what clutch to run for over 450 rwhp?
 

I am lookin on finally putting my car together im sold on act i want a xtreme but there are 6 version s im shootin looking for 550 rwhp , gt40r kit what kit should I run? who is the best vendor thanks

i would use a factory presure plate with a six puck spring loaded disk.
it gives a smooth shift that grips just as well as a dual disk clutch and without notchy shifting into each gear.
that's my experience.

I dont think the factory pressure plate will hold near that power...

You are most likely going to want a twin plate clutch if you plan to drive it on the streets.

A factory pressure plate WILL NOT hold. The most cost effective combo would be something like an act extreme pressure plate with a sprung 6 puck disk or a spec stage 3 kit. However both of these are somewhat annoying on the street and tear up flywheels pretty fast. If you can afford it and want smoother engagement and a lighter pedal, I would go with an exeddy twin plate.

excedy for sure with that much hp. Especially for a street car.

A factory presure WILL HOLD. I'm using it.
if you measure the ACT presure plate spring, presure springs ARE the same exact measurements as the FACTORY one. so why pay more for the same presure plate.
moreover, correct the sprung six puck disk is good but still tear up the flywheel.

the twin plate is GREAT for holding HP but, the shifting into each gear is NOT smooth compared to stock.{i've used it }

Which act pressure plate are you comparing to? Not the extreme im sure...

the factory pull type that is painted YELLOW.
if you look very carefully, on the pressure plate, there are spots where #s & logo are grinded off. match up a factory plate you'll see it.

Well not exactly....

If you put them [pressure plates] in a press and measure the actual load the factory plate isn't even close to either of the ACT plates (HD or Extreme).

The diaphram may look the same but there are other differences that aren't so obvious that include the material and temper of the diaphram.

The factory plate is aprox 1600 psi, the act HD is about 2200, and the extreme is about 3000 psi.... these are actual numbers from plates I tested personally. Both of the ACT plates that I have look similar, if not the same, as the stocker... the difference is in the materials.

well, putting a pull type pressure plate on a push press is not testing it correctly.
how about testing the pressure in pullng a stiffer spring with the same linkage used?
do you really think that a snap ring can hold 2200 or even 3000 #s ?
I'm talking about PULL TYPE PRESSURE PLATE.

factory disk and pressure plate are made by DAIKIN which is DK with a wing logo.
ACT pressure plate is made by DAIKIN which is DK. it's wing logo is grinded off and painted YELLOW with ACT sticker.

i am in complete agreement w posts 3,4,5,6 & 10.

IF you really plan to be making 550 rwhp save yourself a whole lot of time and money and buy the right clutch FIRST.

the exedy hyper twin cerametallic. ZM022HD.

and here's where to buy it... PM

as to posts 2,7,9 & 11...

you are saying the factory Daikin pressure plate will hold 550 rwhp in an FD? the factory PP has 1600 pounds of springs. the ACT HD PP is up 40% from that and the XTR is up 59%. they are NOT the same spring pressure. as to whether a retaining pop ring can hold a 3000 pound force. of course it can. Daikin holds the patent on it (or did until it expired Jan 1 07) and it is in shear so no problem.

FWIW, i ran a exedy hyper single which had 2655 clamp force w a 6 puck cerametallic disc and it couldn't hold 500 rwhp. so i doubt your 1600 clamp force PP has a chance.

so poster number one, if you really plan on making 500+ rwhp bite the bullet and buy just one clutch package not two. BTW, since you get double the frictional area w a double disc you only need 2205 clamp force so you will enjoy driving your car on the street.

howard coleman

im planning for the network of 500whp... i ended up getting the act hdr6. its pretty streatable. it holds for that network of power. twin plate clutch might be a bit for the street IMO. you need to figure if its a street car or a drag car.

ACT has three types of pressure plate series. HD, XT, and XX. i have not used the xt but you might want to try it as it shouldnt be much worse than i have. as i stated the hd to me feels pretty good. Chatters sometimes if you go idle in 1st gear driving. but as long as you stay on the throttle its all good. i truely love it the thing is honestly so touchy... its and "on and off" switch.

Figure out your destination out and let us know...

Thank you Howard. I get so sick of bs info being thrown around like its factual.

There are a lot of cars out there with a Mazda logo on them, that doesn't make them the same.

For those of you who tested pressure plates, what setup did you use, and what amount of travel (compression) is the force measured at?

Dave

Spring pressure is spring pressure, whether you pull on it or push on it.

at about 420 WHP, mine holds up fine. im not sure about 550 whp though. I would go with the Exedy twin plate.