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Oh damn, that's a very good point. I'll shoot @PressY4Pie a message next week, he's been doing all sorts of wiring and module trickery on his RX8-swapped NC and probably knows a thing or two about that. Obviously the RX8 and NC ECUs themselves are way different, but they might share the same CAN protocol..?
Got the 8HP box yesterday and started d*cking around with it after work. Pulled the valve body and confirmed the internal TCM part number is one that's supported by both MAXX and Turbolamik (0260550076). Didn't expect there to be an issue since all 8HP45's are considered Gen1 gearboxes which MAXX supports.
Messed with more stuff this morning. Used my spare motor for mockup and mounted the Land Rover flexplate and the starter. The Jag starter needs just a hair of extra clearance to fit the Duratec block, but otherwise bolts right up. I started taking a grinder to the boss that it was making contact with, but decided to cut down one of the starter's screw heads instead.
Went to the local driveshaft shop during my lunch break with my spare Miata and Jag driveshafts and asked them about splicing them together. They said don't bother, but they could make me a 2.5" steel shaft (same as what's in the car now) with a slip joint for $765. Spicer U-joints, no adapters. They had the flanges for the 8HP output and Miata pinion both on hand. I'll probably have them make the shaft. Gonna try to bolt the trans in the car and take shaft measurements next weekend or the following.
Then of course I had to bolt the trans up and make sure this wasn't all really too good to be true. She fits! Bellhousing pattern is spot on and the Land Rover flexplate mates to the torque converter no problem.
I'll dive deeper next week and probably start ordering some parts for the swap. I'm pretty well decided on going with the MAXXECU at this point, but don't want to make a hasty decision right before leaving for a race weekend. Next week, I'll for sure order a trans mount adapter, some of the small wiring parts, and whatever aluminum trans pan @Watterson02 was just talking about.
Kinda want to get into it more this afternoon but gotta shift gears and get ready to head up to Buttonwillow tonight. Entry list for my class this weekend looks like things are gonna be tough. I'll likely be fighting for 3rd place at best. Should be good fun!
Not much to add besides another vote of confidence for Maxx. Started off with one on my old UrS4, loved it so much that I installed them in both my Evo and RX7. I've played around with virtual tables and custom math channels, barely scratching the surface from what I can tell. Gives me the impression you can pretty much do anything you want / extend out of the box functionality with enough time. Keep it up man!
Maybe I'm too cheap, but I'd do some shopping around before jumping on that driveshaft pricing. On the other hand I imagine you're a bit cautious after how your last transmission swap driveshaft experience went and if you trust this place, that counts for a lot.
I paid less than $450 out the door for a more complicated custom driveshaft on my Jeep, also from a local shop after I too had issues with parts that were shipped to me. That included a double cardan CV joint and a slip joint. I don't think you need neither of those. Maybe a lot of the cost is in the 8HP output flange? Low volume, custom driveshaft flanges/slip yokes can be expensive, but besides the possibility of the adapter flanges being most of the cost, this is otherwise a 2.5" piece of tube and two standard u joints that they run on a balancing machine. I'd expect it to be closer to half that price.
Edit: I see now that the 8HP runs a hard mounted yoke, not a slip yoke, so I guess that means you need a slip joint in the driveshaft. Still, it seems expensive to me.
Last edited by OptionXIII; Apr 20, 2026 at 12:58 PM.
Switching gears from the trans swap for a minute. NASA SoCal Round 3! The little car boogied this weekend!
Nico F. was back this race (far left 'stang in the pic). He's another one of the S550 Mustang crew and was actually an instructor at the first track event I ever attended. He missed last month's event, but had beat me at Chuckwalla back in February by a full second. I was hoping I could come close to him this weekend. Just .05 seconds separating us on Saturday!
I've got no idea what was going on with my helmet here, I don't remember fidgeting with it this much lol.
Fastest lap from Saturday. Definitely not my best-driven lap of the weekend, but it got hot out after session 2 and times slowed down a lot. We ran two different configurations as opposed to the usual CW13 this weekend, CW1 and CW13A. Both configurations change only one corner, but it still took everyone a bit to get dialed in.
Also finally got to meet @codrus in person after barely missing each other at NASA events for over a year! Naturally, we were both busy as hell and only had a limited time to hang, but it was fun matching a face to the name and chopping it up with someone who knows way more about this stuff than I do.
The car ran great all weekend. Only hiccup was an O2 sensor failure. Otherwise, I just checked oil and tire pressures and torqued the lug nuts every couple sessions. Rotated the tires Saturday night as well. The engine seems to be enjoying the extra crankcase venting I added since last event. I used to get a little bit of oil seepage out of the oil fill cap and dipstick tube, but that's gone now.
It's been super fun getting to know and hang with the TT3 crowd this season. Despite the fact that I'm not driving an American V8, the rest of the group has been very welcoming and the camaraderie has been great. Lots of laughs shared about the lowly Miata running around with all the Mustangs on track.
The meat of TT3 group. From left to right: Tom (Land Yacht, who generally dominates us every race), Nico, Natalee, and Greg (Tom and Natalee's dad). I know American muscle is supposed to be the enemy, but they're great people and have been fun to hang with.
The racing on Saturday morning was great. First session was a bit of a throwaway due to two cars breaking down in the first session. Second session, Nico and I gridded close together and set times within .05 seconds of each other. Third session was much warmer out, and quite a few people didn't even bother going out. I tried to make up time, and drove a lot better, but ultimately ran 0.4 seconds off our pace from session two. The rest of the guys said Nico was in the trailer, eyes glued to Speedhive saying, "He better not go any faster." We had five sessions on Saturday, and I ended up running all of them, but was still fastest in session 2.
Holy f*cking helmet hair, Batman.
Sunday went better, almost a lot better. Tom didn't show up to session one, apparently he caught a bug of some sort Saturday night and was running late. I slid into first place by a decent margin and was hoping I could hold onto it in case Nico came back for vengeance in the next session. Fortunately, I didn't have to worry about that, because Tom made it in time for session two. We had him grid in front of me, despite not having a lap time yet for the day, and I managed to kinda almost hang on to his tail for a couple laps! Would've been the best GoPro footage of the weekend had I not left it on the charger in my van We pulled into the pits and I was only 0.7 off him for the session. Closest I've ever come and maybe the closest I ever will be haha. A firm handshake and some laughs were exchanged after. Good stuff.
Sunday afternoon: always the saddest part of the weekend.
Car's back at home in one piece and we're headed back out to Buttonwillow this coming Sunday for my buddy's track event. I'm gonna bolt the passenger seat back in, pop on my burner 235s, and probably just spend the day giving people ride alongs. Maybe try and weasel my way into driving a couple buddies' cars. Should be a fun time. After that, I've got until mid-June for the car's next NASA event. Depending on timelines, I might be able to slam the 8HP trans in before then. Got some really good things in the works on that front but still need to confirm a couple things before getting too carried away. I appreciate the above input on the 8HP bits and MAXX recommendations! Much more to come on that soon.
Evil thread leads me to Googling 8HP + Ecoboost conversions. I really should get my project running before contemplating dropping even more money on it.
The wrecker down in Chula Vista has another for sale for $250... just sayin.
Alright, in a week and a half I've gone from "I'll just wait on a trans swap 'till I blow up all my six speeds." to "This thing is gonna have eight f*cking gears in it by Summer."
Pulled the trigger on a MAXXECU today, including the flying leads, an 8HP trans connector, and 10-pin BMW shifter connector. Already started messing around in MTune last night, and sent @Wingman703 and @Watterson02 some annoying messages. Even got Wingman's tune for all of you currently in the process of swapping an 07K into your cars. Hit me up, I'll share it for $50.
Real wide range of topics in the email inbox this AM.
