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Clutch upgrades for EZ30 swap?


natext6
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I'm finally getting a move on with my swap project. icon_cool.gif 

I've decided to use the FT4WD 5spd transmission from my current xt6 with an adaptor plate and redrilled flywheel (courtesy of SJR).

BUT, are there any upgrades that I should do/ that are even available for the xt6 clutch? I'm worried that the stock xt6 clutch may not be able to handle the extra HP/torque of the ez30.

 

I've been on Ebay, and I've noticed that you can get stage 1-2-3 clutch kits for/that fit the xt6, but I have no idea if they're a quality product, or if they will even help. I'm also still not sure what each "stage" means either.

Any help would be greatly appreciated.

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My ej25 stock clutch had trouble holding EZ power. No way a stock Xt clutch is going to hold it. Tranny probably won't either.

 

Not to go off-topic, but you might just consider going with a tranny that fits an EJ/EZ and use its clutch. 

 

I've considered the concept of simply using another transmission and clutch setup, but hey, I've got this transmission, and I love the diff-lock, So what the eff. why not give it a go! Worst thing that happens is the transmission blows, and then I would even have the option of swapping internals or something.

 

SO. Back to the question at hand :P

 

How could I upgrade my clutch for it to be able to handle the ez30 power?

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OK, I will pyle-on, too, but this will be my last plea for sanity:

 

Subaru put an automatic behind the SVX'x EG33 for a reason, and that reason was that none of their MT trannys in 92 could handle the power.  Get a clutch that will hold, and that tranny won't. 

 

An FT single-ratio tranny is uncommon.  Sad to see one die when it could live happily forever behind my EA82.

 

Good luck with your quest.

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I MIGHT be possible to substitute your diff-lock for the later VLSD.  Some have had experience swapping parts between Legacy and pre-Legacy trannies.

 

Is there a particular reason that you prefer the lock over a VLSD?

 

I just like being able to lock the vehicle into 4wd when I so desire it.

 

I did quite a lot of sideways last year in this vehicle, and I loved the obvious cornering differences between the "Awd" and 4wd.

 

I might also add, that I work at a Subaru dealership, and have driven all the newer vehicles QUITE a lot now, and for some reason, I've found that none of them are balanced as well as the xt6 is. (Although I may just be fooling myself, you never know!) I've found that I've been able to perform in snow, for instance, much better with the xt6, than with the newer (VLSD) vehicles.

 

Does this match up with anyone elses experience? I'm open to all opinions, I started this thread to explore all the options after all!  B)

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Does this match up with anyone elses experience?

Absolutely not.

 

I've only driven one Subaru made in the last few years (well....I guess 2 counting the Scion FR-S...). But I have driven probably 20 90s EJ cars with various mods (or not), on an ice racing track. Most with dedicated snow tires. VLSD performs much better.

 

This includes my '88 XT6, which I drove for awhile stockish (coil springs), then put EJ transmission internals. The only things that changed were slight gear ratio change and VLSD center. MASSIVE improvement!!! Then I did the EJ front knuckles....Again huge.

 

My FWD, 1.6, Auto trans Celica is more fun to drive on the ice than any of my FT4WD Subarus were (on the same Blizzak Revo1s, which were brand-new on my loyale, and are currently on their 6th season on my Celica). And I would bet, faster.

 

 

I bet the "improvement" you are feeling when locking the center diff, is the open diff sucking so bad.

 

 

 

My experience, is while on pavement (center diff unlocked) you are at the mercy of your tires while off throttle, and then when you get on it in a tight bend (where AWD has it's advantage over 2WD) you just get one front tire spinning like mad. Aweful.

 

In low traction racing, be it dirt or snow/ice, you have the same problem when unlocked, you have the same problem. But then when you lock the center, the EA alignment (camber, caster, ackerman) means that the front looses grip first. Only with some serious weight transfer can you get the car to rotate. And only with a rear LSD can you really hold it.

 

The VLSD center offers just enough give to let the front tires grab on turn-in, but when you load it up, that thing grabs pretty hard. I've seen a stock 4k VLSD center diff perform in a lifted Impreza on the rocks, and was massively impressed. I am confident that it is a very strong unit when it needs to be.

