.

[Skullver]

carbon fiber hoods and fenders would be nice...lighten the load and increase MPG sure they look rice but you know as well as I know they weigh less...

is there anyone that can mold out a CF hood or fenders for the xj?

maybe even a cf driveshaft? I've heard of these before, supposedly they are niceWe are actually working on some CF fenders,hood, dash panel, louvered side panels etc. for our Jeepspeed rig, it is pricey stuff but with a foam or fiberglass core it would only be skinned with CF or hybrid(CF/Kevlar). Def not for the ricer look but more for function/durability and it would shave a little weight. My buddies just happen to build UAVs(unmanned aerial vehicles)and they are composite guys so it was something we are kicking around for future production. It was their idea so I am just going along with it but we will let you all know how it turns out. As for the driveshaft...doesn't sound too safe.

[Weasel]

CF is expensive stuff but if you want the lightest strongest whatever then get out the wallet. While not impossible it's quite a bit more difficult to make structurly sound thus the cost and materials arn't cheap either. As for CF driveshafts, it could be done, and stand up to the abuse, all depends on the design and how it's made.

[BrettM]

We are actually working on some CF fenders,hood, dash panel, louvered side panels etc. for our Jeepspeed rig, it is pricey stuff but with a foam or fiberglass core it would only be skinned with CF or hybrid(CF/Kevlar). Def not for the ricer look but more for function/durability and it would shave a little weight. My buddies just happen to build UAVs(unmanned aerial vehicles)and they are composite guys so it was something we are kicking around for future production. It was their idea so I am just going along with it but we will let you all know how it turns out. As for the driveshaft...doesn't sound too safe.
you going to sell them? don't they have to be available to the public to be JeepSpeed legal?

[Matt S.]

you going to sell them? don't they have to be available to the public to be JeepSpeed legal?


I think the only class regulations as far as public availability is suspension and drivetrain. I could be wrong, but i think its like that. The cages are obviously not aftermarket ready.

[Skullver]

you going to sell them? don't they have to be available to the public to be JeepSpeed legal?I am thinking that is only for suspension systems/componenets, will double check w/Clive but hopefully it does not apply to body panels etc. We have a buddy that does some class 8 dez racing and he is also interested. It hasn't really gone any farther than the planning stages so we will see how it turns out. They would like to sell them but it may not be economical, we will see what happens. I also have a yota I will be working on for the dez so that will be another canditate/experiment. Thanks Brett, hadn't really thought of the JS legality thing.

[BrettM]

Major components, such as suspension kits, must be readily available to the general public. Unless a modification is allowed or component listed as open herein, that part must remain original. Any component or assembly can be strengthened by adding material, but the original must remain intact.


1.1.1Body:

1.1.1.1 Stock unit construction body only. All body panels must retain original dimensions and material type (except front fenders, hood and fender flares). No internal body structure may be removed unless noted herein, except to allow passage of roll cage tube (where the hole must be welded closed using material of the same thickness removed. The stock rear upper shock mount crossmember may be removed or modified for installation of under-floor fuel cell. Stock seams may be rewelded, and material added for strength.

1.1.1.2Front fenders and hood may be replaced with units of any material. Fenders may have additional flare and wheel arch, but must have basic appearance of stock Jeep XJ model bodylines. Front bumper may be trimmed to match the new fender openings.

I think you'll be fine, but I would definitely check before that kind of investment of time and money.

[Matt S.]

Excuse me gentlemen...


We don't allow tech on NAXJA anymore. Go away and let people oogle over this great idea.

[dzolcali]

they do make carbon fiber drive shafts for racing..thats why I asked...not everyone goes and takes their jeeps into rocks and shit..some people drive on the roads. As far as panels and hoods, I was just think gas is going up and the xj weighs a bit, and ever little bit helps...cf is strong and durable when done correctly. Another thing to add, there is a carbon fiber shortage currently which will make your endeavor with the manufacture of cf parts more expensive, currently the aerospace industry has first dibs on all fiber material for the carbon fiber mixture as far as I know.
Also, heres a quick bit of info, carbon fiber is not used on planes...why you ask? Because planes get struck by lightening very often, it cascades over the capsule...however if the plane were made of carbonfiber and were stuck...lol goodbye plane and passengers. dun dun dun...NOW YOU KNOW!

[BrettM]

they do make carbon fiber drive shafts for racing..thats why I asked...not everyone goes and takes their jeeps into rocks and shit..some people drive on the roads. As far as panels and hoods, I was just think gas is going up and the xj weighs a bit, and ever little bit helps...cf is strong and durable when done correctly. Another thing to add, there is a carbon fiber shortage currently which will make your endeavor with the manufacture of cf parts more expensive, currently the aerospace industry has first dibs on all fiber material for the carbon fiber mixture as far as I know.
Also, heres a quick bit of info, carbon fiber is not used on planes...why you ask? Because planes get struck by lightening very often, it cascades over the capsule...however if the plane were made of carbonfiber and were stuck...lol goodbye plane and passengers. dun dun dun...NOW YOU KNOW!
how many mpg do you expect to gain by loosing a few pounds in the fenders and hood? how many miles, even at $5/gal, would it take to make up for the cost of making those?

