Need help selecting Exedy Twin or Triple disc clutch
 

I'm about to pick up a clutch for the race car and i dont understand much about the twin and triple disc setups.

I will be using my car for mostly street racing and some drag (very light).
I know this, I want OEM pedal pressure and able to hold a ton of power (over 700rw). Price isn't much of an issue (would like to stay under $2,500 +/-).
So far, seems triple disc is what - i understand it'll hold more torque without slipping.

I've looked at the Carbon-R triple from exedy and i think this is what i'd like.
- Disc's are tougher, lasts twice as long.
- Stock pedal pressure
- Hold ton-o-power ;]


Any info to guide me would be! Thanks!

Multi disks are not meant for drag racing.

No matter what anyone says, any triple disc is NOT streetable...

700rwhp?
What ya got that's making so much power?


-Ted

I'm running T88h for now, in the future i'd like to step up to a big T51R-SPL.

If the triple-disc clutch is not meant for drag racing - What should I be looking at for street / strip racing?

Depending on your HP and amount of street driving you plan on doing your clutch needs vary. Now these are some ACT clutches, I use the 6 unsprung with good results. Some prefer the Spec clutches over ACT. and you also have options on P Plate some say use the exteme, others say just the heavy duty.

Here are some of your options:

6 Puck un-sprung- Hard to drive on street but not impossible
http://www.rx7store.net/product_p/zx3-xtr6.htm

4 Puck un-sprung- Very hard to drive on street
http://www.rx7store.net/product_p/zx3-hdr4.htm

6 Puck Sprung- Probally the best option for both worlds, but it is relativly new and untested for higher HP.
Http://www.rx7store.net/product_p/zx3-hdg6.htm

And like Ted asked where is 700 hp coming from?

I dont want any increased pedal pressure.

What you got a wooden leg? Then what do you need 700hp for? This isn't a stock car anymore, you have to give and take at this level of the game. I would love my A/C back, but you know what it isn't going to happen.
I gave you some great options that are realistic. I use the ACT 6 puck with a HD P-plate. It sis stiff but not too stiff.

Ive drove a few cars with 4pucks as well as a triple plate, I would recommend triple over the 4 puck anyday..

The Comp R clutches are geared toward road racing. They use smaller diameter disks with a lighter flywheel than the other Exedy multiplate clutches, so you might be better off with their standard triple disk clutch. You should also check out the Carbonetics stuff. They make a twin and triple disk carbon setup for our car and they are available with a few options, including a stiffer pressure plate.

You don't want a flywheel under 12lbs for drag racing either. I have spoke with Exedy Tech, and flat out said there multi-disks are not made for drag racing. The problem with high HP is you need a strong PP to hold it.

Makes sense - I dont drag-race at all; light means maybe one pass a year?
..but that is really good info that i overlooked. helps in the decision! ;]

In your first post you called it "your race car" that is used for street racing and some light drag.
What will the car be used for, and what turbo do you have out of curiosity?

I'm currently on a T88h, I'm changing to t51r flange GT42 or something (haven't started comparing compressor maps yet) in that wheel size. Who knows what i'll end up with, however, i dont know what the current turbo would even max at(?).

The setup now is street/strip but i rarely hit the strip. I got too jumpy and never did well launching the car. Overall, its stays on the street (when its running).

Triple Carbon it is! FDNewb has helped me select a clutch.
Bless that man!

Damn it! ...missed the edit-window;


Exedy got back with me today about the car... Here is their response


Well hrm, glad i asked; :wallbash:

Ted, I saw this post while searching for somethin else, and just wanted to comment that I spoke w/ Tilton, and they assured me their triple plate carbon clutches were VERY streetable, w/ the smoothest engagement. Care to comment?

~Ramy

Oh, you're cheating now. :)

Carbon clutches is something of a secret when it comes to trying to keep the car streetable.
The "affordable" multi-disc carbon clutch is something of a recent phenomenon.

