Stock config is no pilot bearing. Same goes for some of the newer mustangs, etc. I do not know why.

So, do these cars use rigid discs in stock form?

From the OE clutch I bought for measurements and then tossed, I can't recall now but I believe it was sprung. The need to go rigid may be influenced by the OE clutch cover being self-adjusting whereas any aftermarket cover is not, but either way the engineers at SPEC strongly cautioned against a sprung hub in this application.

I haven't been around that many dual mass flywheels, but I seem to remember from my E30/E36 days that most BMWs with dual mass flywheels also use rigid hub clutch disks from the factory. They do have pilot bearings though.

I can't tell in the pic, but does that clutch disc still have a marcel spring? My experience has been that the marcel spring in the disc is what keeps the engagement nice and smooth, and the coil springs in the hub are just for NVH. I have a clutchnet organic disc with rigid hub in the car right now and the only way you can tell that it isn't an OEM disc is a little extra flywheel chatter.

No marcel spring

Hi Pass, Any updates? Just ordered my engine and trans for my LFX conversion for carb certified setup 2001 NB. Following your thread and wondering how your doing with your build. Just North of you in Torrance.

Had to wait until several other projects got to certain points and opened up shop space for this. Car goes on the lift to start this coming week. I can't wait!

Car is in the shop! It's finally happening.

Removed the nose, flat bottom and diffuser as soon as I got the car on the lift and took those home since they won't be needed for a while.

Today I pulled the entire drivetrain. Pour one out for this motor, today was the last time a BP will be in this car:

https://www.miataturbo.net/attachmen...ine=1460254159

And then the engine went home with its new owner, by way of a very questionable strap job...

https://www.miataturbo.net/attachmen...ine=1460254159

Engine, turbo, V-mount setup, and exhaust are all off to a local friend so that turbo setup can live on.

Transmission, clutch/flywheel, differential and ECU will be up for sale soon.

Progress!

I also put the car on the scales for a final weigh-in.

Notes for its configuration when it was weighed so I can scale it post-swap apples to apples:
No wing
No diffuser
No flat bottom
15x9 6ULs
Side windows removed
Hardtop on, nose on, splitter on

https://www.miataturbo.net/attachmen...ine=1460254213

Since the diffuser and wing were off the car in the rear, it's a tiny bit exaggerated, but it goes to show how nose-heavy a miata with a turbo system can be, particularly one that saves weight wherever possible since there's a lot of relatively easy weight to pull from the rear and less in the front.

Will be interesting to see what this looks like after the swap. I'll scale it in the same config to get an accurate comparison.

Moar please. And thank you Rocky for clearing out the barn. ;)

Front subframe is in. It may come out a couple times more before all is done but it's in for now!

https://www.miataturbo.net/attachmen...ine=1460788181

V8R frame rail reinforcements are also in. I had tabs welded to the insides of the frame rails for the flat bottom so I had to cut those off:

https://www.miataturbo.net/attachmen...ine=1460788181

Then it was hammer time to straighten the frame rails so the V8R rails could fit over. Here's the frame rails and transmission crossmember in place. No drilling/bolts yet, I am going to wait until the trans is in the car and I've confirmed the crossmember lines up before committing on the frame rail placement:

https://www.miataturbo.net/attachmen...ine=1460788181

With that in place, I turned to the transmission. I want to monitor transmission and differential temperatures on the track. This trans is a bit more costly than a Miata 5-speed so I'd like to be sure it's operating happily, and it would also be great to finally have definitive data on the effects of the flat bottom on drivetrain temperature.

So, I picked up a couple extra Accutech SMI oil temp gauges to use for this. Love these gauges for my engine water/oil temps so it was a no-brainer.

Neither the diff or trans have locations to put the sensors. After draining the trans I stuck a camera in the fill hole and had a peek around to see where there was room to drill and chose a spot just below the fill hole (red mark):

https://www.miataturbo.net/attachmen...ine=1460788181

The sensors are 1/8"-27 NPT. Drill hole with size "O" drill bit, then tap. Basically the same process as you would drill/tap an oil pan for a turbo drain while it's still on the engine; grease the bit and drill slowly so all the shavings are captured by the grease:

https://www.miataturbo.net/attachmen...ine=1460788181

Fill trans with more oil and drain to pull out any shavings that got inside. Then a dab of thread sealer on the sensor threads before install and voila, transmission temp sensor done:

https://www.miataturbo.net/attachmen...ine=1460788181

Anyway of hooking the gauges into the ECU for datalogging? Or do the gauges have a high point.

ECU is GM, won't be datalogging with that on-track. I'll probably add an aim dash later when the funds aren't being sucked away for more necessary parts for this swap, and at that point I can tie the temp sensors into the dash and log. But for now, easy to monitor the gauges - we're talking about oil temps, which rise and drop slowly so a couple glances in a session tells me all I need to know.

The SMI gauges do have a programmable warning light, which I will use.

:bigtu:

It really is surprising how much weight mazda left in the back, I'm guessing that was so they could say they have a 50:50 weight ratio. I almost feel guilty every time I remove weight from the back of the car since I know it's just another chance for people to tell me how bad I screwed it up with the ls, but fuck em, like I said, almost.

Anyway, I like the lfx swaps, excited to see how yours turns out. Really does seem like an awesome option.

The MV5 transmission does have an OEM temperature sensor plumbed in that the MV7 doesn't and might be dataloggable. And just a heads up - you may need to trim the CV joint boot on the driveshaft. Ours got a little mangled during install and we managed to sling out a fair amount of grease. Thankfully we caught it quickly. And good call on waiting for fitment before drilling rails - just remember to keep it even across the body, don't want to put an angle left to right on the driveshaft.

Interesting that the MV5 has that. I'm sure it can be logged if the ECU can see it.

Thanks for the tips. Your thread has helped me add a few things to the to-do list ahead of time that I would have otherwise had to find out the hard way.

Spent a while frustrated with the diff today, it came from the salvage yard with the driver's side axles still in - I figured OK no problem I don't need that but that's fine... went to pop the axle out today and that sucker is not coming out with anything we have in the shop including big ol' prybars and slide hammers. Going to see if Snap On has the special tool for hammering it out through the opposing hole when they drop by tomorrow.. lesson learned: if the salvage yard gives you something strange, there's probably a reason.

In an effort to do something productive today, I turned my attention to beginning the fuel lines. Dropped the rear subframe and gas tank and pulled the hard lines from under the car. Far from glamorous but at least I did a thing. I got a chance to take a look at the only place on my car I've never seen before:

https://www.miataturbo.net/attachmen...ine=1461044312

<- one of those tools that you forget where you put it since the last time you used it was 3 years ago after you fought a junkyard transmission for 5 hours. Works a mint though.

https://www.miataturbo.net/attachmen...ine=1461071151

:)

We have that one actually, it didn't work :crx: