Torquing the assembly required a hex drive on my torque wrench. Keep this in mind if you plan to install one of these.

Some slag was found on the steel adapter ring in several places that needed to be cleaned up to sit flush.

I had the flywheel and the clutch pack dynamically balanced after removing the friction surface. Here are the findings and balance marks for referecne.

• Flywheel imbalance 2 grams
• Clutch pack imbalance 5 grams

The shiny bits hung on the engine with new TTY bolts from MWR.

 

Well, after damaging my throttle cable in the Spyder by accident I have been able to put a few miles on the Uniclutch. Note that the power-train engine, transmission etc.. are from an Elise.

Observations:

1. The twins drag more than the OE and single style units. Maybe I can clean that up a bit with a clutch bleed but I doubt it. When I say drag I mean that even when released there is more load on the transmission input shaft. This can be heard when the reverse gear is engaged. There is much more gear mesh sound. Further first gear takes a little more force to engage. This is nothing that really can't be adjusted to by the driver but you should be aware that the syncros are going to see the extra effort at least in stop and go driving. FWIW, this car has the longer MWR push rod installed and still appears to drag slightly. Again, nothing that I really worry about but for a daily driver I would be slightly annoyed. My thought is that perhaps this will go away as the discs wear slightly.
2. The plates DO make noise when floating (clutch pedal depressed). Uniclutch CLAIMS that it is quiet. It is not silent. But it is quiet enough that it's not really noticeable. Sounds like a nice turbo blow off hiss. You can hear this in the attached video. Note that I have NEW throw out bearing, fresh clutch fork pivot and nothing loose. This is the clutch making the noise. Again, WAY WAY WAY more quiet than other multi plate units I have driven but it IS there. Perhaps this will also quiet a bit as the discs self clearance a bit from use and drag less.
3. Shifting SMOOTH and FAST. Even with the drag the inertial mass rotating on the input shaft is CLEARLY lower than OE. I feel that shift speed is likely much much faster now.
4. RPM's / Rev Match. The clutch rotating mass and center of mass is clearly moved in. Given the weights here I was not expecting too much improvement in throttle response. So, I will say this. I am VERY happy I decided to pull the Fidanza friction surface. My feeling is that the mass is just right. Pulling away from a stop requires a tiny bit more focus than OE but the throttle response is improved noticeably but not by a huge amount.
5. Clutch catch. Feels like an organic OE disc with just a slightly narrower engagement point. To that, the engagement point is almost EXACTLY the same as OE. Honestly, this is great! To the point that this feels like an OE clutch.
6. Engine operation. Noticeably smoother. I am not sure how to describe the NVH. The engine still makes the same sounds at cruse as before but there is slightly less vibration. Additionally, I partially filled the loaded side of the motor mounts with 75D poly. So I expected MORE vibration and ended up with less. Fantastic!

Ignore the tires picking up pebbles but listen carefully. That hiss at gear change is not the turbo. MUCH more throttle is needed to get a reaction from the recirculation valve.

 

Everything but item 1 I have noticed on my twin disc setup for 2JZ/R154. But it hardly drags. It did at one time but it was a bad bleed on the system.

 

I'll bleed it again. I think I actually have a speed bleeder I could put on there to help insure that it is perfect.

 

Oh wow you actually bought one. I got recommended it thanks to googles advertising and was curious. Looked to be around 800 all said and done for the clutch and adapter kit right?

Glad you decided to test with the fidanza, I went to order but because the flywheel wasn't oem I couldn't choose from their drop down menu. I don't exactly need a clutch right now so I dropped it.

What drew you to the conclusion that the Uniclutch doesn't need the fidanza friction surface? Could it's removal be a possible source of the plate noise (maybe there's even more room to move around when depressed vs with the friction surface)? I've never owned a multiplate clutch so I only have a rough idea of how it works from videos and stuff lol

 

The Fidanza unit is OEM dimensions. So, when selecting on the UniClutch website you use OEM. FWIW, I opted to not go with the other suggested hardware from UniClutch. You should be able to pick up a clutch pack and adapter by now from O'reilly's and the EOY discount may still be applicable. That would make it the cheapest twin disc for the C series on the market. I ran into some issues when attempting to purchase at the time so I ordered direct from Australia when working with the US tech rep.