In all seriousness, the MTune software keeps things really simple and I'm excited to mess around with a standalone again. MAXX doesn't have basemaps for an NC yet, but they do have the NC cam and crank trigger patterns preloaded which is really nice. There's also some great touches in there like having preloaded data for what might be hundreds of injectors. I was advised by someone on FB to steal some data from Haltech's NC basemap to use in my tune. Haltech also has a great info page regarding NC ECU inputs and outputs. I didn't have dwell time for the NC's coils offhand, so this potentially saved hours. Thanks Haltech, sorry I didn't buy anything from you.
Big developments on the drivetrain side of things. On Sunday, an FB user posted up that he wanted some beta testers for his NC PPF to Jag 8HP45 adapters. I signed up for that immediately. He ordered parts this week and said the next test units should be ready in 4-6 weeks. I paid $360 for mine and he said he can do another couple at that cost, then they'll go up to $550 when/if he brings them to production. I've talked to this guy at length now and funny enough, he also bought his NC out of spite after fighting driveline vibration issues with a KPower ZF5 swap in his turbo NA.
The same dude also figured out a potential off-the-shelf driveshaft option. Insane. I don't know how one figures this stuff out.
I've got time so I'll wait and see if it works for him and anyone else. He said total parts cost was under $300.
By some weird coincidence, one of my buddies just swapped out his 3-series shifter for a fancier looking one. He brought his old one to the track this weekend and gave it to me in exchange for an order of the world famous Buttonwillow Cafe cheese curds.
My original plan was to get the MAXX wired up and connected to the car's CAN, then use it to control the transmission only. I dug through the internet and found a couple instances of people saying the NC and RX8 CAN protocols are almost if not exactly the same (MAXX has the RX8 protocol built in). I think that's almost irrelevant though, since I'll be waiting over a month for that PPF adapter. Assuming the ECU gets here in a reasonable amount of time, I think my best bet is to get the car up and running on the MAXX now, and then do the trans later. I've got a bit of time until the next NASA SoCal event in mid-june, and it's probably better that I have the ECU controlling both the engine and trans anyways. I want those snappy-azz fast shifts like in Wingman's POV video.
I bought a second engine harness to chop and splice into so I can get most of the wiring done while the car's still running on the harness that's in the car. There's no adapter harness readily available so I'll have to wire in the ECU one circuit at a time. Not absolutely thrilled about it, but I think it's the best option in the long run, especially after talking to more guys running the stock ECU and 8HP and saying the setup leaves something to be desired.
I'm just saying, I willed this into existence. Speak of the devil and all that.
Originally Posted by OptionXIII
Maybe I'm too cheap, but I'd do some shopping around before jumping on that driveshaft pricing...I paid less than $450 out the door for a more complicated custom driveshaft on my Jeep...
Hopefully his recipe is repeatable. Those early XJs that came with a CV driveshaft are going to be tough to find in junkyards. And the only reason I needed a custom driveshaft for a my manual swap on my XJ is that I couldn't find one in the yard, and the Rockauto unit I bought on sale way before I needed it was junk and wouldn't balance without so much parts and work that a custom all new shaft wasn't much more.
Holy whiplash... that is amazing progress for a weekend.
I shouldn't be surprised considering what you've already shown in the thread.
Originally Posted by Z_WAAAAAZ
I was advised by someone on FB to steal some data from Haltech's NC basemap to use in my tune.
Man that guy must be a huge jerk.
As for the wiring. I don't know how much you care to have PNP capability with the OE ecu (emissions?). I used an extension Harness to then hack up and make my interface, which was super useful as I could then let the OEM ecu manage things like Alternator/charging control and Evap purge, etc. (as well as it was part of the SCCA rulebook that the OEM ECU has to do SOMETHING LOL)
Unless you have a lot of other circuits you want to play with, as well as lightening the harness, etc, you should be able to make your own jumper harness easily from the Maxx to the OE harness. (or even setup a piggyback setup as to not waste outputs on frilly things like alternator control)
These guys can probably make you an extension harness from which to start. https://autosportwiring.com/Products.htm
For a bit of that buyers remorse.... the Gen2 Race just got a firmware upgrade that enables Lua SCRIPTING. which is just crazy.... Adds almost infinite functionality, especially with the twin Canbus and interfacing with OEM busses.
