What clutch for an EJ20T with a non turbo gearbox

Gannon · Post by **Gannon** » Wed Jun 23, 2010 7:37 pm

I have started collecting parts for my RX. The EJ20G, DR AWD gearbox and the crossbred kit are all in my shed.

I chose the DR gearbox (from a Gen1 GX) because i wanted to keep it dual range, and because having a cable clutch seemed easier than fitting a hydraulic setup

My issue is the clutch, what do i use.

According to the FSM, the non turbo clutch has a clamping force of 450kg, turbo is 620kg.

I priced an NA Exedy clutch at $347 on ebay (I believe Subaru use Exedy clutches)
Repco wants $540 for a HD clutch (apparently has 35% more clamping force than the standard item)

So that means that 450 x 135% = 608kg

But is it actually as good as the factory turbo clutch? or is it just a tad better than the Exedy NA clutch

Do i need an NA flywheel or will the NA clutch work with the turbo flywheel?
if i punch out the dowels and redrill holes for new ones to suit the NA clutch

Any information or discussion is welcome

AndrewT · Post by **AndrewT** » Wed Jun 23, 2010 8:44 pm

use the standard push clutch setup which matches the gearbox (flywheel, clutch disc and pressure plate - these all need to be the matching standard n/a items. ie, turbo flywheel won't work with nonturbo pressure plate), but get the pressure plate customized to increase the clamping pressure to about 2400pounds.
A decent clutch place should be able to do this by re-springing the pressure plate.

I ran this exact setup with an Outback dualrange n/a gearbox bolted to an EJ20turbo and it didn't slip at all, held the power perfectly fine.

Gannon · Post by **Gannon** » Wed Jun 23, 2010 8:54 pm

So you reckon re-spring the Exedy pressure plate over buying a HD no name clutch from Repco?

How much does it cost to re-spring the pressure plate?

Thanks for the speedy reply

AndrewT · Post by **AndrewT** » Wed Jun 23, 2010 10:09 pm

its about 200 bucks at our local place here but I'd say that price would range up and down heaps depending on how often the place you choose does that kind of thing.
I can't speak for how well off-the-shelf packages work as I've never used one.

RST-20 · Post by **RST-20** » Thu Jun 24, 2010 2:50 am

I run a similar setup in my RS turbo.
EJ20G and 00 liberty RX 5 speed with and exedy pink p/plate and std clutch plate, hyd actuation
All mated up to a EJ22 flywheel.
No slip, nice.
Can look for part# as motor is out of car atm??

ScubyRoo · Post by **ScubyRoo** » Thu Jun 24, 2010 12:04 pm

Why would the actuation method make a difference in terms of choice of pressure plate? I imagine you would get more force with the hydraulic than the cable due to cable stretch vs limited compression of fluid?

How are the components different from within the bell housing, i.e. with the cable actuated its the push fork, thrust bearing, clutch plate, pressure plate, flywheel? How is the hydraulic different? Turbo vs. NA vs. 20/22/25 - different dimensions?

Seems as though RST-20 hasn't had a problem mixing components - was that exeedy p/plate turbo specific or NA? by std clutch plate you mean NA?

T'subaru · Post by **T'subaru** » Thu Jun 24, 2010 12:11 pm

here is what i purchased off ebay for my ej20g conversion, im using a Legacy n/a 5 spd trans so my choices were limited, wish I had the turbo trans.
Cheers, mark
http://cgi.ebay.com/ebaymotors/F1-RACIN ... ccessories

T'subaru · Post by **T'subaru** » Thu Jun 24, 2010 12:15 pm

ScubyRoo wrote:Why would the actuation method make a difference in terms of choice of pressure plate? I imagine you would get more force with the hydraulic than the cable due to cable stretch vs limited compression of fluid?

How are the components different from within the bell housing, i.e. with the cable actuated its the push fork, thrust bearing, clutch plate, pressure plate, flywheel? How is the hydraulic different? Turbo vs. NA vs. 20/22/25 - different dimensions?

Seems as though RST-20 hasn't had a problem mixing components - was that exeedy p/plate turbo specific or NA? by std clutch plate you mean NA?

I think the main difference is a pull vs push clutch set up, cable vs hydraulic, I was ready to order a stage 3 500.00 leg turbo set up until someone smarter than I spoke up and prevented me from buying parts that would not work for my application.
Cheers, mark

AndrewT · Post by **AndrewT** » Thu Jun 24, 2010 1:10 pm

yeah it's push vs pull that makes the difference.
Pull is only in the turbo gearboxes, which have no dual range, so don't apply to this thread at all.
They use pull type clutches in the turbo gearboxes as they are more suitable for high powered applications - less clamping force is required to handle similar power as the clutch is naturally held on more tightly as centrifugal forces increase - that's how it was explained to me once anyway.
But push clutches are perfectly fine for turbo applications if they have suitable clamping force.

Push and Pull clutch setups are completely different. The bellhousing of a pull clutch gearbox has major differences to accommodate the pivot point rod, the fork operates the other way around (pulls the centre of the pressure plate instead of pushing it to release the clutch). The slave cylinder mounts on the gearbox are different to accommodate a different slave cylinder (with different throw length) and it mounts the opposite way around too.

