Nth Moto Gen 4 Clutch

[Steve M]

If anyone has followed along in my drag racing results thread here: https://driveviper.com/forums/threads/19581-My-2008-Coupe-Drag-Racing-Results-Thread

...you'd know that I ended up glazing my stock clutch on my 4th pass on drag radials last year at the drag strip. The car was still able to be driven home (but my god the clutch smell), and I can still drive the car, but I'm still pretty far from my goal of running 10s in average weather in the quarter mile, and I no longer trust the stock clutch to get the job done.

I decided to bite the bullet and order an Nth Moto carbon clutch. Way overkill I'm sure, but I've been through enough clutches on my previous toy to know that if you go cheap on an aftermarket clutch, you usually end up with things you don't like, including chatter/squealing/etc. I'm hoping I don't have to go through that this go-around...time will tell.

I ordered the clutch straight from Nth Moto late last week, and it showed up on my door step this morning. Got a chance to unbox it tonight (very well packaged BTW), and it is just as pretty as I'd hoped:

https://image.ibb.co/fnyvKH/Nth_Moto_Viper_Clutch.png

I'll get some better pics of what you get and what's required to install it when I get around to installing it in a couple weeks (give or take). I'll be sure to update this thread when that time comes.

I'm hoping between this clutch and the addition of 3.55s late last year, a good solid 10 second pass in the quarter mile won't be too hard to come by. Again, time will tell.

[Stealth78]

Following (as usual on your threads).....

[viperBase1]

:fpopcorn:

[Back In Black]

It's a shame those things get buried inside the bellhousing where you can't see them.

[Redx]

Good stuff steve, I'm installing mine in the next week or two as well, looks pretty straight forward. Did he end up shipping you two shims? Havent done any measuring yet of which one was necessary, I was curious if you had input on it as well.

Save yourself some hassle and order a remote bleeder from dan cragin, makes it super easy to bleed.

[Steve M]

Following (as usual on your threads).....


:fpopcorn:

Hope I don't disappoint :)


It's a shame those things get buried inside the bellhousing where you can't see them.

Agreed. Half thought about hanging it on the wall for a while...maybe make a clock out of one? That'd be an expensive clock.


Good stuff steve, I'm installing mine in the next week or two as well, looks pretty straight forward. Did he end up shipping you two shims? Havent done any measuring yet of which one was necessary, I was curious if you had input on it as well.

Save yourself some hassle and order a remote bleeder from dan cragin, makes it super easy to bleed.

I only got one shim with mine - mic'd it tonight, and it is 0.160" on the dot. Looks like you have +/- 0.075" of tolerance to play with per their install instructions, so I guess I'll have to see how everything measures out once I'm in there. What are the measurements on what you were sent? I'm assuming they are different?

And a remote bleeder was definitely on the list...I have one laying around here somewhere that I ordered many years ago, and just never got around to installing since you have to pull the transmission to do it. Guess now is that time.

[Redx]

I’m assuming we had the same instructions on how to measure number sounds familiar, I have two shim thicknesses, im away for another 1.5 weeks but I’ll def get them measured up when I’m home.

[Steve M]

Yeah, I'd definitely be interested in seeing what two thicknesses you were given for your install.

From their instructions:

- Using proper straight edges, measure installed release bearing face to bell housing flange (transmission side) distance. Call this Distance A.

- Using proper straight edges, measure clutch finger height position (with clutch installed/torqued) to bell housing flange (bell housing installed) distance. Call this Distance B.

- Distance A minus Distance B should be 0.625" +/- 0.075".

That's with the provided shim installed. I'll measure the slave before and after the shim when I do my install for everyone's reference. I'm definitely curious to see how everything measures out.

[Redx]

Did you purchase directly from nth moto or ard etc? Aaron mentioned he was unsure what shim to use so he shipped both.

[Steve M]

Purchased direct from Nth Moto.