I'm just saying, I willed this into existence. Speak of the devil and all that.
Hopefully his recipe is repeatable. Those early XJs that came with a CV driveshaft are going to be tough to find in junkyards. And the only reason I needed a custom driveshaft for a my manual swap on my XJ is that I couldn't find one in the yard, and the Rockauto unit I bought on sale way before I needed it was junk and wouldn't balance without so much parts and work that a custom all new shaft wasn't much more.
Haha I wanted to respond to your first comment, but by the time I saw it, this was already in the works. Credit's all yours. Good input re: availability. I'll do a search on car-part.com and see if anyone has them around here. We've got a ton of junkyards between LA and the Inland Empire so I might have luck. I'm not committing to that shaft option just yet, but it's pretty damn cool that something can even be pieced together like that. It sounds like my car might be done before his (assuming I don't absolutely botch the ECU install), so I'd be the real test dummy there. I'm not ruling out the $765 custom option either.
I think much of that cost is just the fact of being in Orange County/California. LA, the Inland Empire, and north OC have lots of industrial shops, but there isn't much in south OC, and the increased cost of operating down here gets passed onto us. Most driveshaft/machine/exhaust/etc shops are only open from 8-5 Mon-Fri, which is more or less my exact work schedule, so I'm limited to what's close. First world problems. Woe is me.
Originally Posted by Ironhydroxide
Man that guy must be a huge jerk.
No... it can't be. Really? God damn, small world
Originally Posted by Ironhydroxide
As for the wiring. I don't know how much you care to have PNP capability with the OE ecu (emissions?). I used an extension Harness to then hack up and make my interface, which was super useful as I could then let the OEM ecu manage things like Alternator/charging control and Evap purge, etc. (as well as it was part of the SCCA rulebook that the OEM ECU has to do SOMETHING LOL)
Unless you have a lot of other circuits you want to play with, as well as lightening the harness, etc, you should be able to make your own jumper harness easily from the Maxx to the OE harness. (or even setup a piggyback setup as to not waste outputs on frilly things like alternator control)
These guys can probably make you an extension harness from which to start. https://autosportwiring.com/Products.htm
For a bit of that buyers remorse.... the Gen2 Race just got a firmware upgrade that enables Lua SCRIPTING. which is just crazy.... Adds almost infinite functionality, especially with the twin Canbus and interfacing with OEM busses.
Ok, thanks for starting the conversation on this. I've been pondering the wiring harness side of things a lot and don't even feel like I know the right questions to ask. Here are my thoughts so far:
-I don't need to retain any emissions bits in the harness. I already have the EGR, EVAP purge and leak detection pump, downstream O2 sensor, power steering input, A/C, and intake manifold runner control wiring chopped out of my current harness (but not depinned at the ECU because I'm an underachiever). The smaller and simpler I can make the harness, the better.
-I'd like to have the MAXX control the alternator, which in my car is not internally-regulated. That being said, it's pretty easy to swap an internal regulator into these alternators, if I prove to be absolutely useless and unable to figure out alternator control. I'm running a Mazda 5 alt where my A/C compressor used to be, but the process is the same as the Miata alt. Thanks again, Haltech. https://support.haltech.com/portal/a...67&inline=true
-I think it'd be easiest to just use the factory harness's power inputs/fusebox integration for power supply. Don't want to make any changes there.
-I don't have much, if anything, going on that's going to require lots of extra inputs/outputs. Hell, I'm not even running EBC on this thing and maybe never will (oh sh*t, that might get me flamed). I probably will wire in oil pressure and temperature at some point, since I already have those sensors going to a gauge on my dash.
My best stab at this before your comment would be to grab the spare engine harness, mount the ECU in the car, probably on the parcel shelf, run all the necessary inputs/outputs from the ECU through the firewall, then lay the engine harness in the engine bay and splice all the ECU wiring into said harness. I'm very appreciative you brought up the patch harnesses, though. That sounds much better than chopping the ECU connectors off the factory harness. Having a point to detach the harness inside the engine bay will be nice for engine removal as well, since I'm gonna have to mount the ECU somewhere inside the car.
