I have an 04 rx8 that is in need of another transmission. my question is do the 2009 transmissions bolt up? are any of the sensors different? I guess more importantly is the transmission any stronger?
Thanks

 

This has been discussed before:
https://www.rx8club.com/series-i-tec...es-1-a-219697/

Post #3 I outline what I had to do in order to get this swap to work.

 

I have done this in mine and it is TOTALLY worth it.

The S2 gearbox isn't perfect but it's a damn sight better than the S1 gearbox.

A quick bullet-points list of changes:

• You'll need an S2 shifter but you can keep your S1 **** if you don't mind R being in the wrong place.
• There's a spacer plate that goes between the S1 engine and S2 gearbox.
• The pigtails for the neutral and reverse switches are different. You can either cut the connectors off your S1 gearbox and splice them into the S2 wiring or cut the connectors off the car and gearbox and wire in your own.

Parts (from my order history):

• LEVER,CHANGE Part No : P610-17-510C
• MANUAL T/MISSION CPT. Part No : P6Y1-03-000
• BUSH,CHANGE Part No : P611-17-492
• PLATE,END Part No : N3R1-10-901

I was able to do it for ~$2200 shipped from MazdaSpeed Motorsports Development.
You could probably save some dough buying a used gearbox but I don't recommend it.

Other than that, it bolts right up. Pay close attention to the PPF alignment and torque values. Also, don't be like me and a buddy: make sure you keep the switch wires securely fastened away from the exhaust. I got lucky and only slightly melted the connectors but my friend had his fuse together and short out while on track.

The process is relatively straight-forward if you have the usual tools (metric sockets, wobble adapters, torque wrench, 4 jack stands, and a jack). A friend is very helpful but it's theoretically possible to get it done alone.

If you've got the transmission and engine separated, it's worthwhile to just do the clutch whether it needs it or not.