[Redx]

https://i.imgur.com/1sGmsH3.jpg

Which spacer you have? One steel one aluminum and recessed.

[Redx]

Clutch is in, haven’t messed with the slave yet. Instructions state loctite 242, this is incorrect, use loctite 263(red).

https://i.imgur.com/7YQPqsE.jpg

[Steve M]

https://i.imgur.com/1sGmsH3.jpg

Which spacer you have? One steel one aluminum and recessed.

The steel one (top).

[Ninjazx71]

Very nice... in for reviews on this. I've got the McLeod RXT right now and it seems to be holding up to the power very well. If I've ever got to upgrade again I'd love to hear how these ones are.

[Steve M]

I'm at least making some progress:

https://image.ibb.co/fxRgDJ/Nth_Moto_Viper_Clutch_Installed.jpg

Still at least a few hours away from getting it all buttoned back up, but I at least got far enough to measure the clearances to see if the supplied slave shim would work. Looks like it is just within tolerance...hopefully I got the alignment right, but I won't know that until I try to stuff the transmission back in.

[Steve M]

It's been a while since I've updated this thread. Obviously I got the clutch installed, but never followed up with any pics, how-to's, or driving impressions in this thread. Better late than never, right?

I'll break this up into a few posts...one for pulling the transmission, one for the Nth Moto clutch install, and one with my overall thoughts and driving impressions after living with it on the streets and at my local drag strip for 5 months. Updates with pics coming shortly.

[Fatman2006]

:dancingman:

[Steve M]

Pulling the Transmission - Part 1

The first step is to get your car up in the air. If you are doing this on jack stands like a dumbass (me), you'll need to get it at least 20" off the ground in order to be able to actually get the transmission out from under the car. If you have a lower profile transmission jack than what I used, it won't have to be quite as high, but for the one I have, 20" was enough to give me about 1/16" of clearance between the top of the transmission and the lowest part under the car.

https://i.ibb.co/sRCVhKJ/Pull-1.jpg

Next, remove the 40 bajillion fasteners holding the belly pan in place. There are 4 #2 Phillips head screws in the back, and 20 larger bolts that take a T40 Torx bit to remove.

https://i.ibb.co/H75ZB8T/Pull-2.jpg

Now that you've gotten small pebbles and other various road grit in your eyes from removing the belly pan, we're ready to move on to the next task. You'll need to start disconnecting the wiring harnesses (x3) that go to the transmission as well as the clutch hydraulic line.

Here are a few pictures to help orient you to where the 3 wiring harnesses are that you'll need to unplug, as well as the clutch hydraulic line:

https://i.ibb.co/Lr3mWyq/Pull-3.png

https://i.ibb.co/L8KpyC3/Pull-4.png

https://i.ibb.co/54yjy82/Pull-5.png

Bonus: I didn't even realize Sneaky Pete was stamped on the transmission until I started looking at these pics. Sneaky indeed:

https://i.ibb.co/1m89ZwK/Pull-6.png

Now you get to make a decision. The driveshaft has to come out of the car, but before you do that, you need to decide whether or not you want to drain the transmission fluid. If you don't, you'll want to source a transmission plug that will slide in place of the driveshaft yoke to keep the fluid from spilling out of the tail shaft. Something like this:

https://www.amazon.com/Lisle-23400-Transmission-Transaxle-Plug/dp/B000P0U04G

I decided to drain the fluid. You'll need to remove the fill plug first, and then the drain plug. Why remove the fill plug first you may ask? Go ahead and leave the fill plug in place while you drain it, and you'll understand why pretty quickly.

https://i.ibb.co/s2nmHP4/Pull-7.png

As a reminder, if you can't figure out which one is the fill plug, it is literally stamped on the driver's side of the transmission, so you couldn't have possibly screwed this up any more:

https://i.ibb.co/GdbMqXM/Pull-8.png

The drain plug is on the passenger's side toward the rear, close to the transmission mount cross member:

https://i.ibb.co/6FVWv9h/Pull-9.png

Both take a 3/8" drive ratchet to remove.