Thanks for the input. Again, I've never done anything like this before, so I know I'm coming off as a noob. I'm doing my best to touch on the correct points and ask the right questions haha.
Even got Wingman's tune for all of you currently in the process of swapping an 07K into your cars. Hit me up, I'll share it for $50.
Jokes on you, that tune file is from yesterday AM before it made 500whp on a dyno and I figured out a bunch of drivability things. So it's basically obsolete
Originally Posted by Z_WAAAAAZ
The same dude also figured out a potential off-the-shelf driveshaft option. Insane. I don't know how one figures this stuff out.
I've got time so I'll wait and see if it works for him and anyone else. He said total parts cost was under $300.
I want those snappy-azz fast shifts like in Wingman's POV video.
I continue to be insanely jealous of how many off the shelf parts and OE solutions the NC/2.5 have for 8HP. It's all far to sensible and tested.
No... it can't be. Really? God damn, small world .
username as Ironhydroxide didn't tip you off on that? LOL
The H2O Race can be mounted in the engine bay (if you got that) as well as the Gen2 Race.
but if you went with normal Race... yeah, best to keep it under the dash for some weather protection.
As for harness....
First make a pinout map in excel/sheets, line out what, where, what pin, everything.
Then play with the software and make sure each does what it should (you have analog inputs for analog voltages, etc)
THEN make the harness.
I find making a string harness on the car, then laying it out on a large board and putting screws at the junctions and terminations, then running the wiring to where it needs to go along those screws, the easiest.
If you have enough length in the flying leads, I'd advocate for NO SPLICES. get new OEM connectors from Ballenger or the like, and crimp them direct to the flying leads at length they need to be. You can reuse the power and some of the grounding from the OE harness by depinning and running alongside, or as a separate trunk of the harness.
I've done plenty of Piggyback and full standalone installs, feel free to reachout with questions. You're in for a fun wiring headache. They all are to some point. and the best way is to just get through. Keep organized and keep good notes. you'll get through
Jokes on you, that tune file is from yesterday AM before it made 500whp on a dyno and I figured out a bunch of drivability things. So it's basically obsolete
Price reduced to $25.
Originally Posted by Wingman703
I continue to be insanely jealous of how many off the shelf parts and OE solutions the NC/2.5 have for 8HP. It's all far to sensible and tested.
I wouldn't be attempting this at all if it weren't for that. The cost saved from not needing a bellhousing/flex plate adapter alone is insane. Ease of install is icing on the cake. At least I say that now while I haven't even got my hands dirty yet lol.
Originally Posted by Ironhydroxide
username as Ironhydroxide didn't tip you off on that? LOL
I've done plenty of Piggyback and full standalone installs, feel free to reachout with questions. You're in for a fun wiring headache. They all are to some point. and the best way is to just get through. Keep organized and keep good notes. you'll get through
No, I got your non-screenname as it was on Facebook! Lol.
If there's anything I'm good at, it's putting my head down and forcing my way through lol. I'm sure this'll be no different, but I'll take you up on that offer and send some messages your way if/when I hit a wall. I feel fine about ignition, injectors, and digital inputs. Just not looking forward to the DBW stuff and O2 wiring, as the definitions for some of those circuits seem kinda cryptic at first glance on the wiring diagram. I still got more reading to do, though, so I assume it'll all come together more once I do that.
Doin' my best here. Feel free to enlighten me if there's a better way to go about this wiring project.
So I couldn't get ahold of a patch harness from anywhere I looked. General consensus (as stated in the email above) is that NC ECU male connectors are basically impossible to source without simply cutting up an ECU. My current engine harness is fairly haggard and has lots of connectors haphazardly chopped off but not depinned at the ECU, so I decided to just grab a second harness for this project. My plan was to hack everything out of the new harness, then replace the ECU connector with a few 12-pin Deutsch-style connectors.
