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Yeah, 100% looks better with different color, but takes 1000% more time, +/- 900%.
Get on amazon and overnight some good quality clear bra. Anything you touch getting in/out, cover it. Usually just door bar, maybe the gusset bar you grab to swing in. Most of the stuff you touch will also have roll bar padding on it, but it still helps.
Speak of roll bar padding, sit in your seat and swing your arms around wildly. Anything your hands can touch means you'll shatter your bones. Pad it, and you'll only break your bones. Food for thought.
Get on amazon and overnight some good quality clear bra. Anything you touch getting in/out, cover it. Usually just door bar, maybe the gusset bar you grab to swing in. Most of the stuff you touch will also have roll bar padding on it, but it still helps.
Speak of roll bar padding, sit in your seat and swing your arms around wildly. Anything your hands can touch means you'll shatter your bones. Pad it, and you'll only break your bones. Food for thought.
Clear chafetape on standby, just giving the paint some time to fully outgas before I seal in the flavor. And the drivers side will be fully padded, just haven't gotten around to ordering the SFI padding.
This current endeavor and complete rebuilding of the car was primarily kicked off by one item. That dang weak Mazda transmission.
It's no secret they really don't like torque numbers much more than 270ft/lbs. As the(before I sold them all off to a rebuilder) graveyard of 5/6spd AZ6 transmissions sitting in my basement can attest to... they really don't like it when you shove closer to 400ft/lbs through them.
I always knew there was not a factory Mazda transmission that would hold up to what I wanted, and even built, wouldn't be able to handle power with any sort of reliably. Even Walter only toutes a ~300tq claim to their fully built transmissions. I wanted something that could handle twice that with ease.
So the question became... what do I put into its place?
There's a plethora of options in this space. Even more when you aren't confined to the BP bellhousing, but have the much more widely available K-series pattern to play with.
In short order, the "easy" options are: T56, CD009, TKX, 4speed dogbox, ZF, Getrag 260, or Quaife. (Padlock put your hand down, I'll reference our conversations later).
Because I couldn't make it to easy on myself, I had my own set of requirements to help complexify things.
1. Had to be a transmission that was still... fun to drive. While it is not a *primary* function, this car is still a street car, seeing irregular trips to work, the mountains, or just random carshows. I didn't want something that shifted like an 18wheeler. The T56, while strong is well known for being a clunky, numb transmission.
T56 out.
2. Had to be an off the shelf, or at least an off the shelf-ish, bolt together off the shelf affair. I was NOT going to go down the rabbit hole of one off'ing custom bellhousings, flywheels, shifter assemblies, ect. Not only does this require a level of precision I don't possess(if trying to DIY a bellhousing adaptor), it also gets very expensive contracting someone else to build these items with expensive machines.
TKX out.
3. Had to be something that was streetable. Reference requirement #1. Something that would only be happy shifting at WOT wouldn't cut it in traffic. Only having 4 speeds, and an 80mph capable first gear would be a nightmare trying to navigate even light traffic in.
It pained me but... Dogbox out. Tangent on these:
I really, really wanted to make one of the various flavors of Gforce/Jericho/NASCAR surplus boxes work. Like, badly. There were several strikes against them though. Firstly, 4 speeds is just not enough for a turbo 4 cylinder built for big tracks AND tight hillclimbs, no matter how well it spools. I could gear it tight(rear end wise) for hillclimbs, but then I'm running out of legs fast when I head to Road Atlanta/Road America/Any track that sees speeds north of 140mph. Yes, regearing the box or having an extra with different ratios *could* be an option, but then that's twice the transmissions to have spare parts for, twice the work to prep for an event, and twice the cost to build/install. Also, the required work to make one of those fit is... drastic. As most of them run an LS style 4 bolt pattern, your sourcing a K to LS adaptor bellhousing, then a customish flywheel, AND a crank to flywheel spacer to get the flywheel placement right. Don't get me started on what you need to do to the transmission tunnel to make the starter fit. Oh aaaaand if your shifter rods are external, you're probably doing this:
(hint, this would absolutely not fit with my current MPI seat setup).