Now back to that clutch hydraulic line. Here is a good picture of that one:

https://i.ibb.co/ynDY9r4/Pull-10.png

There are various ways to disconnect that line, but I chose to use a tool made specifically for this purpose that looks like this (key fob for scale):

https://i.ibb.co/rswsDSF/Pull-11.jpg

You can get one here: https://www.summitracing.com/parts/mcl-139080/overview/

Yes, I'm aware it is a total rip-off at $10, but it works quite well. You have to be able to push that plastic clip in toward the center of the car to get it to release, and you want to do that evenly to get it to disengage the little teeth that hold the line in place. There is not a lot of room to have your hand in there with any type of tool, which is why the one I show is nice to have.

Now you can remove the driveshaft. Here's what I used to remove it:

- 8mm socket, 1/4" drive, shallow, 6 point
- 4" long, 1/4" drive wobbler extension
- Pry bar to hold the driveshaft in place while you loosen the bolts
- 1/4" drive ratchet, preferably one with a long handle

Here are 2 of the 4 bolts you'll be removing:

https://i.ibb.co/CPPDDNL/Pull-12.png

And here are the tools I used:

https://i.ibb.co/0Xk9bfG/Pull-13.jpg

The bolts have loctite on them, and they are a pain to remove. You'll need to be able to rotate the driveshaft to be able to get the socket on the head of the bolt, hence the pry bar to keep the driveshaft from spinning while you loosen it. You won't be reusing the bolts or the straps, so just toss them once they are out.

[Steve M]

Pulling the Transmission - Part 2

Here's where things got interesting for me. I've used my trusty Harbor Freight transmission jack on my previous toy ('02 Camaro SS), and it worked quite well. The Viper transmission tunnel, however is substantially narrower, and my transmission jack was too wide to fit due to the ears that hold the strap to secure the transmission in place. The frame rails are about 15.25" apart toward the front of the transmission, and narrow down to about 11" toward the rear. My transmission jack was 13" wide, so I needed to lop off the ears a bit and drill new holes for the bolts.

Here it is before:

https://i.ibb.co/C5mwtwZ/Pull-14.jpg

And after:

https://i.ibb.co/KX54Sqd/Pull-15.jpg

Now it is 9.75" wide, and still fully functional. That set me back about an hour. *sigh*

Before you slide the transmission jack in place, do yourself a favor and remove the bottom 3 transmission to bell housing bolts. If you don't, the transmission jack might end up blocking them. They are marked #1-3 in this picture, and take a 15mm, 6-point socket to remove:

https://i.ibb.co/p1bQjm3/Pull-19.png

You can also go ahead and remove the clutch inspection cover. There are two bolts that take a 10mm, 6-point socket to remove:

https://i.ibb.co/5GhhmSX/Pull-15c.png

With the transmission jack in place supporting the transmission, you can unbolt the transmission from its cross member, and remove the cross member itself. You'll need a 15mm, 6-point socket to remove/loosen those bolts.

https://i.ibb.co/W3KKTNw/Pull-16.png

https://i.ibb.co/wzyyBLt/Pull-17.png

https://i.ibb.co/02m049X/Pull-18.png

You'll remove the nut in the first picture that holds the transmission mount to the cross member. Loosening the two other nuts will allow the cross member to telescope inward, and removing the 4 bolts going into the frame rails will let you pull it out. Easy squeezy.

Let the transmission droop a bit - it will make it easier to remove the shifter isolator from the shifter itself. In order to remove that, you'll need to go into the cabin and remove the shifter handle. Pull the trim ring (held in place by 6 Allen head screws - each takes a 3/16" Allen head wrench), and remove the shifter handle (use a 3/4" open end wrench to loosen the jam nut). Set that aside, and take note of the rubber boot. There will be a zip tie holding the rubber boot to the shifter isolator you are trying to remove. Clip that zip tie, and pull up on the boot to dislodge it from the shifter isolator. Now go back under the car, grab a 3/4" crows foot wrench, a couple of extensions, and a ratchet to remove the shifter isolator:

https://i.ibb.co/3NVV5dq/Pull-15b.jpg

If you can't remove this, you'll need to remove the shifter from the transmission. F that garbage.

Now you can remove the remaining 5 bolts (15mm, 6-point socket) that hold the transmission to the bell housing (labeled #4-8 in this picture):

https://i.ibb.co/p1bQjm3/Pull-19.png

All I can suggest is to have a lot of extensions on hand to be able to reach all of the bolts. Once those bolts are removed, you can gently tug on the transmission to dislodge it from the bell housing. There are two dowels that will still be holding it in place, so it might take some force to get them to release. Once you get it to release, you'll start the delicate dance of lowering the transmission while moving it toward the rear of the car. It just barely clears the frame rails, but it does come out.

Now on to the bell housing. There are 10 total bolts that hold it in place - the bottom 4 (labeled #1-4) are different than the top 6 (labeled #5-10). The smaller bolts (#1-4) take a 13mm, 6-point socket to remove. The larger bolts (#5-10) take a 15mm, 6-point socket (I used shallow sockets for both).

https://i.ibb.co/QDxGH4d/Pull-20.png

There are also two wiring harness holders that you'll need to deal with.

https://i.ibb.co/sQDWQ1Y/Pull-21.png

They are held in place by your standard Christmas tree type of plug, but I couldn't for the life of me get them to release. I just couldn't get enough of an angle on them to pry them out, and I couldn't figure out how they unclipped, so I just cut them both:

https://i.ibb.co/h7sDxBf/Pull-22.png

I replaced them with simple zip ties instead.

Just like the transmission, the bell housing is a tight fit. You'll need to dislodge it from the two dowels holding it in place, and then you'll need to rotate it 90° clockwise and pull it down to get it out.

https://i.ibb.co/gRvZb5k/Pull-23.png

Now you can remove the stock clutch. I didn't take any pics, but it's pretty straightforward. The pressure plate fasteners are the only major issue. There are 6, and they take an E-12 socket to remove them. Luckily, I had one on hand. It is not a common socket, though, so plan ahead if you don't have one. Once the pressure plate is out, you can remove the flywheel. There are 8 bolts that take a 17mm, 6-point socket to remove. An impact wrench comes in really handy for this one.

Here's a tip: organize the fasteners you remove by putting them in individual baggies that correspond to the sub-assemblies from which you removed them. Kinda like this:

https://i.ibb.co/wcJmtnt/Pull-24.png

If the project drags out for many days/weeks like mine did, you'll thank yourself later when you are trying to figure out what bolts went where.

[Steve M]

Nth Moto Clutch Install

Some of these instructions will be verbatim from the information provided by Nth Moto, so if you ever lose yours or happen to buy one of these clutches used, you'll have the info. And, of course, lots of pictures to go along with them.

Nth Moto Gen IV (2008-2010) Triple Disc Carbon Clutch Install Guide

***READ ALL INSTALLATION NOTES (ALL 3 PAGES) AS WELL AS THE RPS INSTRUCTION SHEET [details the input shaft lapping procedure] BEFORE ATTEMPTING INSTALLATION***

1. Carefully disassemble Nth Moto clutch on bench and take special note of parts sequence - it is critical for reassembly. The parts are numbered internally; make sure you note the position and direction of them. Proper installation sequence, position, orientation, and direction is vital for clutch to work properly.

There are 9 socket head (a.k.a. Allen head) bolts that hold the clutch assembly together. Grab a 6mm hex/Allen wrench and remove them. Make sure you take lots of pictures before you start flinging parts everywhere.

