Is it possible to simply bolt a k20z3 transmission from a Civic Si into my 5-speed Acura CSX k20z2 and make it a 6-speed without an ecu? thx in advance!

 

Yes. You won't have the reverse lockout function but otherwise yes.

 

Is that bad?

 

I have driven both with and without lockout. The lockout is nice but not at all required.

You could tie it to your brake switch if you want a quick and dirty solution. Foot on brake to access the gate for reverse. Rather than the computer locking it out by speed.

 

My k20z3 transmission has the lockout solenoid attached to the shifter assembly but its missing the connector for the 2pins into that solenoid. Is it possible to wire that to my ecu somehow?

 

No idea on that one. If it was a copy and paste of hardware from the SI, maybe. Likely the output on the ECU isn't there or isn't programmed.

 

Does your 5-speed transmission have the VSS in the front or the back ?

 

Sorry what is VSS, is that the speed sensor? It's in the front, (same placement as the k20z3). Why do you ask?

 

Just making sure that your transmission change doesn't create another problem... a speedometer problem.

 

I just need to figure out if I can possibly wire the missing reverse lockout (2-pin) to my non Si/Type-S ECU and fix this problem.

 

Well if anyone's interested, after weeks of researching I came to the conclusion that it's nearly impossible to enable the reverse lockout solenoid even if the hardware and wire is provided since the ECU itself has been programmed for a 5-speed. You can use k-pro and other software to reflash it but I wanted pure OEM and didn't want to spend more money. Although the CSX may have a signal, I am going to check it later since something is unusual after the transmission swap.

 

Sorry about the long delay, So I did the transmission swap. Turns out the stock ECU has no signal for a reverse lockout. Even though I did manage to purchase a lockout solenoid. So essentially I'm driving with no lockout and so far once or twice I've accidentally shifted too far, but only a slight grind as I was careful but I can imagine the magnet inside is gonna be collecting shards ugh...

 

Last update, I should have posted this. I ended up swapping to a Type-S ECU (same as Si) and using an Si harness and swapping the tranny for an FD2. And also using FlashPro, I now have reverse lockout! Problem solved.

 

Way to go !!!

 

hey I read your messages in this journey,
I have 08 acura csx with 5 speed mt k20z2
So first of all u swapped 6 speed mt (from civic si or type s)
so is it this reverse lockout must do?
i read ur first try it seems drivable.
should do all of wiring and ecu transfer? Because I'm an 20yo guy to do try cheaper swap by myself.

My clutch is still good condition but I'm doing road trip Montréal to Toronto for studying, almost each month i doing Montréal to toronto non stop 6 hour driving. 5 speed mt is not enough, csx sherching 6th gear to go much smoother or much lower rpm, in 5th gear I'm driving 4000rpm or 4500rpm on the highway, vehicle's search 6th. I will be waiting your message .thank you for understanding