4. I have to actually be able to afford whatever transmission is going in. The amount of people(from the general public) that have asked me if I was putting in a Quafe sequential is... more than a few. Yeah, Quafe is waaaay out of my budget, by several factors. Love the "pull the stick, switch the gear" aspects. Can't even come close to being able to afford one(current price for a QBE69G is north of $15K for JUST the transmission. No flywheel, no clutch parts, nada nope.
So um... Quafe is out.
5. I can already hear people screaming at their screens, "Kpower makes swap kits for K to ZF 5/6spd and Getrag 260! Easy button!" Hahaha. Nope. I have my own thoughts about some of Kpower's stuff I won't vent about here, but frankly, some of their kits are crazy expensive for what you get. Plus, heavy steel adaptor plates requiring thicccc flywheels(that, yah know, just sometimes crack), unresolved vibration issues, leaking slave cylienders... The BMW transmissions aren't the cheap options they used to be anymore either, and the Getrag 260 would probably start to struggle to hold up to 500ft/lbs.
Everything BMW from Kpower... out.
6. That left me with only one manual option... the Nissan CD009. This transmission really had the cards stacked in its favor from the beginning. It's incredibly strong(think 1000whp drag racer launching the crap out of these things strong). No 350z owner will say anything bad about their transmission, and I enjoyed the few I test drove. They are still available brand new from Nissan. The only downsides are the fairly tight gears, and the relative weakness of the 5th and 6th gear syncros in the early versions. The only person I was able to find that said bad things about the CD009 was Bronson, who has broken a handful of shift forks in these. But I think he also broke a T56 at one point, soooo I'm fairly sure he shifts like Mike Tyson punches.
There was one other transmission that really peaked my interest, and made it fairly deep into the running.
In the past few years, the BMW 8HP has started to work its way to the forefront as a strong, cheap, extremely fast shifting automatic transmission. Shift times within fractions of a second of a true DCT. It retains a stall converter mind bogglingly enough, and the internal electronics have been worked out well enough that certain aftermarket ECU's have started offering built in support for them(using an external controller, like HTG, is its own can of worms. I'll suffice it to say that... ah... I wouldn't. There might be a cult involved).
The upsides are golden. WOT upshifts maintain boost pressure, all the gears you could possibly want(8, which is a bigger number then 4 or 6), European "Phbbbttt" sounding shifts, flappy paddles, great torque capacity, lightning fast shifts, and widely available.
The downsides though, are numerous. The transmission itself is.. large. And heavy. And deep. As in, ground clearance is negative. Oh, and the adaptors pretty much have to be ordered from a guy in Sweden who makes them in his(probably nicer than mine) garage. The software and support is getting there, but is not 100% there... yet. Still, I'd been an early adopter before(MK60E5 ABS) and it had worked out mostly...
The kicking point was talking to a hillclimber that had made the jump from an H pattern to a true DCT in his car, and struggled for over a year to get it to properly function. Every event I saw him at, he had some sort of transmission issue or glitch. Limp mode, clutches unlocking, rough/unpredictable shifts, all sorts of fuckery. And to fix any of this, he was having someone else remote in and make adjustments. At the end of the year, when it was 98% perfect, I asked him if he would make the switch, knowing what he knew now about how much of a nightmare it would be to get working properly and consistently. He said absolutely not, would have stuck with the H pattern, and wasn't even sure if the DCT was worth *that* much time over a properly geared and setup H pattern box(granted he had an N/A V8 with a faaaat torque curve, not a turbo 4 cylinder, so not quite as much to gain from the tighter gear spread).
I can't rule out the 8HP for the future. When support is better, when the adapters are more readily available from reputable companies, when(if) I'm tired of having a clutch pedal. But for now... she stays stick.
With all this in mind, I was fairly sure the CD009 was the route I would go. And then it was cemented when a local friend/tuner sent me a link to a newly releasing product. A bellhousing style adaptor for K to CD009.
No heavy transmission adapter plates. No fat adapter flywheels. No relocated starters, spacers, or other adapter fuckery. Just a bellhousing that bolts to a K series engine block on one side, and to a CD009 transmission case on the other. Bingo.
Fisch released these for preorder October-ish of 2023. By December, I had an early Christmas present on my doorstep.
They offered two off the shelf clutch options, a traditional ACT single disk, or a Tilton twin disk. Since the twin disk option was only a few hundred more expensive for an additional 300ft/lbs of torque capacity, hell yeah I got the twin disk.