Here's what you start with:

https://i.ibb.co/TM213gc/Clutch-Install-1.jpg

Note the alignment marks:

https://i.ibb.co/bb8YV5T/Clutch-Install-2.jpg

https://i.ibb.co/mBwZyJ7/Clutch-Install-3.jpg

After removing the 9 bolts and pressure plate - note the numbers (stickers) on each part:

https://i.ibb.co/VpbSqqN/Clutch-Install-4.jpg

And everything pulled apart:

https://i.ibb.co/Tv0zLYx/Clutch-Install-5.png

2. Lap central hub system to the transmission input shaft per RPS directions. The lapping compound and brushes are provided. Be sure to clean ALL lapping compound off before moving to the next step.

RPS Lapping Compound Instructions:
- Clean and remove all dirt and rust from the input shaft and then apply a small layer of lapping compound.
- Slide each disc (note: for this design, it is only the center hub [part #4]) one at a time, back and forth on the input shaft. This action removes any burrs or imperfections from both the clutch hub and input shaft.
- Make sure to completely clean and remove ALL lapping compound from each disc hub and the input shaft with a wire brush.

This is a critical step, so take your time. The hub will be very difficult to move back and forth on the input shaft with the lapping compound on it at first, but it does get easier. I contacted Nth Moto directly about the procedure, more specifically how to know it was good enough. Here is what they said:


We tend to use the compound and put pressure on the input shaft in 90° positions, such as 12, 3, 6, 9 if you will, and drag the hub back and forth until that feels smooth with that angled pressure. Doing that for a short while in each direction will usually get things started pretty well, then finish up with the even pressure movements like you're describing.

If you can put very little pressure on the hub (equally so it pulls straight) and run it all the way to the base of the splines and then back up without effort or worry then you've likely done it well enough.

I spent a good couple hours or so doing this procedure. At one point, I grabbed a jeweler's loupe and went over every single spline on the input shaft, removing any raised edges I could see under magnification (there were a few). Here's what it looked like before I started:

https://i.ibb.co/tMRZcYG/Clutch-Install-6.jpg

And after (2 different angles):

https://i.ibb.co/NNzgFMv/Clutch-Install-7a.jpg

https://i.ibb.co/XYGVj9S/Clutch-Install-7b.jpg

3. Grease central hub system and transmission input shaft with the magic "purple grease" provided. Make sure it covers the input shaft splines entirely, then take a clean towel and swipe the input shaft clean leaving grease only in the splines.

It should look something like this (note the faint purple in the splines):

https://i.ibb.co/rtLtrKS/Clutch-Install-8.jpg

4. Install flywheel with (8) provided ARP flywheel bolts (note: they are 12-point heads, and take either a 16mm or 5/8" 12-point socket). DO NOT use washers. Use Red Loctite on bolt threads. Use finger to lightly lubricate under the heads of the bolts (not threads) with 30 weight motor oil. DO NOT use excess amount of oil and DO NOT allow oil to contact flywheel surface or clutch carbon surfaces during handling. Torque to 70 ft-lbs in an alternating cross pattern.

Here's what you'll start with:

https://i.ibb.co/S091VB9/Clutch-Install-9.jpg

It helps to have a flywheel holding tool like the one shown as you are tightening down the bolts. The alternating cross pattern they want you to use is shown below:

https://i.ibb.co/mJMZ1jv/Clutch-Install-10.png

5. Install clutch internal parts by stacking into the flywheel until flush with standoffs, then stack into the cover assembly. Lift and place cover assembly making sure that all paint alignment marks are in order.

6. Ensure alignment of center hub with pilot bearing perfectly. The length of the hub engagement will make transmission installation difficult if alignment is off at all.

This is another critical part of the install, so take your time. Having the right tool is a big part of this, and was discussed here in another one of my threads (https://driveviper.com/forums/threads/21816-Looking-for-Miller-10018-Clutch-Alignment-Tool). I already had a really nice T-56 clutch alignment tool that had the correct spline count, but quickly found out that the pilot bearing diameters were vastly different (0.59" diameter vs. 0.75" diameter), so I couldn't use it for the Viper.