UniClutch does not require the flywheel friction surface since all four friction surfaces are contained within the pack. I discussed the plan of attack with the UC rep first before pulling the friction plate and we agreed that to get to similar or less mass than OEM that was probably the way to go. I doubt the removal of the plate has any impact on noise. the rear friction surface is rigidly bolted to the flywheel through the adapter ring.

I will bleed the clutch slave cylinder again and see if it quiets down.

 

Nice video. So the UniClutch is basically a twin disc with its own flywheel surface? Curious to see how your trans holds up over time while boosted.

 

Most multi disc clutches have all their own friction surfaces. Many also have the FW built into the clutch basket so you don't also need a flywheel.

 

Wait... does this mean you could use a flexplate from an A/T - those weigh almost nothing.

PS> Many of the images are not showing - they show as broken image links.

 

Wait... does this mean you could use a flexplate from an A/T - those weigh almost nothing.

ooooo. Are the starters the same between AT and MT 2zz cars? What about the ring gear teeth and size, will that transfer over? Gotta weld on mounting points and space it accordingly right?
So many questions!

As you are the resident guru, I volunteer you to do the testing lol

 

Good news! I used an old trick with silicone grease and a LONG vertical hose to try one last time to bleed the clutch slave cyl. I also cycled the slave by hand several times. While there is still a noise on clutch release it is much reduced. I can get the transmission into reverse without a grind now even at cold idle. 1st gear is still not perfect at cold idle but very livable for what is essentially a race clutch.

Now on to bedding this thing in for a week then I can FINALLY dyno tune full boost properly!

 

Good news! I used an old trick with silicone grease and a LONG vertical hose to try one last time to bleed the clutch slave cyl.

Can you elaborate on this? I'm going to be filling up a brand new master cylinder and slave cylinder on the black Spyder eventually.

 

The team at UniClutch has been wonderful! After working with UniClutch quite a bit to improve the shifting and performance of the Elige drive-train in the Spyder there are a few items to note.

• The longer MWR slave cylinder push-rod for heavy clutches is not needed. If you have one remove it (put the OE one in) and re-adjust the free play. Remember you should probably bleed the system after doing so.
• When refilling the transaxle oil be sure to pay attention to the total volume consumed. Do not pay attention to the fill until it comes out comments/Toyota instruction. It is possible that fluid will come out of the end casing if filled too fast and will not have had a chance to equalize in the center of the transmission leaving your level low. GO SLOW and MEASURE what goes in! It takes time for the thick oil to flow into the large center volume from the end casing.
• The clutch noise seems to be getting a little quieter during shifts. I don't think that I am getting accustomed to it since the sound is now getting hard to hear over the road noise in the higher gears. Earlier this week it was an ominous sound but now it's quieter than the turbo recirculation valve.
• Be VERY careful to select the correct input shaft collar! The adapter kit comes with (several) two that "fit" but only one has zero slack. Test fit and MARK THE RIGHT ONE. I nearly installed the wrong one and I was not in a rush or distracted.

 

Another update....

Shifting continues to improve as I expected because the disc and plate drag is dropping when disengaged as they wear in. Drive-ability is GREAT and engagement point may have moved slightly. I could just be remembering where I set it wrong. Just something to note that you may wish to adjust free play after the bed in is complete.

I attempted to do a pull in 2nd gear last week @ just over 200 miles at 14 PSI. It held fine at 10 PSI. But at 14 I saw a deviation for calculated wheel speed and actual. So, I decided that 200 miles was probably NOT NEARLY enough miles to bed the clutch in a 2000 lb car. I have been driving gingerly a bit more and now have ~500 miles on the clutch. I turned the boost back up yesterday to 14 PSI and had ZERO deviation on the gear vs wheel speed vs calculated speed logs (meaning zero clutch slip). So, it turns out I was right and this is trending in the right direction!!! I think I will crack 1000 miles before I turn the boost up to ~20 PSI again.

TLDR in a light car you probably need WAY more bed in miles to get the clutch to grip properly. So a bit of restraint and patience will be required especially in a track prepped ultra light weight car.

