PM Sent in response to your question to me.......
Clutches are a personal preference kind of thing. As you found out, if you ask 20 people for recommendations, you're going to get 20 different answers.
As far as which one is best, there truly is no way to answer that. What's best for a stock, un-modded daily driver is not going to be the same as what's best for the slightly modded or then again, the full blown drag racer, there simply isn't 1 clutch that works best in all situations.
The biggest and most important question I need answered from you is what flywheel are you using? Back in the days of the classic mustang, the flywheels were only drilled for the Borg & Beck type, 3 finger pressure plate (I'll explain that in a minute). Nowadays, modern cars use a diaphram style pressure plate and the 2 bolt patterns for them on the flywheel are not interchangeable.
As I mentioned, back in the days of the classic
stang, Borg & Beck style clutches were what was used. The pressure plates had 3 large fingers that the throw out bearing contacted to release the disc. These B & B style covers are notoriously hard as far as pedal effort. To overcome the hard pedal effort the factory installed what is called an over center spring on the top of the clutch pedal, up under the dash. Contrary to popular belief, this over center spring actually assisted in depressing the clutch pedal. The mis-conception is that the over center spring was there to pull the clutch pedal back up off the floor...that is not correct.
The diaphram type clutches that is used in modern cars is different in that instead of 3 large fingers on the cover, they use 20 or so smaller fingers. The pedal effort was one of the main reasons for the switch. Diaphram type pressure plates are easy on the leg when it comes to pedal effort.
Discs come in a wide variety of compounds. The most common is copper organic. This is the material used in OEM cars and alot of aftermarket clutches. They wear really well and last a long time. They are not prone to chatter and can withstand a decent amount of power. The next step up from organic, would be Kevlar. Kevlar obviously is stronger than organic so it can withstand more power. They wear good, although not as good as organic. They are not prone to chatter, but some can. From there you move up to a mix of Dual friction, Carbon-Kevlar, Carbon-metallic and Ceramic. Dual friction is made so that 1 side of the disc is usually organic and the other side is usually either Carbon-Kevlar, Carbon-metallic or Ceramic. The high torque rated clutches (racing type clutches) are usually either Carbon-metallic or ceramic.
The pilot bearing is not as complicated. In the '60's and 70's a bronze or brass bushing was the norm. Modern cars started going with an actual bearing. The reason being is the improvement of the transmissions. The toploader 4 speeds from back in day weren't built to such tight tolerances as todays modern 5 speeds. An easy example of this would be to grab hold of the input shaft on a toploader, muncie or A833 and you can see how much play, or slop is in the input shaft. They move around quite a bit. Modern 5 speeds, like the T5 or the TKO have virtually no movement at all. A bushing tends to "waller" out over time, thus allowing for more movement of the input shaft whereas a bearing will not "waller" out and will stay true for the life of the bearing.
So, now that my little history lesson is done,
, to answer your question, I really would like to know what you're doing for flywheel?
If you have a flywheel that has the diaphram style bolt pattern it, I would highly recommend a OEM type diaphram style clutch with an organic disc (based on your description of what you have). As for brand, well, there again, 20 different opinions are going to come into play. An OEM brand like Valeo, Luk, or Sachs is very easy pedal effort and will last a long time, assuming you setup the throw out bearing adjustment correctly. If you want to go with something that'll withstand a little more power than stock, in the event that you upgrade the motor down the road, I would recommend Spec. It is what I run in my daily driver.
Let me know if you have any more specific questions.
Richard
Tech Support
Tremec TKO, T45 & T56 Transmission Systems
Whats the best clutch kit for my Mustang 
(thanks 2 IhaveadopeGT)