T-56 alignment tool on the bottom, and the correct Miller #10018 clutch alignment tool on top:

https://i.ibb.co/VV4M9bt/Clutch-Install-11.jpg

When you put the alignment tool in the pilot bearing, there will be some slop. This is normal, but unfortunate:

https://i.ibb.co/b6ZTRts/Clutch-Install-12.jpg

After you slide the rest of the clutch components on to the alignment tool, you need to measure the distance from the fingers on the pressure plate diaphragm to the input shaft, and get the gaps as even as possible before you start tightening the pressure plate cover. Once you start tightening it, you won't be able to recenter it if it gets thrown off. This probably took me a solid hour to get it just right. If you have a lift, lower it down so that the center of the clutch is about eye level. If you are doing it on your back like me, good luck.

7. Use Red Loctite on the clutch cover bolt threads. Tighten clutch cover bolts in a crossing star pattern with small, equal increments (1/4 turn at a time) until the diaphragm fingers all lay equal and the cover is seated to the flywheel. Final torque the clutch cover bolts to 28 ft-lbs.

What it will look like:

https://i.ibb.co/RNNt0j0/Clutch-Install-13.jpg

And the tightening pattern they want you to use:

https://i.ibb.co/Mfq25rx/Clutch-Install-14.png

8. Install hydraulic release bearing spacer under the factory slave cylinder/bearing assembly with (2) provided stainless steel bolts. Torque to 15 ft-lbs with Red Loctite.

I was provided with a 0.160" shim to put under the slave cylinder. The bolts supplied by Nth Moto, however, were a bit shorter than I wanted at 20mm under-head length (the factory bolts were 25mm under-head length). The last thing you want to do is strip out those bolt holes, so I ordered and installed 2 stainless steel M8 x 1.25 x 30mm bolts instead.

https://i.ibb.co/NKdcYRW/Clutch-Install-15.jpg

[pokeyl]

Nice looking, center hub have any springs? Have you ever had a hub without springs before? I just ask because I did a triple disk in a 370z once, and had to take it back out. It was like an ON/OFF switch. I did drive on the street with it but it was not fun. Killed the car each time I drove it. Ended up with a stage +3.
This is the one i took out.
36642

[Steve M]

Nice looking, center hub have any springs? Have you ever had a hub without springs before? I just ask because I did a triple disk in a 370z once, and had to take it back out. It was like an ON/OFF switch. I did drive on the street with it but it was not fun. Killed the car each time I drove it. Ended up with a stage +3.
This is the one i took out.
36642

No springs, and no straps. I don't know how they did it, but it drives smoother than the stock clutch.

[Steve M]

Nth Moto Clutch Install - Measuring for Proper Shim Height

This is another fairly critical portion of the install process. You need a decent straight edge in order to get accurate measurements. Space is tight working in the transmission tunnel, so you need a fairly small one. I went with this 18" aluminum straight edge: https://www.amazon.com/gp/product/B01DQCBHJ6/ref=oh_aui_search_asin_title?ie=UTF8&psc=1

Here are the instructions:

1. Using a proper straight edges, measure installed release bearing face to bellhousing flange (transmission side) distance. Call this Distance A.

In this picture, the bellhousing flange on the transmission is highlighted in blue:

https://i.ibb.co/qDZw7kQ/Measuring-3.png

2. Using proper straight edges, measure clutch finger height position (with clutch installed and torqued) to bellhousing flange (bellhousing installed) distance. Call this Distance B.

In this picture, the bellhousing flange on the engine side is highlighted in green, with the clutch fingers highlighted in red:

https://i.ibb.co/Sf2t0qG/Measuring-2.png

3. Distance A minus Distance B should be 0.625" +/- 0.075". If not, contact Nth Moto at 952-892-0095.

Depending on how I measured mine with the supplied 0.160" shim, I ended up with an A minus B distance of 0.57"-0.58". The acceptable range is 0.55" to 0.70", so I was just within tolerance.