[MogifiedXJ]

they do make carbon fiber drive shafts for racing..thats why I asked...not everyone goes and takes their jeeps into rocks and shit..some people drive on the roads. As far as panels and hoods, I was just think gas is going up and the xj weighs a bit, and ever little bit helps...cf is strong and durable when done correctly. Another thing to add, there is a carbon fiber shortage currently which will make your endeavor with the manufacture of cf parts more expensive, currently the aerospace industry has first dibs on all fiber material for the carbon fiber mixture as far as I know.
Also, heres a quick bit of info, carbon fiber is not used on planes...why you ask? Because planes get struck by lightening very often, it cascades over the capsule...however if the plane were made of carbonfiber and were stuck...lol goodbye plane and passengers. dun dun dun...NOW YOU KNOW!
You would never recover the cost of the intitial investment of the carbon fiber panels in gas savings. The wieght difference would be nominal at best...just take a big shit before you drive...it would be cheaper and proabably save you the same amount of wieght...just a thought though.

[dzolcali]

lol...ok well what about added horsepower...it would def help in that situation as well...for those of us who like to squeeze extra hp out of an engine...also known as "free horsepower" when you lighten the ride more horsepower is available since it has less weight to carry..this is all elementary stuff..but seriously, cf is not so bad i dunno why so many people hate on it...ive had too much fiberglass break on me and it's expensive as well...

[MogifiedXJ]

I've heard racing stickers will give you more hp while giving you more miles per gallon as well...


























Seriously though, They're cheaper than carbon fiber body panels. :wierd:

[Matt S.]

lol...ok well what about added horsepower...it would def help in that situation as well...for those of us who like to squeeze extra hp out of an engine...also known as "free horsepower" when you lighten the ride more horsepower is available since it has less weight to carry..this is all elementary stuff..but seriously, cf is not so bad i dunno why so many people hate on it...ive had too much fiberglass break on me and it's expensive as well...

:repair: :repair: :repair: :repair:

do some of that.. start getting some real life experience then tell us all that stuff will help.

My question is this, if those ricer boyz have all that CF, why are they still slow? I have seen 5000lbs run twice as fast down a stip as a ricer. Or how about ralley. Those guys dont have loads of CF, they wieght around 3500. About the same you XJ wieghts.

I say... if you want to learn wtf we are all talking to you about, learn to listen to THOSE WHO HAVE A CLUE. ok? Don't ask questions just to ask them, because they have been asked already.

[dzolcali]

scrappy...sorry and nothing intended but XXXX off please...your following me around in my threads just bashing on me for whatever reason...cf is lighter, and strong...if I had a choice to race something it would be a 1969 beetle, i'm sure a beetle can beat your 5000lb monster beast thats so fast. hypothetical races online are great keep it going. No question is a stupid question and i don't ask questions just to ask them...if no one asked questions on naxja, people wouldn't be able to search for things. And I do wrench on my rides...I lowered my s10, I put an exhaust manifold, exhaust pipe, fitted a full fiberglass and polyurethane body kit on a talon tsi awd, installed boost gauges, egt gauges, many of other things, i repaired the front end of my jeep and banged out all the mounting brackets...I just repaired a ford aspires entire front end, including radiator, tail lights, headlights, pulled metal out, corner lights, bumper, and hood and hinges...I'm not an idiot, maybe I don't know shit about lifting a jeep, i'm learning just like you did scrappy the first time you touched a wrench. quit being a hater and leave me alone...K thanks

[Matt S.]

:shhh: :puke:

[BrettM]

No question is a stupid question

not around here :laugh3:

admit it, you want carbon fiber because you think it's "cool". the sooner you admit it, the sooner we can get on with a (half)serious discussion about how to make some.

[dzolcali]

carbon fiber isn't really cool. I think it's ugly, and all the ones i see on peoples hoods are chipped up or sun faded. I was mainly just looking for a way to lighten up my jeep I searched and couldn't find a hood other than the cowl inductino hood I figured carbon fiber was out of the question yet, naxja forums tend to turn up good info occasionally on things i haven't yet discovered online by searching. Thats why I posed the question. In which I found that someone here is possibly making some things made out of CF :)

good cf is ok I guess...it could be cool on a jeep since no one has any. People talk about lexan windows and stuff and thats all fine and dandy i say, carbon fiber and everyone jumps my nuts about it...wtf

[BrettM]

so what more reasonable weight reduction efforts have you made?

[Matt S.]

oh oh oh!!! I know! I know!:sunshine:



none.

[dzolcali]

none, i've actually gained weight, and once the lift is on, will continue to gain weight, thus the reason to counter that with lighter other things. It's a DD as well, I don't want to rip out the interior and drive girls around in some beat up internal junk...I want to set everything up all smooth and aesthetic, yet functional, nothing wrong with that last time i checked. good call scrappy...minus the S

[BrettM]

the point is, there are more cost effective ways to loose weight. if you've already done all of those, then sure, start looking at the hood and fenders.