Next, I sourced myself a transmission. I had considered buying a brand new one, yes I really mean BRAND NEW, as Nissan still offers them direct from the factory. But when a used one came up for sale locally that was only slightly sketchy for less than a quarter the price of a new one($600 used vs $2500 new) I jumped on it.
The Fische adaptor requires you to physically cut(like, with an angle grinder) the OE bellhousing off the CD009 to fit their adaptor. It was far easier to stomach doing this to a used transmission then a brand new one when I wasn't 100% sure that it would even fit in the car. I thought it would *probably* fit, since the V8 guys use these from time to time, but since different mounting points and such, didn't know for sure.
And so, I had(what I at the time thought would be) my entire driveline on hand and ready to drop in(yes there is an Explorer 8.8 in these photos. Plans change, details at a later date).
The CD009 is definitely a big heavy girl, but surprisingly the external dimensions are not to different from the Mazda transmission in the places that matter. Where the AZ6 has fat hips that rapidly narrow to a slender size 0 waist and flat chest, the CD009 retains features that can only be described as "built like a brick wall". Brick. Wall.
Hawt dawm I'm a little sad I have to cover up the beautiful flywheel and clutch setup...
While everything was out(the engine had some... not minor work done, but those are yet more details for another time) I gave the igloo a fresh splash of paint, this time properly Lagua blue color matched instead of just a "kinda closeish" off the shelf blue.
I was more than pleasantly surprised to find out I wouldn't have to beat the snot out of the transmission tunnel to make it fit, and I probably won't even need to cut the shifter hole any larger!
Just a little tease... So much more to come, and yet, so much more to go...
Finally, an update I was waiting for... This is one of my favorite builds here. Please keep the updates coming. Is that the final revision of the drivetrain? is it in the car? give us more... the suspense is killing me LOL
Finally, an update I was waiting for... This is one of my favorite builds here. Please keep the updates coming. Is that the final revision of the drivetrain? is it in the car? give us more... the suspense is killing me LOL
"Final"? Well... For now and the foreseeable future, yes I'll be sticking with the CD009, and yes it's currently mounted in the car, which is still firmly mounted on jackstands.
I'm not going to rule out another driveline swap in the eventual future, but currently nothing else meets my requirements.
For the last 5 months of wrenching on this car, I've been filming with the intention of producing a video series showing the amount of fabrication, work, and time that goes into producing a fast Miata. Today, the first of those episodes drop on Youtube.
This is my first go at producing "longer form" content. And to be frank, I sucked at the start of it. The first few episodes where I didn't really know what I was doing, wasn't comfortable on camera, and didn't know what kind of shots I needed... Suck.
As I went on, I became much more comfortable on camera, and became 10x better on the editing and filming side of things.
In my incredibly biased opinion, Episodes 1 and 2 are incredibly bad, poorly shot, clumsily edited, and cringe inducing. BUT. Things start to seriously improve from EP3 and onwards as I kinda got the hang of what I was doing and actually studied up on how to produce an interesting video.
The release of YT content will not detract from any updates here. Only a few episodes have any direct crossover, and this build thread will stay much more up to date then YT will on its two week release schedule(i.e, caging the car has already happened, but the videos for that wont be out for close to two months yet). And of course, the more "technical" side of things will remain here, where it's easier to convey ideas, data, and reasoning, as well as being a better medium for future reference.
The first episode was an enjoyable watch! I always feel like I've barely got enough time to get to everything that needs doing on my car so I gotta give mad props to the guys doing the big projects, AND recording AND editing them so that other people can follow along.
I will definitely be using the clap method next time I pull my motor.
Youtube gets easier as you do it more. I'm socially awkward and I somehow am up to 1M views (EnigmaEngineering - just subbed you). Once you get a video or 2 that really take off, you'll be hooked and motivated to make them ever better.
Then, you'll put your heart and soul into a magnum opus video. And it will get 5 views
I always feel like I've barely got enough time to get to everything that needs doing on my car so I gotta give mad props to the guys doing the big projects, AND recording AND editing them so that other people can follow along.
Originally Posted by canarys2000
Then, you'll put your heart and soul into a magnum opus video. And it will get 5 views
Definitely an interesting experiment in time management. It helps to have minimal family commitments and a garage that's just downstairs instead of a garage I have to drive to.