4. If measurement is correct, install transmission per factory manual. After transmission installation is complete, bleed hydraulics by repeated clutch pedal presses from top to bottom of throw like stock.

Clutch Break-in

1. Clutch will be ready for WOT/high RPM shifting after 150 miles of normal driving use with frequent gear changes. Torque holding capacity will rise with usage as well.

[Steve M]

Putting Everything Back Together

I'm not going to go into a ton of detail here, but everything goes back in the same way it came out. I'll highlight a few tips/tricks that have served me well over the years.

First, when reinstalling the bellhousing, you'll see two steel dowels in the engine block. If you didn't know, dowels are used to precisely locate things where the tolerances really matter (like a bellhousing). Bolts never perform this function...they are simply used to clamp things together, not locate them. The two dowels in question are highlighted in red here:

https://i.ibb.co/qMDGsR6/Reassembly-2.png

The dowels will likely have some rust on them (they almost always do), so clean them up with some sandpaper or whatever you might have on hand, and then apply some anti-seize to both. That should help you when/if you ever need to get back in there. Same goes for the two dowels that locate the transmission to the bellhousing:

https://i.ibb.co/5v66tBb/Reassembly-1.png

The only fasteners that get anything applied to them are the flywheel-to-crank bolts, the pressure plate bolts, and the two bolts that hold the slave cylinder in place. All of them get red Loctite. The last thing you want is for any of those bolts to start backing out. Everything else gets reinstalled dry. If you try to use Loctite anywhere else, you'll just be making your life miserable when you (or the next owner) try to take it back apart down the road.

To make bleeding the clutch easier, I installed a remote bleeder:

https://image.ibb.co/ck5bk8/Remote-Bleeder.jpg

How that went together was discussed in detail here: https://driveviper.com/forums/threads/23197-How-to-Make-Your-Own-Clutch-Bleeder-Line

If you are going to the trouble of pulling the transmission, you might as well do that mod. It is a lifesaver when it comes to bleeding the clutch, and will pay for itself many times over down the road.

I'd highly doubt you'd need the transmission filling procedures, but if you do, they are in this post here: https://driveviper.com/forums/threads/23179-Gen-4-Fluid-Change?p=369117&viewfull=1#post369117

Never reuse the bolts/straps that hold the driveshaft u-joint to the differential yoke. Replacement straps and bolts are easily and cheaply sourced...just search for this part number:

https://image.ibb.co/nFn0Co/U-Joint-Strap-Kit.jpg

Here are some of the torque values you'll need for the various fasteners:

U-joint Strap Bolts: 28 ft-lbs
Flywheel Inspection Cover Bolts: 80 in-lbs
Slave Cylinder to Transmission: 9 ft-lbs
Small Bellhousing to Engine Bolts (Bottom 4): 18 ft-lbs
Large Bellhousing to Engine Bolts: 40 ft-lbs
Transmission Cross Member to Frame: 45 ft-lbs
Transmission Mount to Cross Member: 30 ft-lbs
Transmission to Bellhousing: 40 ft-lbs

One trick I used when trying to fish the transmission to bellhousing bolts back in place was to use a little bit of electrical tape to hold the flange head to the 15mm socket. That will keep the bolt from falling out as you are trying to fish the bolt into place, but will easily let go once you get the bolt started in the hole.

In summary, the details matter with this particular clutch install. Good ol' Billy Bob that's been installing clutches for years could probably slap one of these in in a few hours, but it may or may not work as intended. The instructions provided are explicit, so if you aren't doing the work yourself, make sure whoever is follows them to the letter. Make sure they do a good job of deburring the input shaft, and make sure they pay very close attention when using the alignment tool. The extra time I spent making sure it was 100% spot-on paid off when sliding the transmission back in place. I didn't have to use much effort at all to get everything to seat properly. If it isn't going in without banging on it, don't force it. If you force the issue, you could end up cracking something, and that would not make for a good day.