[chrslefty]

CF composite body panels would make some sense - and if you're worried about "looking rice," I'm sure the resin used as a binder can be colored - I haven't checked, but I think it's two-part polyurethane or two-part epoxy anyhow, which I know can be colored.

Or, just make sure the surface can be scuffed and painted - problem solved.

5-90


actually you can get colored carbon fiber : red,blue,yellow and grey .i think that there are more but i cant remember what they are ill look for the site again to see.

i thought that a CF hood would be sweet to set up as a heat reduction hood with a cowl in front and vents in the rear. also CF has (from what i read ) better heat dissipation than steal or fiberglass . which would help with a hot engine compartment!

[XJ Un-Limited]

they do make carbon fiber drive shafts for racing..thats why I asked...not everyone goes and takes their jeeps into rocks and shit..some people drive on the roads. As far as panels and hoods, I was just think gas is going up and the xj weighs a bit, and ever little bit helps...cf is strong and durable when done correctly. Another thing to add, there is a carbon fiber shortage currently which will make your endeavor with the manufacture of cf parts more expensive, currently the aerospace industry has first dibs on all fiber material for the carbon fiber mixture as far as I know.
Also, heres a quick bit of info, carbon fiber is not used on planes...why you ask? Because planes get struck by lightening very often, it cascades over the capsule...however if the plane were made of carbonfiber and were stuck...lol goodbye plane and passengers. dun dun dun...NOW YOU KNOW!

I beg to differ on the CF not being used on airplanes, or any aircraft for that matter for structural use. The entire aircraft isn't made of the stuff, it's way too brittle, but sections and panels are, such as tails, doors, and non-load bearing frames. There is a metal mesh layed into the mold (imagine window screen in the layup), to dissipate any electrical influences (lighting, static discharges).

It would be a great way to reduce weight and not lose strength, but would the cost effectivity outway any long term benefits? That's what I would have to ask myself. If you can afford it, by all means go for it.

How about using aluminum, such as 2024-T3? I don't know of any place offering body panels made of it, but the weight difference is just as substantial. The body lines on the XJ are pretty basic, so it would'nt be too terribly hard to form.

[dzolcali]

good post, the whole airplane thing was told to me through a meteorology course, the instructor happen to be a airplane pilot as well and thats what he had to say about carbon fiber being used for airplane fusaloge sp?

[Michaelarchangelo]

I know of a few military planes made with cf. I know that when used for something like a driveshaft part, gains of upto 5% can be expected.


Also, the reason most "ricers" aren't fast with cf products are because: 1) it is usually cf laid over fiberglass 2) they weren't that fast to begin with.

The general rule of thumb is for every 100lbs you lose of sprung weight, you gain .1 seconds in the 1/4 mile. So if you shed 200lbs by using cf, you only gain roughly .2 of a second (so instead of a 16.5 you run a 16.3).

CF bodypanels are pretty pointless for most xj owners, but a cf hood could be useful, because you can make it vented or have a larger cowl.

[streetpirate]

so...

you know you could aways just buy a fiberglass hood and fenders, right?

http://www.hannemannfiberglass.com/Jeep_Commanche.html

and i think rustys sells nonflared fenders

[streetpirate]

if i hadt he extra money i would love to make a widebody street jeep with hannemann's stuff. the bedsides would work perfect on a 2 door, with the 6" flares up front

[woody]

I think another reason CF is used in racing driveshafts is safety... when a steel or alum shaft checks out, the (relatively large) pieces of it will carry some energy. When a CF shaft checks out, it disintegrates into a gazillion little lightweight pieces that carry very little energy.

[dzolcali]

yay, so I guess i'm super stupid for suggesting a carbon fiber drive shaft...evidently thats what everyone in my other thread has concluded. Perhaps for off road it is dumb, but I never specified an off road jeep cf driveshaft...oh well thats what assuming does..majority rules, i'm an idiot

[MogifiedXJ]

i'm an idiot

Yes...Yes you are. There is good news though...realizing it is the first step in the process. Now you need to work on not being an idiot. Seriously though, carbon fiber drive shafts have thier place...just not in the jeep world.

[dzolcali]

mog I resent that comment, i'm not stupid at all, in fact i'm working on my masters right now, theres was a big hint of sarcasm in that "i'm an idiot" statement. it would be nice if people would just either say, nothing if they don't know about something i'm posting about, or, if they do know like those mentioned above about the carbonfiber shaft splittin up etc...would either discuss it, or say "yeah that would work but not in the jeep world"
life could be so much happier if people would do that. I don't go to the tranny tech forums and start talking about splines and shit, cause I don't know anything about them I have no clue why other members here attack my post when they know or completely missed the meaning of the threads.