I never started YT with the intention to go "big", if it takes off that's great but that's not the goal. More wanted to learn how to shoot and edit video(goddam do I appreciate quality content so much more after realizing all the work that goes into them, and what seperates a boring video from an engaging one), while also giving a glimpse into what it takes to build a car of this capability when you don't have a huge budget or a shop backing you. Grassroots.
I had noticed over the last few events the car had run that the motor was developing a pronounced lean to the passenger side, so much so that the oil pan was starting to rub on the steering rack. With the motor out of the car I realized pretty quickly why this was happening.
Apparently the Kpower mounts don't hold up to heat that well. Even with my downpipe wrapped in heat shielding and a 3-4" airgap between the two, the rubber had completely failed and collapsed. I saw a thread a few weeks later in the Kswap group of someone complaining about the same issue, and it seems this is fairly widespread on turbo cars, or N/A cars without the downpipe being wrapped/protected.
To be fair, it wasn't the Kpower produced part that had failed, but the GM rubber mount they had built their kit with.
As there were no solid/higher temp alternates offered anywhere, I wasn't about to throw another $60 rubber mount in to have the same thing happen later. So I got drastic and did something that I might regret later... built a completely solid replacement.
I kept the rubber mount on the drivers side to at least try and isolate the buzzing motor from the chassis a little. I fully expect this thing to rattle my teeth out though, but that's a problem for future me.
At this point I'm 50/50 on weather the mount cracks first, or it buzzes me to death. Time will tell. If it's absolutely completely unbearable, the Kpower adaptor parts were not modified, so I can still stick a rubber mount in. I'll just have to wrap the downpipe, the mount, and maybe duct some air in there as well to try and keep it alive. Or replace that mount every few months.
Speaking of the downpipe, space for it is tight. I took a page out of the V8 guys book and chopped the corner of the engine bay out. This allows me room to actually install/service items in that area(O2 sensor, Vbands).
An extra bonus both of the cut corner, solid engine mount, and no longer worrying about overheating the miata slave cylinder, I didn't have to do that funky "S" bend with my downpipe that I'm sure was awful for flow. So that crappy, cracked, mild steel downpipe got tossed in the trash, along with the entire exhaust.
I rebuilt the entire exhaust, this time in stainless since I could tig it at home. As this car passed sound at NCM with two completely burned out mufflers, I gambled and didn't add them to this edition. Just pure 3" unrestricted stainless from rotational muffler to tip.
Oh, and I built a transmission mount. Nothing fancy there, just a few welded mounts to the chassis and a crossbar that meets up to the transmission mount provided in the Fisch adaptor kit. I will say I am pretty stoked to not have to fight a PPF under here for space anymore.
No PPF because... no Mazda diff. I bounced back and forth between going Ford or Getrag, and eventually settled on Getrag just for availability of axles, and fitting an 8.8 in the space available is... tricky. Those things are HUGE(explorer diffs).
Initially the easy button for axles was to get the Giurintano/Bronson set. Should be indestructible even at high power levels, and replacement parts are easily available off the shelf. Uhh... except... he's apparently hit supplier issues for the shafts themselves. So I'm in a holding pattern for those. Worst case I can resort to the driveshaft shop axles, same ones that V8R uses for their kit. But I've seen people have issues with those when pushed hard as well, so that's going to be a last resort.
Uhh... speaking of V8R... I was a little short on time and patience to fab up a mounting solution, so I contacted them to see if they would sell me just their diff mount. It's a steel bar with two mounts and some bushings on it, I figured it would probably be $200-$250 or so.
Haha. Nope. They quoted me $500. ****. That. With a rusty spoon. Nope nope nope.
So I built the mount for $30 worth of metal.
I had initially grabbed an open 3.42 from the junkyard. The plan was to find a good LSD diff unit and stick it in, but good diffs for the getrag are rather hard to come across. Quafe has an offering but I've not seen great things out of it, and Drexler has a offering but I can't find anyone running it, and minimal information on it. With a possible OSG solution maybe happening at some point, I decided to just grab an OEM G80 and run that for the time being, although I've heard a lot of complaints about them acting like an open on track as well.
For the time being, the driveline is "complete", just missing axles and a driveshaft.