Nth Moto was very responsive to all of my questions. If you get in a pickle, just call or email them. They do support their products, and is why I bought directly from them.

[Steve M]

Driving Impressions

I've said it before, and I'll say it again: this clutch is SMOOTH. My stock clutch would chatter from time to time, but this one does not do that for whatever reason. It doesn't even chatter in reverse, which I've experienced with other clutches in my previous project car.

The biggest thing you'll notice is how much better the throttle response is. The stock clutch weighed in at 61 lbs. on my bathroom scales. The Nth Moto triple weighed in at 38.5 lbs on that same scale. It is interesting to note that the stock flywheel was 24 lbs, whereas the Nth Moto billet steel flywheel was 22 lbs, so most of the weight savings are in the pressure plate/friction disc assembly. This keeps the clutch very streetable...the flywheel still has some inertia to it to help get you off the line, but once you get going, the engine just doesn't have to work nearly as hard since it is no longer swinging around the stock boat anchor. The weight savings also help out your synchros...shifting is noticeably smoother since there is less mass spinning around on the input shaft.

Pedal feel is a bit heavier than stock (but not much), and the engagement is lower in the pedal travel (about mid-travel vs. near the top with the stock clutch). The engagement is also a bit quicker, but very easy to modulate. I can get the car rolling by just letting out slowly on the clutch pedal without using the gas pedal at all. That's the sign of a good, streetable clutch. Now that I've been driving it for a while, I don't even notice that it is an aftermarket clutch.

There is only one downside that I've found thus far: there is additional noise that comes from the transmission when in gear going down the road. If you have a loud exhaust (I don't), you probably wouldn't even notice it. With the windows down, you can't really hear it. With the windows up, having the stereo on at a moderate volume is all that is needed to drown it out. If you like driving with the windows up and the stereo off, you will most definitely notice the noise, and it sounds similar to marbles rolling around in a box. It's just the nature of the beast. I've tried a heavier weight transmission fluid which helped a bit, but the noise is still there. It gets much worse when the transmission fluid gets hot, but goes back to "normal" once everything cools back down. The noise goes away completely under decel. I'm probably one of the few people that use this clutch on a nearly stock car, so if you have headers, you might not notice. I'm not the only one that's reported this noise, so I know it isn't just me. There are no other rattles associated with this clutch, which is pretty amazing since it isn't strapped, and doesn't use a sprung hub. The lack of damping is probably what generates the noise though.

I still have yet to figure out how to launch this clutch effectively...the best 60' I've cut at the drag strip to date is a 1.8, which is pretty sad. There is a fine line between bogging and spinning off the line...there have been many times when I've had both. I will be installing a line lock over the winter to help get some more heat into my tires, so hopefully that will help get me into the 10s like I know the car is capable of. The clutch can be slipped, but the hotter it gets, the harder it grabs. Maybe I just need a more delicate touch, but that's easier said than done.

Overall, I'd definitely recommend this clutch if you have the need. My stock clutch lasted all of 3 passes at the drag strip on drag radials before it started to slip. I don't anticipate that problem with this clutch based on what I've seen so far. If that changes, I'll be sure to update this thread.

I hope this helps someone out there. If you have any questions, fire away...I'd be happy to help in any way I can.

[Vipes]

Awesome write up Steve!! Mods can we make this thread a sticky? I'm looking forward to running this clutch also. Hopefully I can manage to slip it but it sounds more of a challenge from what you're explaining. I decided to run the shorter 26.2 inch Hoosier drag radial to help make the launch a little easier.

[Steve M]

Awesome write up Steve!! Mods can we make this thread a sticky? I'm looking forward to running this clutch also. Hopefully I can manage to slip it but it sounds more of a challenge from what you're explaining. I decided to run the shorter 26.2 inch Hoosier drag radial to help make the launch a little easier.

That will be my next drag radial for sure.