[djblade311]

mog I resent that comment, i'm not stupid at all, in fact i'm working on my masters right now, theres was a big hint of sarcasm in that "i'm an idiot" statement. it would be nice if people would just either say, nothing if they don't know about something i'm posting about, or, if they do know like those mentioned above about the carbonfiber shaft splittin up etc...would either discuss it, or say "yeah that would work but not in the jeep world"
life could be so much happier if people would do that. I don't go to the tranny tech forums and start talking about splines and shit, cause I don't know anything about them I have no clue why other members here attack my post when they know or completely missed the meaning of the threads.

"yeah that would work but not in the jeep world"

k. Now that thats settled...how about CF bumpers? LOL

[wacho4]

... Seriously though, ...
I would assume that means he was not being serious before these words, chill man. Not that I blame you, since some layed into you a little harshly.

Back on topic...
Just for curiosty's sake:
Say I had bushwacker flares or the like. Can those fiberglass fenders be cut to adapt them? I know it wouldn't make sense price wise, to buy these just to cut up. And that's why I wouldn't do this anyway. I guess what I'm really asking is: 'Would this make the front match the rear flares nicely?', or 'How stupid would this really look?' Just another idea bouncing around in my head ready for someone to shoot it down.

[MogifiedXJ]

I would assume that means he was not being serious before these words, chill man. Not that I blame you, since some layed into you a little harshly.

Back on topic...
Just for curiosty's sake:
Say I had bushwacker flares or the like. Can those fiberglass fenders be cut to adapt them? I know it wouldn't make sense price wise, to buy these just to cut up. And that's why I wouldn't do this anyway. I guess what I'm really asking is: 'Would this make the front match the rear flares nicely?', or 'How stupid would this really look?' Just another idea bouncing around in my head ready for someone to shoot it down.
That is what I meant by seriously though.

Assuming the fiberglass fenders you bough retained the shape of the original fenders I don't see why you couldn't cut them and adapt the bushwackers. However, you can order the fiberglass fenders with a six or eight inch flare built in so I wouldn't really see the point.

[dzolcali]

if you got the money do it...I mean people always ask "why would you want to do that" you should be like "cause I work and i make money and you buy what you buy, i'll buy what i buy and decide whats a waste for myself" and then you cut your flares up and put cf everything on them and then blow it up and buy another jeep and say see what now?

[wacho4]

The point? just to match the front to the rear.Like I said just a crazy idea i had when i was considering fiberglass fenders after looking at the prices on Bushwacker flares. Like dzolcai says, 'if I have the money why not spend it all on crazy messed up shit that will just fall apart and I can say seewhat now?'.
Someone needs some valium.
But seriously, it was not something I seriously considered. I was just wondering if any body had seen something like this and could tell me how stupid it looked.
Also, Just wanted to blossom forth another idea I had that made no real sense. Its what I'm good at. Seriously

[Weasel]

Also, heres a quick bit of info, carbon fiber is not used on planes...why you ask? Because planes get struck by lightening very often, it cascades over the capsule...however if the plane were made of carbonfiber and were stuck...lol goodbye plane and passengers. dun dun dun...NOW YOU KNOW! Your an idiot. Thats why the F-22 is mostly composite right? Oh and I suppose you know about the plane Boeing is starting to built that is entirly composite as well. There's that other little plane company, um I think called Airbus?, that building one as well. I beg to differ on the CF not being used on airplanes, or any aircraft for that matter for structural use. The entire aircraft isn't made of the stuff, it's way too brittle, but sections and panels are, such as tails, doors, and non-load bearing frames. See above, planes already use C.F. rudder assemblies. While yes it is brittle in the sence that fiber break or shear, the point at when the shear should be thought about. 300m will fail around 260-280 ksi maybe 300ksi. Carbon will fail at about 620ksi, and depending on the setup can have even higher strengths. So yes it will have a brittle failure but the point at which it fails, steel would have said bye-bye much earlier.

The problem with carbon is it's depenant on layers, which are usually uniform and contain air bubbles, gaps, ect. The cross section are not nearly as nice as steel is. You have problems with internaly cracks froming in these gaps, usually the fiber will stop the crakc from spreading but it still could cause a failure point. Another problem is external abrasion that would crack or break fibers. Since the fibers are what carry the load and breaks will reduce the amount that fiber can carry and possible weaken the structure. There are ways around this problem though. Another problem is direction of the fibers. Composites are usually the strongest in tension, not compression or bending (Kevlar and Boron are better in compression). This means multiple layers need to be run so there are always fibers in tension, carrying the load. Froming composites is fun to say the least. Layup and molds take tons of time and material is hard to get and expensive. Most of the stuff built is overbuild cause of the uncertainties, increasing the weight and cost. Resign also adds to the weight as most parts need to be about 30-40% fraction of volume but end up higher at 50-60 due to layup proccess.

From an engineering stand point composites are a completly new field and analyis of them is difficult to say the least. You can't treat the compounent as a solid piece like steel because we don't really have a good idea how stress travel between layers or how they effect the stress and strain. Finite is the only way to analyize a composite parts and even then it's a mess.

