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Kevlar Clutch........What's your view?

markaboo929 said:
can you relate stress and heat to what offroading does? then it makes sence.....to me anyways...........thats why I am me and not you:spin3:
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I probably have a better understanding of it than 98% of this board; but your page and a half paragraph still made no sense. :)
 
Just trying to inform others-be it make sense to some and not others.I could never imagine going to hi tech algebra or rocket sience classes or make sense of it,BUT to others it does.............:cool:
 
I mean, I wasn't trying to be a dick or anything; but its hard for someone to comprehend anything *remotely* technical (even when you already understand it) when you can't tell where one thought stops and another begins..
 
I get that way sometimes-not being able to actually say or write whats really on my mind.I didnt take it as bad at all.I did have to get rid of it becasue after I re-read it-what the hell was I thinging if Iwere someone else reading it? Thnkx-in a good way!!! I was trying to answer the reply in the above from the cost or benifit of this set up,some will some won't.I did get it free anyways hell free is free right?:thumbup:
If anyone has any questions or sugestions feel free to let me know.I need other input besides my own use and thoughts so I can relay it back to the company
 
My jeep is comprised almost entirly of free stuff (or so cheap it might have been free). You can't go wrong with it. :)
 
I would still like to know, if someone could summarize it quickly.

You don't have to tell me about kevlar, or the inherent benefits of cryo'd steel pieces. I work with powertrains on a daily basis, I'm a mechanical engineer & registered in the state of NJ, and I've done a lot of failure analysis and metallurgy studies when we get broken things back at our company.

That being said, all I'm asking is if my $180 clutch package functions fine for well over 100k miles, then what does this kevlar thing offer me? I understand the material benefits and the fact that it reduces heat buildup and the effects of said buildup...but at the same time, it seems to me to be a solution looking for a problem. Maybe it's a good investment because it's cheaper than regearing your rig so that a normal clutch works? I dunno.
 
This is more of an individual benefit thing,as you stated "me".Others may need more than stock cause of the way they may drive or use thier clutch when wheelin.Some may not need anything more than a stock clutch.I can say that if a stock clutch lasts you a long time then a Kevlar one will maybe last you forever.it really all depends on what you have on your particular set up,gears ,tires,type of terrain and how you drive,if your a heavy throttle person then a lot more stuff will break.if you can relate to some people that break stuff a lot and what they break to other people that do the same as the first person with the same running gear and do not a have single breakage,then you can see a benefit,or at least I can.I got this one as a free product to partisipate on some real world R & D ,i am trying to see the benifit as you are too.hell everytime I go by the place and stop in the manager keeps askin me are you ready to abuse the hell out if it yet? It is almost burnished in.in your reply about the stock one not slipping,it wont, it is not of the same material as the one i have,and the K one needs to be burnished in for it to perform as designed and will have slippage until the fibers have settled.I have 560 miles on it now and it only slips when I hammer on the throttle in 3rd gear-my torque load situtaion will be different from others-it slips for 50-100 rpms for a second and then grabs.Almost fully broken in.I posted this here only because I am a tester for this unit and all the feedback I recieve - good or bad -is what I need to relay to ZOOM.I do agree with you on thinking about it as a possible stupid alternative to gearing or what ever was on your mind ,but then again would you drive on 35's with 3.07 gears in an automatic trans? Sure it wont slip ,but sumtin will break for sure or overheat.33's and 4.10 gears by the way-no suk gearing here.
This was also an opertunity to post some more results as milage progresses
 
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Oof. I see why your original post was edited. :gag:

Anyway...I can snap front Dana 60 shafts on demand with the stock clutch. Below 3k RPM. Meanwhile I also broke Dana 30 u-joints on a reliable basis, just about every trip out. I'm not saying the kevlar clutch doesn't have its benefits...all I'm asking for is a reason to buy it over the stock clutch.

I would be happy to debate/discuss this with the guys who designed this thing. I'm sure it's a great product...but I don't see the need to have it if you haven't upgraded the motor at all.

For the record, no, I wouldn't drive 35's with 3.07's with an automatic trans...for several reasons. One, because then this discussion would be irrelevant, two, because that's a dumb ratio to begin with, and three, 33s and 4.10s is still under-par as far as the 4.0 motor is concerned.

Next?
 
If I may ask what gear ratio are you using with yer 39.5's.Does your 4.0 run the same as mine? Stock 4.0 ,not stroked?what rpm range do you keep your 4.0 at most of the time?where is the motors peak torque at?Is your 4.0 tunned in like mine?-for example is the timming advance electronically and progressively like mine?Is YOUR tail pipe color dark grey or is it all black and sooty?i could go on forever here ,but I wont.
Again, individual benefits.
 
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markaboo929 said:
If I may ask what gear ratio are you using with yer 39.5's.Does your 4.0 run the same as mine? Stock 4.0 ,not stroked?what rpm range do you keep your 4.0 at most of the time?where is the motors peak torque at?Is your 4.0 tunned in like mine?-for example is the timming advance electronically and progressively like mine?Is YOUR tail pipe color dark grey or is it all black and sooty?i could go on forever here ,but I wont.
Again, individual benefits.
Click to expand...

Gear ratio where?