We run an ATS twin carbon on our 20B FC.
Does that say enough? :)


-Ted

the fundamental problem w the rotary and clutches is that due to the compact size of the motor mazda elected to use a smallish flywheel. that really decreases our options. most of the v8 guys can run simple clutch packages because they have so much frictional surface.

we don't.

you will need at least a double disc to deliver more frictional surface so you don't have to rely on huge spring pressure like the single discs...

i love exedy and have posted many times about their products.

i also love cerametallic v carbon-metal.

carbon-metal (that's a carbon disc and metal flywheel and floater plate) has a frictional coefficient that varies between .29 and .48. cerametallic is .49 all the time. carbon-carbon does not have this variance and is generally available from tilton for lots of bucks.... maybe $4000 or so as i recall.

you don't need carbon... Exedy's cerametallic is a patented material and works magnificently.

i run a twin sprung cerametallic (ZM022SD) and the pedal effort is close to stock. i believe the torque rating for the twin, which is invisable as to driving effort and manners, is just north of 500 foot pounds at the rear wheels.

i have run exedy cerametallic clutches for 3 years. i originally had the Hyper Single cerametallic and after 1.5 years upgraded for more capacity.

i measured the friction thickness of the disc when i sold it.

stock was 4.6 MM. it was 4.58-4.59 MM. hardly any wear...

Carbonetic was mentioned.. they only have a push clutch for the FD which requires a convertor. no thanks.

Exedy Cerametallic in double or triple w springs gets my vote.

good luck,

howard coleman

LOL. My bad hehe.

And I feel you on "affordable." The Tilton triple carbon-carbon is indeed like $4K as Howard mentioned. But DAMN she's a sweet clutch hehe :D

Oh and Howard, I don't doubt your analysis for a second. Only reason I mention a carbon triple is because some guys on here are either already running or currently building 700 - 800+ hp FDs, and with that kind of torque, you'd be putting a twin plate to the limit; not much wiggle room. So naturally the smart & reliable thing to do is go triple. And when stuck in the "triple zone," carbon-carbon is the only way you're gonna be able to engage that thing w/o riding like crazy or stalling out all over the place and making driving your car unbearable.

~Ramy

i received a PM asking a couple of Exedy questions and thought the info might be of general interest...


pedal pressure:

meaningful for 2 reasons.

1. leg fatigue... leads to taking the daily driver more often.

2. high spring pressure has caused many an FD clutch actuating arm to break. don't ask me how i know:)

pedal pressure can be equated w clamp load or spring pressure.

FD OEM 1600 lbs.
exedy hyper single spring pressure is 2655 lbs.
exedy twins 2205 lbs. (more frictional area allows less spring pressure... win win)
exedy triple 2430 lbs...

i was comfortable w my hyper single but do appreciate the significantly less spring pressure of the twin.

Exedy torque capacity at the rear wheels:

exedy hyper single 395 road racing 340 drag racing
exedy twin cerametallic 600 road racing 518 drag racing
exedy twin carbon/metal 578 road racing 501 drag racing
exedy triple carbon/metal 871 road racing 756 drag racing

howard coleman

Howard, I thought Exedy's official position was that they don't make clutches for drag racing?

i have no idea what exedy's "official" position is on drag racing...

if you run in the 9s and 10s there are probably no streetable clutches that won't be a maintainence item, along w any other driveline part, so it wouldn't be irrational to hold such a position.

the torque figures in post 21 come directly from an Exedy internal document and were sent to me by the head Exedy tech guy in the U S.

i am a road racer and make no particular representations as to what works and doesn't in drag racing. the numbers were merely an FYI and do come from Exedy.

hc

I wanted to revisit this thread with some minor update...

I did end up with a T51R-SPL (GT4594LR) and a Triple Disc Exedy clutch. The clutch is VERY streetable. Allow me to explain why I *think* it's very streetable..

For my reference / comparison:
-ACT 6 puck (sprung)
-ACT 6 puck (unsprung) w/ x-lite flywheel (bad mistake)

Over all impressions:
The triple-disc setup didn't rattle/chatter (think Supra here) on my car... After getting use to the new feel of the pressure plate & disc-material, the clutch was streetable because i was able to adjust to the new feel. Yeah, it's an "on/off" - "in/out" clutch but it didn't take but a few mins to get use to it.

Now I'm glad I ended up with a heavier flywheel, as the idle was very smooth compared to the x-lite flywheel. Overall, it's working well;

Bringing this back from the depths.

Howard,

Did you have an issue where your hyper single couldn't keep up with your boost curve. I'm only putting down 300 rwt, but since my boost comes in so early in the rpm band my clutch is slipping badly. I have less than 4K miles on the clutch with only three competition events done so far.

I guess I will be upgrading soon. Either the Twin cerametallic or the twin carbon. :(

Anybody want to buy a slightly used Exedy Hyper single clutch?