Carbon on Jeep parts? Sure why not. It could be done but several things need to kept in mind. Rock damage and scars could be dealt with creativly. I know a little about composites but really not all that much overall, just stuff I've picked up here and there form a few parts I have helped make and listening to others, plus a few classes.
Actually no one is really an expert on the stuff even the guys at Boeing are finding out new things all the time, so I'm not really sure anyone here should be running their mouth as the formost expert on the stuff.

[Boulder_jeeps]

whats wrong with a carbon fiber drivshaft? My audi came stock with a carbon fiber drive shaft. Audi has been installing carbon fiber drive shafts on their cars for years. (just my $.02)

[MogifiedXJ]

whats wrong with a carbon fiber drivshaft? My audi came stock with a carbon fiber drive shaft. Audi has been installing carbon fiber drive shafts on their cars for years. (just my $.02)
It's fine for an Audi...

But jeeps aren't audis now are they??? Aside from the tremendous cost it would take to make a custom one for a drive shaft...what would be the point??? The carbon fibershafts are used to attain less rotational mass just like light wieght flywheels so the motor and drive train can spool up quicker. Jeeps aren't race cars...Period. They don't need carbon fiber shafts. Besides one hit off-road and it would be gone...all that money down the drain.



Let this thread die people.

[cumorglas]

I used to work in the racng sailboat world. On those boats a few pounds saved at the masthead meant hundreds of pounds of ballast you could ditch or more stabiity and more sail for the same weight. either way money spent on carbon masts and mastheads pieces was money well spent.

Then the berlin wall fell and defense spending just stoppped.in the early 90's prepreg got so cheap that some Maxis (70 foot moey no object class) got built with all carbon hulls. there was even a point when a f9 racing trimaran could be had in carbon for only 15 grand more than straight up fiberglass, those days are long behind us now as most of the smart boms and missiles we use now have driven the price of carbon fiber right back into astronomical territory. but it s still nice to dream.

by the way building the autoclave to bake the hood fender combo would be much easier the the one to bake the hundred foot long mast.

[5-90]

Just to weigh in...

I'd think CF/Composite might be more useful for interior parts than exterior - while CF might have good strength for its weight, once you disturb the panel (rocks, anyone?) you start losing that strength at an alarming rate.

It's also true that you gain range for lost weight ("If it doesn't make you go faster, it slows you down,) but the weight savings for the strength you actually end up LOSING just isn't there. The nice thing about metal - it can be reformed after being dented, most times.

Start by removing interior you don't need. Don't use the back seat? It's gone. Don't use the OEM roof rack? Fill the holes with well nuts and brass screws - and give yourself another about 12 pounds that doesn't do anything.

Strip the interior panels - they're worth a few pounds as well. Don't bother with the centre console (it doesn't weigh but about four pounds, and can be useful later on) and stripping the lower IP fascia would be of dubious utility as well.

Polycarbonate windows? Maybe useful - but keep the windscreen and front door windows in safety glass - if something happens and you hit those windows, you actually WANT them to break...

Dieting is going to be a little tricky beyond that point - how much strength do you want to lose in order to lose weight?

Another thing to think of is going to be cost - not only will you want a vacuum chamber (for mixing the binder - vacuum will get rid of air bubbles after you mix it...) but one-off layups are Hellishly expensive, and it will probably cost more than KBB on your XJ.

There was a joke about how fibreglas toilet seats on a military aircraft (P-3 Orion ASW, I think) ran $40K a copy. But, it's not a joke. I had occasion to talk to someone who was involved in that project (Andy Masto, ran the machine shop I used to use,) and the company was actually LOSING money at that price! They didn't have a big enough order (in pieces) to justify making a layup jig for that pattern, so each piece was laid up by hand. Not factoring in the MIL-spec paperwork and admin time that it entails, each unit cost about $30K (just in design time, engineering to fit it into the specified space, and meeting FAA & aero parts specs.) The MIL paperwork damn near doubled that cost - they sold each unit for about $40K (per bid submitted,) but the actual cost for each piece was more like $50K or so, once all the design and engineering and SPEC paperwork and FAA tracking was factored in. (Curious thing about AN/NAS spec hardware - did you know that the lot numbers on the box can track the thing back to what spadeful of or that the base metal was smelted from? No joke - no wonder Aero stuff costs so damn much...)

I'm not trying to shoot down the idea - just letting you know what you could be getting in for. How bad do you want to do this? There are easier ways to put your rig on a diet - and cheaper, and probably more effective.

5-90

[dzolcali]

i didn't want to rip my interior out so that I can still invite women inside and not disgust them at my piece...that was the basic point of the exterior CF stuff..what about titanium as a drive shaft substitute, or other light weight alloys are they just not strong enough to work as a driveshaft or is it just price and demand like most things.