On the street, 4.56s. Not low enough, but the transmission covers it because of the granny low gear. 5.38s would be ideal.

On the trail, crawl is 182:1, standard trail riding is around 84:1 or 67:1 depending on where I put it.

4.0 is dead stock with K&N intake, passes full emission inspection in NJ (which is a tailpipe sniffer and full exhaust gas analysis). I keep it running well. My tailpipe color is no color at all, like a properly tuned engine should be. On the trail I'm idling if I'm not bouncing off the rev limiter to get over something, and on the street I'll drive it up to 4500 RPM between shifts because the gearbox has such wide ratios. On the road I keep it between 2200 and 2800, unless I"m accelerating, in which case I'll shift to peg peak torque at around 3200 or a little higher. I would safely say that I'm putting out the correct amount of power that the stock motor is meant to do.

If yours is tuned or upgraded, then maybe there's the answer to my question, which I already said: the only reason I can see needing an upgraded clutch is if the motor is putting out more power than the stock clutch is designed for.

I'm not trying to diss the product, as I'm sure it's extremely well-designed and very high-quality. I'm just trying to find out, for the rest of us, what kind of benefit we can actually expect to see from this.
 
Well I can see that my gearing-for now-is quite adequite-NV3550 trans is what I run.I shift at 3000 mostly and I can keep up with traffic very well.my motor has been tweeked -free flowing air filter-larger exhaust -I can out accelerate a bone stock jeep with what I run,so my power output is above a stock motor-not much but more.Off road it has been fine for me I have no problems creeping over stuff at all,with out riding the clutch either,and road spped I keep it at 2500 rpms or so no matter what my speed is-i get 18 mpg this way,my jeep is way overwight from skidplates and suspention set up-TNT customs c4x4 bumpers-etc,....Eventually I am regearing and changing front axle,to 5.13s with 37 or smaller tires.Benefit , I can maybe see for some will be a VERY long lasting clutch-Kevlar outlasts OEM.Some one that runs it hard in the dessert like in JEEPSPEED events could possibly benifit from running a manual trans instead of an auto and not have heat issues with trans.People that live in more northern areas wont benift from heat properties.yeah it seems like a good product and I appreciate the feedback so I could help them with costs as well as what it can handle
 
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Here is an up-date.I am at the 900 mile mark,on Saturday I had it slip when it was hot while cruising in 3rd gear at 2500 rpm while I hammered the throttle and it slipped for 50-100 rpm for a split second.I drove it for a bit on Sunday and tried the same acceleration test,No problem all day,or any on my way to work this morning.Time to really test this clutch on the trail,it has finished it's "burnished" stage.:peace:
 
markaboo929 said:
Some one that runs it hard in the dessert like in JEEPSPEED events could possibly benifit from running a manual trans instead of an auto and not have heat issues with trans.People that live in more northern areas wont benift from heat properties.
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Ambient temperature isn't really the issue with heat build-up. To result in bluing like you had on your old clutch disc, the steel temperature was likely near 600* in that area. Regardless of whether you're in the desert or up north, the clutch itself is still strapped to a 210-degree engine block. The heat buildup in question is a result of slippage or overloading, not so much the temperature outside.
 
markaboo929 said:
Then why is'nt my flywheel discolored in that same are???????? hmm...........better think that reply again.:gag:
Click to expand...

No, not really. The same heat input to the flywheel and the clutch disc results in a much higher temperature increase to the clutch, because it has a lot less mass than the flywheel. It's also thinner so the heat flows better through it.

Your flywheel is strapped to the block? Weird. Last I checked, mine was bolted...however the clutch was just kinda held there by the tension of the fingers on the pressure plate. Either way, you're proving my point even more...so you're saying that the ambient temperature of the clutch disc will be even less than 210 degrees I guess.

I'm not trying to diss the product. I'm sure it's very high quality and good at what it does. I would just like some real reasons why it's worth the upgrade. There's a lot of aftermarket stuff for these trucks; some of it's worth the money, and some of it isn't, and it all depends on what you're using it for. That's all I'm trying to find out here.
 
Vetteboy when I typed "strapped to the block" it was YOUR reply in quotes see your reply.Plus the flywheel absorbs a lot of the heat from the block/crankshaft and most of the heat that gets transfered to the clutch hub is by way of the clutch material and the metal section that is between the center hub.If you notice in the stock clutch picture there are small sections where the center hub is joined to the outter section that the material is rivited to,and the kevlar replacement is actually solid,with that being said the stock clutch disc is blue from heat transfer and that is where the kevlar one comes in to play absorbing most of the heat that normally would go to the hub center and the inputshaft of the trans.Think about it for a minute.............yeah I know about the "made in china" deal but that is actually a center hub taken apart to modify it and add there outter metal section that is sandwitched in between the 100% Kevlar meterial they add.i was conserned too when I recieved the set.It would have been hilarious if the pilot bearing was in a fortune cookie!!!which was made in usa by the way and the clutch release bearing is a Mopar unit.:laugh3: And I learned that this is actually a GM/Chevrolet set up,direct bolt on, ment for racing which lives behind chevy small block v8's that have been modified,so clamp pressure is more than adequite for the 4.0.:cool:
 
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