 

 

I plan to run a true 4WD 5MT in my '89 XT6 for RallyX, but that's mostly for the FWD setting, as I'm considering running a welded rear. I also have the EJ knuckles for camber and ackerman correction, and will be spacing the leading rods for castor correction. Also, significant weight reduction/relocation to get the balance more were it needs to be.

 

 

 

 

I have said it before, and I'll say it again. I loved my FrankenWagon, but I HATED that transmission (RX FT4WD D/R).

Edited by Numbchux
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If you go with a pull clutch EJ transmission from a turbo car they have much stronger clutch release forks and there are plenty of upgraded aftermarket clutches for them.

 

The pivot ball on the push type transmissions can wear into the fork and punch through, leaving you unable to release the clutch. It happens often enough with stock clutches, go to a higher spring tension aftermarket and its even more likely.

 

The EA boxes are 3.9 or 3.7 differential gearing. EJ has up to 4.44, so that's another advantage.

Plus it bolts right up to the EZ engine.

 

I'll quote Numbchux because it is so accurate:

"I bet the "improvement" you are feeling when locking the center diff, is the open diff sucking so bad."

The locking center diff sends ALL the power to the end of the car with the LEAST traction when it's not locked. Which is usually the front inner wheel when taking a turn and trying to accelerate due to weight transfer from the body of the car rolling on the suspension. The viscous center diff fights that so at least a fair portion of the power goes to the end of the car that still has traction.

 

The full time 4x4 is really a pointless system. It's only good for accelerating in a straight line on a perfectly even surface. It has no advantages over the FWD/4wd transmissions and returns poorer fuel economy because the rear driveline is running under a load all the time instead of coasting. It comes down to an advertizing gimmick.

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we take the 2wd legacy trans case and install the push button loyale guts into it gives us a legacy ej push button five speed have done 3 or four now is hard to find a 2wd ej case but then you do not need addaptor and can run the big clutch. We have put ej2.5 turbos up to thiss trans and no problems yet have not tryed to use a diff lock rear section but may work key is the 2wd ej case

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I think F/R LSD will assist in an open diff situation.

 

Also Chux, do you think it would be possible to run a Cusco 35/65 Tarmac center diff in a ea trans?

 

Front LSD is a band-aid for the real problem. And it would have to be such a strong LSD to overcome the free-spinning front tire issue, that it would likely still cause understeer, by not letting the front tires spin at slightly different speeds. I had considered this too, back when I was running that trans, and WJM and I had a pretty lengthy discussion about how well that would work. The consensus was.....not. Certainly not enough to justify the cost of one (again, it's cheaper to do it right....VLSD center).

 

Also:

 

As is always the rule with Subaru transmissions, front pinion gear has to match the center diff.

 

 

 

 

 

 

 

the rx turbo trans runs primary rwd when diff locked runs 4x4 but unlocked is mostly rwd

And....no. It isn't. It's a completely open center diff when unlocked. Absolutely no restriction or mechanical bias. In fact, the rear LSD means that the front is more likely to loose grip first.
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What are your intended uses?  (As in, how likely are you to handgrenade any particular tranny, and what kind of driveability do you need.)  Street, trail, DD?

 

Time to put on my Nomex suit and take one for my team:  Put in a 4EAT.  (Maybe a 5EAT, but they are outside my experience.)  "What?", I hear you say...  Am I MAD!  Well ,yes, but that isn't relevant here.  Unless you are doing technical trail riding that requires precise power control, a properly set-up 4EAT is likely to have the best chance of surviving the EZ30.  No clutch to ever burn out or break, smooth power, torque multiplication, low shock loads on other drivetrain components.  Do a paddle shifter conversion and it might even be fun.

 

OK, manual trannies:  Probably nothing from a first gen Legacy (90-91s seem to have major issues).  Maybe second-gen and/or WRX.  Let the new-gen people tell you what's good.

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Definitely not going auto.

 

In terms of what I intend to use the vehicle for, I would say somewhere in the realm of "street" in that I want it to be a reliable car that I can use as a DD, but I also want some performance for when I want to have some fun :lol:

 

Also, I'm going to play the idiot card here quickly as I can't remember off the top of my head. XT6, push or pull style clutch, I'm pretty sure push, but memory has failed me.

 

Oh hey, here's a question to strap on to the back of that one as well. Are there any options for modifying push/pull to the other option?

Edited by natext6
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