[MogifiedXJ]

i didn't want to rip my interior out so that I can still invite women inside and not disgust them at my piece...that was the basic point of the exterior CF stuff..what about titanium as a drive shaft substitute, or other light weight alloys are they just not strong enough to work as a driveshaft or is it just price and demand like most things.


http://www.naxja.org/forum/showthread.php?t=39026

[5-90]

i didn't want to rip my interior out so that I can still invite women inside and not disgust them at my piece...that was the basic point of the exterior CF stuff..what about titanium as a drive shaft substitute, or other light weight alloys are they just not strong enough to work as a driveshaft or is it just price and demand like most things.

Titanium will cost WAY too much to machine into a driveshaft, and the material will be nuts anyhow. Stick to steel, just to be safe (Jeep driveshafts get abused...)

Next option - get a second rig for a DD, and build one the way you want and the other for "socialising."

You know, I just keep finding advantages to being married and having more than two rigs (one for each of us, and a few "projects..." And a spare.)

5-90

[Michaelarchangelo]

Titanium is a PITA to work with. Your best bet for a driveshaft is to go with aluminum if you really want a weight reduction that bad. Plus, what is the need for all these cf parts on the trail? It isn't like you haul ass there and need all the power you can get.

[dzolcali]

mpg...simple enough, sure it won't counter the money spent to save the extra mpg, but it will help the environment in the long run if more of us realized that what we drive does hurt the environment whether it be a honda that gets 40 mpg, or a jeep that gets 16 or what have you. Until an alternative fuel source is widely available I would like to lighten my load and get more use out of the fossil fuels i'm burning as opposed to save a dime or two vs. save a buck or two.

[streetpirate]

hey, the less gas you use the more there is for me

[BrettM]

mpg...simple enough, sure it won't counter the money spent to save the extra mpg, but it will help the environment in the long run if more of us realized that what we drive does hurt the environment whether it be a honda that gets 40 mpg, or a jeep that gets 16 or what have you. Until an alternative fuel source is widely available I would like to lighten my load and get more use out of the fossil fuels i'm burning as opposed to save a dime or two vs. save a buck or two.
have you considered the environmental ramifications of the technology you wish to incorporate versus the eviromental savings of the 5 gallons of gas you will save over the next 100,000 miles?

If you don't drop it, I'm going to go burn 5 gallons of gas in the yard, just for you.

If you're doing it for power, you're barking up the wrong tree.
If you're doing it to save money, you're barking up the wrong tree.
If you're doing it for the environment, you're barking up the wrong tree.

This is all very rediculous, if you want to do it just for the hell of it, then just do it.

[Michaelarchangelo]

If you are really concered about the enviroment, why are you driving a jeep?

[5-90]

mpg...simple enough, sure it won't counter the money spent to save the extra mpg, but it will help the environment in the long run if more of us realized that what we drive does hurt the environment whether it be a honda that gets 40 mpg, or a jeep that gets 16 or what have you. Until an alternative fuel source is widely available I would like to lighten my load and get more use out of the fossil fuels i'm burning as opposed to save a dime or two vs. save a buck or two.

Then why do you drive a Jeep, and not, say, a Honda Insight or Toyota Prius? Considering the point you're making (repeated here for your convenience,) it's a valid question...

5-90

[Skullver]

This is getting out of hand, you will not save any mpg, there will be no environmental improvements, the only reason I even considered CF was because my buddies are trying to get started in the biz and it seems like a good way to CF my Jeepspeed rig to get free advertising, I am really not expecting to feel/notice a performance gain of any kind, that would be foolish. I think it would look neat and will be at least as durable as FG in the long run, I will leave the expenses to my buddies, they build it, I'll mount it. Good luck with your environmental crusade!

[RedHeep]

CF parts can be made durable, the aircraft I work on is 75% composite (including driveshafts), but those types of things are monitored at tight scheduled inspection intervals, have specific damage limits and the plane is $70 million a copy. I've seen and played a little with composite repair work (I'm not an airframer) and can tell you that it takes a lot of skill and the right equipment to get those parts right and repair them safely.

Our composite driveshafts have no damage limits, i.e. no damage at all, not even scratches.

Leave that stuff to applications that warrant it and people who know how to fix it.

[BrettM]

lighten the load and increase MPG ... they weigh less
I was just think gas is going up and the xj weighs a bit
well what about added horsepower ... ive had too much fiberglass break on me and it's expensive as well
I think it's ugly ... I was mainly just looking for a way to lighten up my jeep
to counter that with lighter other things
it will help the environment

So.... why do you want carbon fiber? your answers keep changing and they are all completely impractical.

[Lawn Cher']

If you are really concered about the enviroment, why are you driving a jeep?

x2

Even if you traded in your lifted jeep on big tires right this moment for a VW Beetle TDI running biodiesel, your contribution towards reducing the burning of fossil fuels is a drop in the proverbial bucket.

