Why not use a 4 port JDM ecu? If I recall correctly a forum member did that when his 4 port engine crapped out, he bought a complete JDM drivetrain and did an auto to manual swap. Seems to me that the JDM would be closer to your final goal than a US 6 port.

I had considered that, but wrt the Copp AP I don't have that particular software. If I have to purchase M/E t]software I could consider it. However, there were some software upgrades I know of for JDM ECUs that are known to cause CEL issues; one was for a ignition coil CEL code that was unique for Japan, and then there might be complications with upgrading it then maybe. M/E might still be able to handle that, but I don't really want to spend the money for add'l pcm software control if I don't have to.

had a break of warm-ish weather where i wasn't busy, so, i successfully completed this modification today.

went to my sacrificial AT 4 port engine harness and de-pin'd one wire [GREEN/BLACK] from the X-18 bulkhead harness plug and one wire [VIOLET] from one the PCM to engine plugs. [picked those colours because pin 4F, per the FSM, is violet, and picked green/black because it was the next wire up on the MT-wired bulkhead] after getting those wires, i crimped and soldered on a 1 pin molex connector. i felt the connector was "needed" because the engine side of the plugs in the PCM compartment include the X-18 bulkhead, along with plugs 1, 2, and 3. plugs 4, 5, and the male pinned section of the X-18 bulkhead are part of the car harnessing. if i ever had to remove the engine loom [say, to pull the engine again], i'd rather unplug the 1 pin molex and have the harnesses separated, vs. having to do more intrusive actions. also, i didn't feel like digging out the car side of X-18, snipping another wire, and extending it to PCM pin 4F.

in the cabin, snipped the GREEN/BLACK and BLACK/GREEN wires from the TCM connector next to the clutch pedal, crimped and soldered in a 2 pin molex connector, and did the same on my WPT-721 clutch pigtail. plugged everything together, fired up the car, held the pedal down, in gear. no throttle blipping. :ylsuper:

https://cimg7.ibsrv.net/gimg/www.rx8...d070ca1673.jpg

https://cimg3.ibsrv.net/gimg/www.rx8...edd9f37940.jpg

Need help
 

I’m doing this swap and was wondering if there a way you can contact me plz help

Help with...what? I don't mind helping, but we need *something* to work with.

What's going on?

I still have the 8. At least for a while longer. It will be visiting the local dealership on Monday to get all the outstanding recalls processed (front control rod / bushing or similar, both front air bags, and the fuel pump).

I might have a buyer lined up. It is really hard to let her go, but she's been sitting the driveway for far too long and needs a good owner.

Hi guys.
I'm about to swap 5MT -> 6AT and wanted to ask several questions:
1) Are powerplant frames same on MT and AT? I know that 5MT and 6MT frames are the same but are MT and AT?
2) Same question about the driveshaft. I have a carbon fiber driveshaft on my 5MT. Do I need to get metal one from 6AT (or 4At if they are the same) or I can just use mine

1. PPF is the same on all cars.
2. Driveshafts are dimensionally identical. Use the carbon fiber one if its in good shape

BigBadChris, thank You.
One more question: is the spline part of the driveshaft same too? Will MT spline yoke fit AT?

That I do not feel confident answering. I had a local rotary shop do my swap! That being said, I believe the Original Poster indicated that he used the (heavier) AT driveshaft on his manual swap without issue.

Wait, if you have the 5-speed, that means it's a 4-port, right?

I don't think there would be an ECU that would work with both the 4-port engine and 6AT. The 6AT was paired with the 6-port, so you would need the 6-port engine as well. The 4AT was paired to the 4-port engine.

BigBadChris, thank you for the information. I've already ordered a 6AT from USA, it would take a month for it to be delivered to my place. But I haven't ordered a driveshaft and a powerplant frame. Hope mine will fit otherwise it will take me a month more to get right PPF and driveshaft.


UnknownJinX, you are right. But to be honest i must say I'm swapping piston engine using stock 6AT transmission from RX-8/Miata and Miata TCM (it has the same CAN data transferred between ECM and TCM but more suitable for piston engines shifting map). The trick is I don't want to face issues fitting non-RX-8 transmission to RX-8 frame and also I don't want to remove RX-8 powerplant frame facing issues with rear diff case mount and weakened body frame.

Excellent work on the rev blipping guys!
I've just done a Auto to manual swap in the UK on my Black Cherry JDM 4 port Auto.
Kept the 4 port engine as running great and only 50k miles with great compression. Fitted a 6 speed manual gearbox. UK ECU, UK engine loom and ABS brain.

...only issues were
1, no power to starter motor (as per previous posts) we sorted this with an additional wire from the relay to the ignition.
2, the revs blipping to 1200 rpm when stationary and in-gear with clutch down.

Will now run the work around as per your posts.

Update - clutch wired in and grounded and the rev blipping has gone away - all good.:worship:

By the way - I had a dyno run earlier in the year as an auto and the results were predictably bad, with the manual gearbox on and no other mods (same stock intake, exhaust etc) it pulled 20% more torque and 15% more hp at the wheels - all measured on the same dyno which runs on the rear wheel hubs. So the swap over is well worth it.

I understand the want to run a 6 speed instead of a 5 speed, but for a 04/05 AT wouldn't it make it at least a little easier to put a 5 speed in it? Both 4 port motors as far as I'm aware, so maybe the AT ECU would play nicely?

PC being slow I asked this already didn't show me tho

It's been done... there's a (related) thread about it.

it was fun (but i felt bad for your wallet) watching your car transform over the years shell

I swapped an AT 6 port to a manual transmission, and I will say it’s a lot of work. You will need to change the transmission, starter, clutch, flywheel, proper harness and ecu if you wanna do it right, you’ll need the clutch pedal and linkage, the slightly smaller manual brake pedal (for clearance; or you can cut the regular one), there’s two clutch switches that need to be put in with the pedal, and you will likely have to swap out the ignition switch or rig something up because there’s a switch in the parking gear on the automatic selector so you can’t start the car unless it’s in park, it connects to the bottom of the ignition switch. And last but not least the shifter itself and the guage cluster will also need to be swapped.

it doesn’t make a big difference because regardless, the ecu doesn’t receive any of the signals it normally does from the automatic transmission because the manual ones don’t even have the connections for the automatic harness to connect to.

Would the manual harness hook up to the auto ECU? I don't see why not, but I haven't been hands on with a manual 8 ECU/harness

When I had the website rebuilt and hosted on a new platform, the old pics/directory went away and all the forum writeups with pic links went down.

I still have all the pics in folders backed up on my computer. If some mod etc. wants to take the time to upload all my pics to the forum somewhere then go back and edit all the posts and re-link the pics in order I will gladly supply the pics for you to do so. It's not something I have the time to do at this point.

That would be greatly appreciated, if any mods are still going through here. Worse comes the worse I'll use a JDM ECU

It will but it might have issues because it is not receiving info from the automatic tranny inputs/outputs. The engine should still run but it’s better to use a manual ECU. Speaking of which there is also an anti theft system consisting of the ECU, a keyless entry module (located under the passenger dash), and the ignition switch, if these parts are not all from the same car with matching programming the anti theft system will immobilize the car and it will not crank or start without some sort of bypass.

That's why I figured the auto ECU would be easier to use, because it's already be paired to the parts in the car. I guess I'll see for myself, if anything goes wrong I can use the ECU that comes with the motor I'm getting, and have it reprogrammed using FORscan or what have you.