 

I did quite a lot of stop and go driving the past two days. So, I figured everything should be broken in pretty well. Strangely the engagement point has verifiably moved up so the clutch pedal will need to be adjusted. The engagement is now nice, smooth and predictable. Obviously the high engagement point makes shifting a little bit of a challenge but that is not due to the clutch.

Feeling pretty confident that the clutch is holding well, I enabled flat shift today. My impression? Oh man this is nice! Full boost clutch dump from 1st to 2nd gear with my right foot full down is great! I even managed to get the car to hook up in 2nd gear a few times. It's quick and the clutch is behaving so well I am going to further turn the boost up next week.

I will post one more time after the car has been strapped to the dyno for a tune at full boost. But I would say the lessons learned are:

• Adjust the free play several times as the clutch breaks in
• Be patient and put plenty of miles on the clutch pack before applying more than a couple hundred HP to it
• Be sure not to adjust too much throw into the clutch pedal or you may damage the clutch pack and end up with noise like I have
• Do not use an extended slave cyl push rod

 

Sure,

You can apply silicone dielectric grease like the kind used for spark plug coil packs. Take the bleed fitting out or just glob it around the threads. Fit the drain hose to the nipple and route it UP to your collection device.

The problem with the slave bleeder is that the threads ALWAYS leak air back into the piston if not closed completely while pressure is applied. This shouldn't be a two person job but it is because of the stupid design. Using the grease trick solves this.

 

Did you still have to adjust the free play and engagement point further?

 

I had to adjust the clutch pedal free play three times in the first month as the unit broke in. It seems fairly stable now. We will see if I have to adjust a 4th time after I swap the new gear set into the transmission.

 

Bad news everyone.

It looks like maybe the Fidanza may not compatible with the Uniclutch or mine is out of spec.

The last time I had the transmission out I thought that maybe the aftermarket throw out bearing had failed. Unfortunately that is not the case. It appears that the clutch pack has been rubbing on the thrown out fork. Just barely but enough to cause a hell of a racket and very much misbehave when hot. Keep in mind the Throw out, pivot fork and ball were all replaced the last time the noise was heard so these parts are not suspect.

The WORKING theory currently is that the flywheel (aluminum) and adapter ring (mild steel) have different thermal expansion coefficients. When we were dynamic balancing the flywheel and clutch, It was impossible to get the adapter ring onto the flywheel at freezing temperatures but it was a tight fit at room temperature. So, our theory is the ring expanded when the engine and clutch heated up during use and then warped; pushing the clutch pack toward the pressure plate. This explains why there was such difficulty shifting when hot.

Next steps:

1. Verify the height from the crank mounting face to the pressure plate mating surface of an OEM flywheel
2. Verify the height of the Uniclutch plus the offset of the warped adapter ring

I suspect that BOTH the Fidanza flywheel is out of spec (thickness) AND the adapter ring is warped toward the transmission (as can be seen in the pictures). The finding here may be that you cannot use an aluminum flywheel with the steel adapter ring due to the mounting method of the UC pack.

I have contacted Uniclutch for their assessment of what happened. But no matter what it looks like we have to switch to a heavier steel flywheel. If the Fidanza turns out to be out of spec then we are probably ok with just installing the Chromoly wheel. But if it is correct then we may need to consider machining the flywheel for this clutch to work properly when it gets hot. And FWIW, the issues were MUCH worse when hot. This sucks because the total package weight will go up two pounds but there's no way around it it seems.

Damaged TO fork where clutch pack started rubbing

Damage to the clutch pressure plate from rubbing on the T.O. fork at the pivot point

 

Those are the dimensions of a Competition Clutch, Fidanza and MWR. If it can help you checking if your Fidanza has bent/out of specs.

 

Wholly crap it IS thicker! THANK YOU.!

I just bought a new adaptpter ring and a chromoly wheel from MWR. All new hardware is here to go with the new transmission.

I am going to consider machining the shoulder of the pivot ball by a couple millimeters too.

So,

1. Thinner wheel
2. Non warped adapter ring
3. Offset pivot ball

@Funnyman why do you know this stuff? And yes, I would like to confirm the FIdanza is ok. I have a friend who will probably want it since it won't fit in my setup.

 

@Funnyman why do you know this stuff? And yes, I would like to confirm the FIdanza is ok. I have a friend who will probably want it since it won't fit in my setup.