[dzolcali]

I think it's hilarious that i make a "statement" and then a lot of you come in with like argument...lol it's really quite funny that you can't just read something like "It would be cool to have carbon fiber on my jeep" and then you go all ballistic with arguments and dissing. I want carbon fiber on my jeep cause I want it on my jeep I don't have to justify it to some retard online...I think the carbon fiber drive shaft could be good for a lift because it could flex more and I was also thinking maybe some sorta alluminum shaft to cover it so it doesn't get gouged out on rocks incase I did want to crawl the jeep.

[5-90]

I think it's hilarious that i make a "statement" and then a lot of you come in with like argument...lol it's really quite funny that you can't just read something like "It would be cool to have carbon fiber on my jeep" and then you go all ballistic with arguments and dissing. I want carbon fiber on my jeep cause I want it on my jeep I don't have to justify it to some retard online...I think the carbon fiber drive shaft could be good for a lift because it could flex more and I was also thinking maybe some sorta alluminum shaft to cover it so it doesn't get gouged out on rocks incase I did want to crawl the jeep.

Actually, you'd find that CF would flex rather less than metal, rather than more. CF isn't "plastic" in the engineering sense - you'll already have a torsional load on it, and bending it between the ends would cause more trouble.

You might be able to get away with a set of bearings and a sleeve (kinda like the new Tom Woods? shaft?) - the sleeve would not be a bearing member for stress, which would allow it to protect the driveshaft more. However, you'll find you're going to be behind on weight doing that...

Until someone can come up with decent layup patterns, the "cool" factor is probably going to be seriously offset by the "cost" factor - again, I'm not trying to dissuade you (do it if you really want to!) but I'm just trying to give you some idea what you'll be in for...

5-90

[BlueCuda]

I have seen some drag cars run a CF shaft before with no trouble. I have also seen a CF shaft break on the starting line as well. Oddly enough it was stuffed with newspaper, made a hell of a mess. Alot of later model chevy trucks have a composite DS as well.

[dzolcali]

yeah I understand. I thought carbon fiber was stronger than steel...and I also thought that it flexed more similar to titanium, and as stated before the shrapnel from the busted drive shaft has less inertia making it somewhat safer to run. and I really think some thickly layered carbon fiber could be lighter than steel. Hrmm I think I may just make a super list and post it on jeep forum.

[5-90]

There's nothing intrinsically wrong with the idea - but when you select an engineering material, just remember that strength is not the only consideration - you must take the operating environment into as well... CF may make a decent driveshaft, but it will want to work in a "clean" environment - take into account all stresses involved...

5-90

[BrettM]

..lol it's really quite funny that you can't just read something like "It would be cool to have carbon fiber on my jeep" and then you go all ballistic with arguments and dissing. I want carbon fiber on my jeep cause I want it on my jeep I don't have to justify it to some retard online...

really?

i said:
admit it, you want carbon fiber because you think it's "cool". the sooner you admit it, the sooner we can get on with a (half)serious discussion about how to make some.

to which you replied:
carbon fiber isn't really cool. I think it's ugly, and all the ones i see on peoples hoods are chipped up or sun faded. I was mainly just looking for a way to lighten up my jeep ... blah blah blah


you sound like a freaking politician


this is just laughable:
I think the carbon fiber drive shaft could be good for a lift because it could flex more and I was also thinking maybe some sorta alluminum shaft to cover it so it doesn't get gouged out on rocks incase I did want to crawl the jeep.

and also contains even more flip flopping:
Perhaps for off road it is dumb, but I never specified an off road jeep cf driveshaft

[dzolcali]

those were posted out of order to support your point...way to go!

exceptions, what are you trying to prove brett, steel is superior to carbon fiber..? I mean seriously what do you hate about cf?

[BrettM]

those were posted out of order to support your point...way to go!

exceptions, what are you trying to prove brett, steel is superior to carbon fiber..? I mean seriously what do you hate about cf?
there is a logical order to those quotes, but the point is the same regardless; you are completely inconsistant and therefore no one hear can take you seriouslyv

[dzolcali]

there is a logical order to those quotes, but the point is the same regardless; you are completely inconsistant and therefore no one hear can take you seriouslyv

no one "here?" or hear...consistant with what? follow up with some explanation...it's not the whole "taking seriously" thing it's the someone makes a post to generate some conversation and diverse opinions and then you get, conflicting opinions that are not just stated they are very aggressive in nature for no apparent reason and almost attacking...so far 5-90 and a few others have been the only decent posting people I have read in my threads the rest of the post sound like 10 year olds that are fighting over some candy.

[Lawn Cher']

...the rest of the post sound like 10 year olds that are fighting over some candy.

I like candy. GIMME GIMME

[Lawn Cher']

what are you trying to prove, steel is superior to carbon fiber?

It depends on the application. You can't just make an absolute statement that one material is better.

[Michaelarchangelo]

Didn't the 03 Cobra come with a CF driveshaft? I do know you can buy them for stangs and such for about ~$500-600, but I can think of a lot of better ways to spend that kind of cash, like at a strip club.