I'm going to leave the factory ECU in the car, and leave body harness side of the ECU connector plugged in, splicing into the accelerator pedal position signals, brake pedal signal, vehicle speed, fuel pump control, and a few other circuits to feed necessary data to the MAXX. Apparently even the non-traction control NC's will lose ABS function if the ECU is disconnected from the CAN. The workaround is to swap in an ABS module from a non-DSC RX8, which works as a standalone, and is actually said to provide superior function compared to the NC ABS unit. If I can keep the ECU on the CAN and keep the factory ABS happy, though, I'd rather do that and create less work for myself. I'll probably run RPM signal to the factory ECU as well to keep my tach working, along with any other inputs I find the ECU needs to relay to the ABS. Not much information on this out there.
Got my engine harness last night and started cutting out all of the circuits I didn't need, then brought the harness to work today and kept plugging away at it during breaks. Almost all of the electrical tape adhesive under the convolute had broken down and the whole harness was an oily/sticky mess. Spent quite a bit of time cleaning it.
Ended up pulling more wiring than expected out of it. Eliminated the EGR, both O2 sensors (wideband controller will feed AFR to the ECU), evap purge, MAP, manifold runner controls, power steering and AC inputs. Totaled up to be a nice big pile of spaghetti.
Strip't.
It ain't the cleanest thing ever, but rewrapped everything in convolute and it actually looks almost decent. I'll have to finalize the alternator wiring once I put the harness in the car. After frying an alternator due to proximity to the turbo, I relocated it to the other side of the engine and am going to have to shorten that part of the harness considerably.
I had some 12-pin Deutsch-style connectors laying around, so I wired them into the harness. Ended up being 28 wires total, so three connectors. Not extremely pretty, but I couldn't find any ~30-pin connectors that would arrive in less than a week. Our inline connectors at work are stupid expensive too, even with an employee discount. These will work fine. My plan is to mount the MAXX behind the passenger seat, then run the wiring either through the cabin or out through the trans tunnel to the factory ECU location behind the left headlight (I have a relocation kit that moves it vertical and a little further left from the OEM location). Gonna take the car into work tomorrow for general track-prep and will probably mount the MAXX while I'm there.
The MAXX showed up tonight. Thing's got a really nice finish and everything in the box looks to be of good quality. I'm really glad I ponied up the extra few hundred bucks for the package with the flying leads with marked wires (and an extra O2 sensor). Even though I'm not gonna require 70% of this wiring, I'm really glad to not be clamping and pinning each circuit myself lol.
More to come on the ECU project next week. Heading back out to Buttonwillow tomorrow night for my buddy's organization's track day on Sunday. Original plan was just to give a bunch of ride alongs, but the weather's looking really good and I might be able to snag a PB in the morning if all goes well...
NC ECU pinouts listed below. I'm pretty sure about my decision to leave the factory ECU in place with the body side harness connected. Would simplify control of a lot of things. I'm open to input, though.
Bruh, this thread is insane. This trans swap idea has really snowballed since I last checked in. All that and you are still making events and podiuming. Can't wait to see how this swap turns out and what it does for your lap times. 🍿
I'm also on the "can't keep up on this thread" team. I thought I posted this, but looked three pages back and couldn't find it, so here it is again or maybe for the first time:
As far as I can tell, when you press "P", it goes in park but the park pawl isn't engaged by the shifter, it's another solenoid the MAXX doesn't control. So there's a few mechanical park pawl devices Guru offers you might look into.
Also tuned the car that I put that 8hp45 in, and it didn't slip until closer to 700nm wheel, so they're definitely good for more than their name suggests.
As far as I can tell, when you press "P", it goes in park but the park pawl isn't engaged by the shifter, it's another solenoid the MAXX doesn't control. So there's a few mechanical park pawl devices Guru offers you might look into.
This is only when engine is off and the transmission has no clutch line pressure. The release is for the mechanical park override, i.e, rolling a car around the garage or onto a trailer. When engine is on Maxx has full control.
2
We had five sessions on Saturday, and I ended up running all of them, but was still fastest in session 2.
We pulled into the pits and I was only 0.7 off him for the session. Closest I've ever come and maybe the closest I ever will be haha. A firm handshake and some laughs were exchanged after. Good stuff.