Oh, and I didn't just pull that ratio out of thin air... I played around with gearing calculators for awhile. Turns out the CD009 has fairly similar gearing to the AZ6, so I was able to use that to make pretty close comparisons to where I wanted to be. It was tricky, as I was balancing the need for loooooong legs at big tracks like Road Atlanta, and the vastly different gearing need I experience at hillclimbs. The 3.42 ratio was the best option I came up with to still give me that top speed(192mph with a 7600RPM redline) but still give me useable gears down low(90mph in 3rd should be sufficient for most hillclimbs, with the drop down to 2nd still keeping me well in the powerband)
Last edited by Wingman703; 06-28-2024 at 09:19 AM.
Initially the easy button for axles was to get the Giurintano/Bronson set. Should be indestructible even at high power levels, and replacement parts are easily available off the shelf. Uhh... except... he's apparently hit supplier issues for the shafts themselves. So I'm in a holding pattern for those. Worst case I can resort to the driveshaft shop axles, same ones that V8R uses for their kit. But I've seen people have issues with those when pushed hard as well, so that's going to be a last resort.
After pulling a (maybe insufficient) quick search, I couldn't find anything on these. Bronson from Brofab also has axle options for Miata Getrag swaps? It's too late for me to change things up, but I'm also putting a Getrag in my car. I'm lazy and hit the idiot button though, and ordered the KPower/V8R kit for mine. 30-day lead time for the Driveshaft Shop axles is what I was told.
Was kinda bummed to find out that 3.73 G80 LSDs are basically impossible to find. That ratio would have been great after I add a bit more power at the end of the year. Ended up getting a 3.91 for now but will get on a 3.42 once I up the power substantially and run out of gear at our fastest track out here. At least the diffs are pretty cheap. Interested to see how the 3.42 works at your power level with such a wide range of courses.
After pulling a (maybe insufficient) quick search, I couldn't find anything on these. Bronson from Brofab also has axle options for Miata Getrag swaps? It's too late for me to change things up, but I'm also putting a Getrag in my car. I'm lazy and hit the idiot button though, and ordered the KPower/V8R kit for mine. 30-day lead time for the Driveshaft Shop axles is what I was told.
Bronson worked with Michael Giurintano to bring a beefier, cheaper, more serviceable axle option to market. Using a 100mm CV and 903(I think? This might have changed) axle shafts, the CV's were adapted to the necessary stubs with welded adaptors. The shafts themselves would be pretty much indestructible, and the CV joints were available off the shelf should one fail. The initial prebuy(which happened far before I was looking at diff options) was $1400 a set, well below what DSS charges.
If you're on the facebooks, searching "axles" in the V8 Miatas group will bring up his post, or you could find and PM him directly for details. Or a PM to Bronson and he would be able to point you in the right direction. The current word from Giurintano was he has everything needed, but the off the shelf shafts have been out of stock for some time now.
A quick copy paste from Giurintano's initial prebuy announcement post:
"Bronson McNemar of BroFab and I have been working on trying to find a way to bring a better CV axle option to the market that lets the end user service and choose the parts they want. The 100mm CV is much larger then the OEM Miata outer CV. It's even bigger than the 400hp CV sold by others.
The kit will come with the inner and outer CV adapter and swayaway axle shafts cut and grooved. Everything will be made from all new parts. All parts will be electron beam welded together for the highest possible strength and quality.
We will include Links to the rest of the needed parts from suggested resellers. This is to help keep costs down and so that the end user can service their CVs on their own.
This is also being done so that if you want to buy the CVs from our recommended supplier FCP Euro. You can get the no questions asked lifetime warranty."
Well hot damn, I completely missed the boat on that one. Thanks for the insight, if I have an issue with my DSS axles, it's good to know there are other options out there. Although I really hope I don't have an issue with my axles haha.
You have any qualms about solid mounting the rear of the diff to the subframe? Just noticed your mounts will be solid whereas the V8R brace has what I'm assuming are poly bushings.
You have any qualms about solid mounting the rear of the diff to the subframe? Just noticed your mounts will be solid whereas the V8R brace has what I'm assuming are poly bushings.
Nope. Engine is already half solid mounted, exhaust is solid mounted. Car's not going to be quiet to start with.
If I get bad driveline noises associated with a solid mounted diff I can change it at a later date.
03-15-2024, 11:34 PM
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