20B clutches
 

Stockpiling parts for the 20B conversion on my FD. I have the engine, ECU, subframe already. Wondering what clutch system to use to harness the torque and hp. For those who have the conversion done on an FD, what has been working well for you or not working well. I'm wondering about an Excedy dual plate clutch option. I want to keep this streetable.

Thanks,
Aaron

Can't speak from an FD point of view but from driving my silvia, there isn't too much difference between a twin and a triple plate clutch. Drivability wise anyways.

-Destin

street... keep the boost low ,use light use of the throttle and get a sprung 6 puck and a PP that is NOT so extreme. Not looking for a work out are we? If its a street car you will not be pushing 500+hp all the time of even a 3rd of the time you drive.

BTW sillbeer you have a type-o in your signature " 20B FC, T88-34D, Motec M8, dyno'd 587.4rwhp and 64.4rwtq @1.25" no way you have 64.4 FT/LBS OF TORQUE

I suggest the Exedy Twin Plate I like the feel and it's just alittle stiff than stock to me

I have a Tilton Twin ceramic disk clutch. It's a little tough getting use to, If i was goint to buyanother I'd go Exedy twin or tripple. They also offer carbon multidisk clutches also.

Um, be careful...
I only know of OS Giken stuff, and the offer a "street" twin.
This set-up is so tame, you won't even know it's a $1,000+ clutch in there.

As for the OS Giken triple, we run one on our race car, and that bitch is brutal.
Worst than any single-disc, puck style disc I've even seen.
Engagement is brutal, and with the light flywheel, it's not even close to be be streetable.

Mind you, I call an ACT 6-puck, unsprung center a "streetable" clutch. :)


-Ted

i have an OS twin, is the street one sprung or not? I'm putting everything back together on monday so i'll prob share my opinion after that. Anyway to know what i have in terms of "race" vs "street"

If I remember correctly, it isn't sprung.
The way to tell is to look at the flywheel.
Does it have a lot of holes by the ring gear?
If it doesn't, it's a street version.
If it does, it's an ultra-light flywheel and designed for race.


-Ted

ATS Twin disk Carbon - holds 900HP, and ATS Triple Carbon Disk - 1500HP.

FULLY STreetable ( we run teh triples in our Evo8,a nd in a Supra), and we have numerous customers with twins.

We sell both of them:-)

George

PM'ed you Boost Solutions

I'm running a ORC Triple with a unsprung hub on my 20B and I love it.. Softer pedal feel than the OS, but 1100kg's of clamping force.. Once broken it it engages smooth for a multi plated clutch and drives very well and there is no way in hell it'll even think about slipping.

yeah i too have to decide on a clutch/flywheel setup for my 20b . i was just going to get an ACT street clutch for now... but maybe i should just go for one of the twins while im spending $$$. by the way, what do the FW's weigh on some of the twin disk setups? at this point im thinking about getting a racing beat 17 lb wheel, unless you guys can recomend something better for my application. (i was thinking about the 9.5lb wheel as well, but some of the knoledgable 13B guys recomended the heavier one). oh yeah, mines a (well going to be) mainly a street car as well, but id like it to be track-able. -heath

Most, if not all, multi-disc clutch systems come with their own flywheels.
If you're serious about one of these clutch system, please do your research before dropping money for the RB lightened flywheel that you probably won't need in the end!


-Ted

no i know the multidisk clutches have their own flywheel that comes with it (i was just wondering what weight say the OS or exedy flywheels came in at). factoring in the price of a $300-400 FW + a $400-500 single clutch... it almost seems worth it to just get a twin plate to start. im just worried about drivability. id like to (and i use that loosely) be able to be stuck in traffic on the highway w/ the 20b (not that it would happen much) and be able to creep along like every other stick shift. infact with all the torque of the 20b, it would be a good traffic creeper since you could let the revs drop even lower. basically what im saying is that im trying to pick the most versatile clutch for every situation from track driving to sitting in traffic. while i know you cant have your cake and eat it too, i know that some clutch setups are better comprimizes than others..... im just trying to see what everyone thinks would be the best compromize. as of now, if i had to place an order today i would just get a RB 17lb FW and an ACT street/strip (simply for not knowing what might be better suited for what im trying to do).

ok well i looked up some more info about the exedy twin plate clutch...its sounds basically streetable from the description. twin plates, a single springed hub bor both plates, something about a "clean" disengage as both plates are engenered to release at the same time. it comes with a crommolly FW (im wondering what that weighs?). also, if anyone knows... does the clutch remain as a pull type for the FD with the exedy twin? im told that with the OS it is converted to a pull type. im really liking the sound of this exedy unit.... i just wonder if the discs are individually replaceable or if you have to buy a new one when its dead? also, apparantly it has some "chatter" on cold low RPM startups, apparantly due to the material used for the discs

The last thing I would worry about is the flywheel weight, most of the aftermarket twin and triple plates are designed for circuit racing and are a good mid weight that will work well for any type of driving. It's the if it's going to hold the torq of a 20B and not slip yet at the same time engage smoothly and not torq shock the transmission in to breaking off a input shaft that you should worry about

To me the Exedy is more streetable than say a 6 puck sprung clutch, If I'm not mistaken you can replace the individual disks, I spoke with the Exedy sales rep @ the D1 DRIFT @ Road Atlanta and it is a push pull type just like stock, i don't know about the cold low rpm startups since it is still summer time

I have looked at the Exedy twins, but I could never find out what the torque ratings were on them. I abuse clutches and I would hate to spend 1k+ on a clutch that will not hold up. Right now I am runing a unsprung 6 puck ACT on 13bt and its holding. But, the debate, is if it will hold on my 20B FD project.

im finding that out for us
i have the act 6 puck and prolite flywheel for my setup.
best part is if it doesnt hold ACT will replace it!!!
give me two months and i'll have some answers about this setup

should hold "567 ft/lbs"
so.. 700hp? figuring if i hit 700hp the torque will be somewhere arould 600ft/lbs

FI: that is for the exedy-twin or the ACT setup?

ill most likely be placing an order for the exedy twin plate... i like the sounds of it, so maybe ill just go for it.

I was told by the Exedy rep that it's good for 600lb/ft of torque

The RX7.com site sells the Exedy twin plate clutch set-up for $1550. Their quoting 500+ torque hold and 700+ HP easily on their site for this set-up. I think I'm leaning towards this option too.

??? I know some of you use a different tranny than the stock FD or TII. So how are you purchasing the clutch for it? Are you getting a FD clutch? How hard is it to match that up with a different tranny?

Sorry. The concept of trading parts like this confuses me.

I'm also interested to know what clutch to use with an other than rx7 tranny. I was thinking a turbo 350 tranny or something. Not sure though. I know the stock tranny won't hold for long though. I'll be running some thick redline or something in it to try and save it as long as possible though.


-Destin

That is why I orginally picked a tilton. I could parts and different discs to suit different trannies w/o special ordering them.
The tilton does grab hard though. I am in the middle of changing the pressure plate to a longer throw one with a stiffer spring increasing the holding power to 820 lbs/ ft from 620. I am hopeing that the longer throw will aid in slipping the clutch from a start.

A turbo 350 is an automatic tranny, there is kits to bolt it to the rotary.