[BrettM]

no one "here?" or hear...consistant with what? follow up with some explanation...it's not the whole "taking seriously" thing it's the someone makes a post to generate some conversation and diverse opinions and then you get, conflicting opinions that are not just stated they are very aggressive in nature for no apparent reason and almost attacking...so far 5-90 and a few others have been the only decent posting people I have read in my threads the rest of the post sound like 10 year olds that are fighting over some candy.
my mistake, i havent een speaking to your level.



you are a doo-doo head.


better?

:confused1

[MogifiedXJ]

STOP FEEDING THE TROLL!!!

[BrettM]

STOP FEEDING THE TROLL!!!
aw, but i'm still having fun test driving the new 'tard

[MogifiedXJ]

aw, but i'm still having fun test driving the new 'tard
http://www.fishtheoutdoors.com/images/photos/reel_schematics.gif

Alright...have fun

[dzolcali]

you guys are fascinated by trolls....takes one to know one comes to mind and last time I checked that phrase still holds true :)

also copied from the forum sticky

This forum has been created for people to discuss modification and tuning issues related to street XJ's.

This may include lowering XJ's, or just performance tuning a stock suspension XJ and more.

IF you do not care for this type of modification, that is fine. Bashing or rude comments towards posters will not be tolerated.

As always, the "Report This Post" feature is the best way to deal with a post that is out of line.

Enjoy the forum!

maybe i'm not in the wrong afterall since everything started out fine until someone was bashing and making rude comments...grow up plz ;)

[TheWarWagon]

How has this thread not been thrown into the abyss yet?

[streetpirate]

because its still fun.

[dzolcali]

i guess anything i post from now on is going to get the buttpirate attack with all the scurvey S cum and semen that follow em around. So yeah it's still fun.

[2001XJeep]

Has anyone tried converting their rig to biodiesel? I think it would be pretty neat to do that but I am unsure of the consequential attributes of running biodiesel, I.E. locating fuel, power loss or gain? Fuel economy loss or gain?
any information into converting the I6 to biodiesel would be helpful.

thanks

I've been quietly following along this amusing thread, getting a good laugh along the way, when it finally struck me that you're the guy with the biodiesel guestion. Man, this just gets better and better. No offense, seriously, we've all gotta learn along the way.

[shortxjdoug]

when it finally struck me that you're the guy with the biodiesel guestion.
he's also the guy with the electric supercharger
http://www.naxja.org/forum/showthread.php?t=94090&highlight=the+goods

[dzolcali]

good call....I do/did have an electric super charger, I took it off, noticed a acceleration drop actually...mpg drop as well...kinda funny how people think they are bunk but from honest opinion it was working ok on my ride...i'm just too lazy to put it back on and the wire tha tpowered it goes to my amplifier now...ah well.
the biodiesel thing...some guy at my work was telling me that there are kids in college that were converting their hondas to biodiesel with some regular home depot stuff...I don't think he was trying to sucker me, but perhaps he was suckered with that, and then passed it on to me and because i work with him I believed it. Oh well...
ima stand my ground with the carbon fiber, it's a street performance thread, which means STREET not offroad so those who keep saying "You can't hit a rock with that" obviously you haven't realized that rocks aren't on highways and streets that are going to crash into my drive shaft...so I stand firm on my original CF statements.

[MogifiedXJ]

Just curious you never did say how many cfm that electric "supercharger" flows. Do you know or can you find out? Seat of the butt dynos aren't very accuarate. If it doesn't flow anymore than 275cfm all it could do is hinder your engine.

[Beej]

I don't think its advisable to try to convert a regular 4.0 to a diesel engine. Better to just start with a diesel engine to begin with and then run biodiesel in it. Jetta TDI's have a nice diesel, but I don't know how easy a swap would be. There is another thread on diesels in off-topic, and Lawn Cher' is knowledgable about diesels and biodiesel. Search some of his threads on diesels in a cherokee...

I say go for it on the carbon fibre stuff and prove the naysayers wrong. Although using foamboard and fibreglass is also very lightweight and mocks up easily...

[streetpirate]

how many pounds of bost did that supercharger give you?

im thinking about getting one instead of the eaton blower, sooo much cheaper and i read on the internet you can get 100hp using old vacume cleaner parts!

[Michaelarchangelo]

The costs of making cf parts outweighs the benifits. If you are going to make a cf driveshaft, you only will get maybe a 5% gain in performance. It will cost close to $1000 just to get one made. I can think of better ways to spend that kind of cash.

[dzolcali]

sure...understandable. I'm not sure about the cfm of the electric charger and I know butt dynos are innaccurate...but I have noticed i have to stomp on the gas pedal a bit more to get the same power...that was very noticible almost instantly after I took the ESC off. Oh well...anyone ever drink TeQuizA...first time drinking it and it's not too bad really...

[streetpirate]

on a serious note:

possibly the esc that he used pushed enough air to make the throttle respond better?

[Michaelarchangelo]

I don't see how. That kind of fan has no way of keeping a positive displacement in the intake tract.