Pros & cons of kevlar or brass for clutch application

[J.R. Adkins]

What are the qualitys and drawbacks of each?

Lifespan?

Holding power?

Peddal feel?

Cost?

Special machine work?



These are just a few things that I can think of right now!

I know that most of you HIGH HP guys have thought of this.





Thanks,

J. R.

 

[FL70CAT]

Brass is very tacky and will hold alot of power.

I think the kevlar can be melted if heated up too much??

 

[SLang]

Kevlar:



1) Hold about the same power as organic (factory)

2) Last 2-3 time longer then other clutch material

3) If you "smoke" your clutch, after a cool down the Kevlar will not be affected

4) Kevlar will not damage you flywheel of pressure plate

5) Relatively cheap, actually less than a stock clutch

6) Feels almost identical to stock

7) Can be slipped easily for backing and heavy trailering



I've seen a couple Antique Tractors hook 70-80 times per season and the clutch look new. No damage to anything.



Brass:



1) Hold a lot of power. Look at Joe D. 's clutch

2) Will last longer then stock if in a stock truck, but why would you need one in a stock truck

3) If you "smoke" your clutch, the brass will slip. You can take it apart and refinish the brass (I was told) but why the flywheel will be junk

4) To much slipping or over time will damage flywheel and pressure plate

5) Pricy compared to stock

6) Will not feel like stock. Will be a bit "grabby"

7) Hard to slip for backing and heavy trailoring



Joe D. (I'm not picking just repeating what I was told) siad his clutch could be used for controlled backing but only if you keep the RPM's up above 1200.



Stock replacement or slightly more then stock the Kevlar is the way to go. If you are pushing some power then you'll have to find the clutch you like.



Scott

 

[South Bend Clutch]

Paintersdsl,



We have been using the kevlar material in clutches for 20 years. All I can say about kevlar is that IT IS AWESOME!



SLang gave a very good description of the features between the two but the one thing that we have found over the years that contradicts something that he said with heat and kevlar. Kevlar has a fantastic ability to NOT create heat but if it does get super slipped, to the point that high temperature is created, kevlar will, in fact, turn to ash.



The great features of kevlar, like he stated, does not cause grooving like the metalic does and the durability of the material keeps the wear factor down which enables the clutch to last 3 to 5 times longer than other materials. Kevlar, however, if it is a true, 100% kevlar, patented by a company named Tribco, is NOT inexpensive. It can cost, in comparison to other materials, 8 times as much. But understand, that is only one piece of the clutch. For what it does with the life extension, it is an inexpensive way of putting a quality clutch in your vehicle.



For the Dodges, our first designs of clutches were using the kevlar material. One thing that is required to make it work well is a higher clamp load of the pressure plate, but when you're dealing with the kind of torque numbers that so many of you are accomplishing, we could not get enough plate-load coupled with the kevlar to hold. That is why most of the clutch companies are not offering kevlar for your dodges. I do however use it in semi's, agriculteral, passenger cars and mid-sized trucks, with great success.



A good way to look at what your dodges are doing, when you have 500 horse in a passenger car you are probably creating 350 ft. lbs. of torque. When you have 500 horse in your dodge diesel you are creating over 1000 ft. lbs. of torque. If you are not planning on taking your truck much over stock I would highly recommend a kevlar material but make sure, where ever you get it, that they are using Tribco's clutchtex material. Other companies offer kevlar facings but they are only a small percent of kevlar, approximately 5%, coupled with a paper-like material. Example: fibertough, made by SK Wellman. Buyer beware.



Peter

 

[J.R. Adkins]

Road trip

Well it looks like i will be making a road trip tomorrow! I drove down and talked to a diesel performance co. in Columbus, IN today about their clutch. They are not willing to back up their product if it breaks! Whats up with that? So it looks like I will be going to see the fellas at SOUTH BEND CLUTCH tomorrow. Can you say ROAD TRIP! Ok, OK so its only a short one!



P. S. Peter, your guy Eddie realy KNOWS his stuff. Looks like it is RASE TIME!Oo. See you tomorrow Peter.