It's a common misconception that cable vs hydraulic has something to do with push/pull. It doesn't.

The turbo pull-type gearboxes are all hydraulically operated.
The non-turbo push-type gearboxes are almost all cable operated, but some are hydraulically operated too.

As a general rule of thumb DO NOT mix components. If you want your clutch setup to work you need to use the matching clutch/pressureplate and flywheel for the gearbox - just up-rate the clamping pressure to suit the power of the engine.

Gannon · Post by **Gannon** » Thu Jun 24, 2010 6:40 pm

Cool. So i'll go grab a NA flywheel and get it surfaced.

So opinions,.... Re-pressured Exedy or cheaper Repco HD?
(assuming both end up costing the same)

AndrewT · Post by **AndrewT** » Thu Jun 24, 2010 7:40 pm

Grab any old stock pressure plate (an NA one to suit your gearbox) for free or 5 bucks and get it re-sprung. Then it's as good as a brand new one and can be sprung to your specifications (about 2400pounds is good). Also good idea to get the surface of that skimmed too. That is my advice

Gannon · Post by **Gannon** » Thu Jun 24, 2010 9:01 pm

AndrewT wrote:Grab any old stock pressure plate and get it re-sprung

Hey good idea, then i only need to buy a new clutch plate

Gannon · Post by **Gannon** » Fri Jun 25, 2010 7:25 pm

Looking through a PBR clutch catalogue today, i noticed that the part number for the EJ22 clutch plate is the same part number for the EA82 clutch plate.

But comparing the specs in the FSM, the EJ22 shaft has a diameter of 25.2mm and 24 splines, the EA82 has the same 25.2mm diameter but has 25 splines

The EA82 only has a pressure plate force of 350kg, where the EJ22 has 450kg and the EJ20 turbo has 620kg

guyph_01 · Post by **guyph_01** » Fri Jun 25, 2010 8:06 pm

i'd buy a new thrust bearing too... You don't want to put a second hand one in only to find out it squiks. Really annoying!!

AlpineRaven · Post by **AlpineRaven** » Fri Jun 25, 2010 8:16 pm

guyph_01 wrote:i'd buy a new thrust bearing too... You don't want to put a second hand one in only to find out it squiks. Really annoying!!

I agree its not worth it because it could last for a month and its a PITA to remove the gearbox again!
Cheers
AP

AndrewT · Post by **AndrewT** » Fri Jun 25, 2010 8:27 pm

Be sure to do spigot bearing too (the one in the centre of the flywheel).

Might be an idea to inspect and maybe replace your rear main oil seal on the motor while it's all apart.

Gannon · Post by **Gannon** » Fri Jun 25, 2010 8:58 pm

Yep, they are all on my to do list

AlpineRaven · Post by **AlpineRaven** » Fri Jun 25, 2010 11:17 pm

AndrewT wrote:Be sure to do spigot bearing too (the one in the centre of the flywheel).

Might be an idea to inspect and maybe replace your rear main oil seal on the motor while it's all apart.

get em from SKF or CBC - i think its 6201 bearing (less than $5-$7), Subaru makes profit on that bearing!!!!
Cheers
AP

Gannon · Post by **Gannon** » Sun Jun 27, 2010 6:02 pm

What'a you know, the EA clutch plate fits on the EJ gearbox.

So now i just need to hit the wreckers for a flywheel and pressure plate.

The EA thrust bearing appears to fit, except that the 2 little wire clips that hold the bearing to the fork are too big to clip over it. This makes me think it wont work with the EJ pressure plate.

So i also need to source a thrust bearing, spigot bearing and both the engine rear seal and the gearbox input seal.

I'll call the clutch place in Coffs Harbour tomorrow about re-springing the pressure plate. Might go for a pressure of around 700-800kg, which should be fine for an RS engine running maybe a little more than stock boost. Id rather the clutch slip than the gears.

RST-20 · Post by **RST-20** » Sun Jul 04, 2010 1:46 am

ScubyRoo wrote:Why would the actuation method make a difference in terms of choice of pressure plate? I imagine you would get more force with the hydraulic than the cable due to cable stretch vs limited compression of fluid?

How are the components different from within the bell housing, i.e. with the cable actuated its the push fork, thrust bearing, clutch plate, pressure plate, flywheel? How is the hydraulic different? Turbo vs. NA vs. 20/22/25 - different dimensions?

Seems as though RST-20 hasn't had a problem mixing components - was that exeedy p/plate turbo specific or NA? by std clutch plate you mean NA?

Sorry I have taken so long to answer this guys, as stated before gearbox is 00 Liberty RX 2.5l N/A, push type accuation, hydralic operated, so not turbo specific.
Gearbox seems similar to wrx internally diffrent clutch accuation,
look here: http://www.rslibertyclub.org/forums/sho ... t=flywheel
I use a std EJ22 flywheel that has been machined (from memory it 8.1 kg)
{This is pretty normal occurance for dual mass flywheel liberty's to replace flywheels with old EJ22 flywheels}
Clutch plate part # FJD25U, no pressure plate number but defineately a Exedy pink which is still like new (clutch plate is worn a little)
hope this helps