I like experimenting and trying stuffs making my own experience. Be sure that the Fidanza pressure plate is flat before sending to your friend. Over many miles/used, the pressure plate will curved in the center section, requiring replacing the Fidanza pressure plate and bolts.

 

The adapter ring wrapped because of used and has knowned 2 Stg.1 clutchs in his life. Around 110k miles if I remember right. The second Stg. clutch (me new owner) holded many street drag racing. Meaning why the adapter ring got overheat prints.

 

 

So the steel uniclutch plate bolted to the flywheel warped? Remember the expansion coefficient of steel and aluminum is very different. Perhaps that is part of the reason? Or differential heating? I think a steel FW is the fix here.

 

The engine makes lots of power but nowhere near the rated 650 ft/lbs that this unit is rated for. So yes, I think that thermal differential is the ONLY thing that could have warped that ring in that way. Everything was dynamically balanced, checked and rechecked. I suppose the only other idea I have is that the clutch discs could have been warped or offset from each other but I can't think of a way that would cause axial thrust on the clutch pack.

The new adapter ring arrived today. I am going to put it on an end mill just to make sure it's flat. I also am going to take 2mm off of the pivot ball shoulder JUST to be sure even if this thing warps again, Ill have the clearance I need. The MWR chromoly wheel will be here Tuesday. Unfortunately, I'll be in Texas when it shows up. So, I'll have to wait until later in the week to fit this all up and start re-assembly with the new transmission, flywheel etc...

For those of you wondering why I am putting in this much effort for a clutch, look back at the start of the thread. This is the ONLY unit on the market with triple dampened sprung hub organic discs. It drives like an OEM clutch but handles 300% of OEM torque. So, this protects the transmission (to some degree) from the power this setup makes but also make driving the car a breeze. Its a twin disc with zero drive line chatter (ignoring the noise from this obvious little oopsie).

 

!!!!WARNING!!!!

Ok, first let me say I am pissed and I am trying to keep my cool here. Also, the Uniclutch IS a good product. Or at least the clutch pack is. The interface to the adapter ring could use some more engineering effort.

I'll sum up with a TLDR.... The Uniclutch instructions for the Lotus are MISSING CRITICAL INFORMATION. The Lotus (Toyota C-Series & ZZ engines) require a shim, washer, spacer to offset the adapter ring from the flywheel mounting surface. THIS IS NOT IN THE ONLINE APPLICATION INSTRUCTIONS!

Ok, now the long write up with pictures.

A full measure up was required because the adapter ring was found to be broken and UC felt like the clutch pack was bottoming out against the flywheel. This could have been listed as a critical measurement to check but was never mentioned. We just took their instructions be correct.

Notice the outer edge just before the adapter ring where UC was making contact with the flywheel. It is only here because I was running without the friction surface.

The force of the improper assembly caused the ring to cycle fatigue and crack after a couple thousand miles:

 

Proof that the offset was set up per the Exige instructions from UC

Link to UC instructions snapshot:
Dropbox

www.dropbox.com

 

Note the offset step height of the flywheel:

This means the shim needs to be 0.74mm + 0.6mm (flywheel offset + UC offset) 1.34mm at a MINIMUM!!!!

 

Decided to give myself a little safety margin. Made up six 1.43mm spacers and used the MWWR wheel. The step height with the new ring wasn't nearly as bad as the old one.

Ready to go back together. I upgraded to spherical bushings and replaced the cable clips while I was in there. Also modified the clutch fork retaining clip to pull the fork away from the clutch rather than letting it just flop around as was OEM. Fingers crossed!

 

NOPE!

After all that it's still short by a couple mm.

Shorter MWR flywheel
Custom shims
Modified the retention spring to hold the fork on the ball.

I of course could modify the pivot ball or machine a recess in the aluminum flywheel. But at that point I may as well just buy an organic twin disc clutch from a competitor.

I have already wasted too many hours on this. I think even when I first put this in there was an issue because there was a noise then too. It must have always been making contact.

 

How does this work on the lotus? Is the fork different?

 

Same exact part/s both Uniclutch and Toyota/Lotus.

EDIT: FWIW I have transmissions sitting here from a Celica, MR2 and Exige. The bellhousings, input shaft, clutch fork, TO bearing are all identical.