Honda / Acura K20a K24a Engine Forum banner

k20a3 transmission into k20a2

11522 Views 3 Replies 4 Participants Last post by  Vtecmdnss
I have a question for any that may know. Pardon me if it's been asked already, but I didn't see it.

I have narrowed the potential choices for my EG swap down to 2 choices:

1) 2001 Integra GS-R (or LS for supercharging later)
2) k20a3 from 2004 RSX

I want the a3 only because of the transmission. It is going to be a daily driver, so I want the convenience of the automatic during stop-and-go highway traffic (a big problem in the California Bay Area), with the sport shift when I want to really drive the car. I don't mind not having the extra 40 horsies as long as I have this feature, but still... I can't deny the appeal of having more power.

My question is, can the transmission from the base k20a3 be mated to the k20a2? Is there anything from preventing me from easily doing this?

Thanks for any input or advice.
1 - 4 of 4 Posts
wow,,,

actually both tranmission can be use they are the same only the different is one is 6 speed another iz sport shift... if you want to covert k20a3 transmission to k20a2 you must use the k20a3 tranmission computer box and the wiring also ....... you must take out the k20a2 tranmission wiring and tranmission computer box replace with k20a3 ,,,
bluebomber said:
I have narrowed the potential choices for my EG swap .................
My question is, can the transmission from the base k20a3 be mated to the k20a2? Is there anything from preventing me from easily doing this?
I believe Hondata can program the K20A3 Auto ECU to be used with the K20A2. Now for the real question, putting that mess in an EG.

If my wife or my niece came to me and said, I really want an engine swap but I want to have an automatic transmission. I would say, "Be very careful who you find to do that swap, it's difficult and very time consuming." They would say, "Can't you do it?," to which I would reply, "Sure, but I'm not going to. I don't have the kind of time it would take to do it right and then trouble shoot it until it ran properly as designed. Basically you would be buying a whole car for a donor and transplanting parts until it worked."

If you're serious about this swap, buy the RSX Service Manual and Electronic Troubleshooting Manual and spend a weekend going over the systems to see what's involved. The manuals will cost you about $110-120 but will save you either many hours or many dollars. If you decide not to do it, you can sell the manuals on this site in the classifieds.

Sorry for the bad news.

brian g
See less See more
Well im new to ur guys forum so hey all. I know im new here but when i read this post i couldnt help but reply.

1st Hondata claimes they cannot flash the auto ecu due to insufficient memory so really dont know if u can got hat route unless hondata kpro will work.

2nd as several people i know of have done the k20/a3/a2 head swap in such i know that the tranny will not nearly put the power to the ground anyone is looking for youll fall out of vtec in every gear and if u got a vafc or kpro to help that it still would not keep u from falling out of the power band. I know a guy with the a2 head on the a3 block and he has 197whp in his si. he ran a 14.6 with the old a3 setup and then ran a 14.5 with the a2 setup because the a3's tranny couldnt keep him in the powerband. so thats something to think about.

3rd well its an automatic and i need not say more about that.

but to answar ur question yes it can be done but ull be getting beat by gsr swapped eg's left and right.

Please Dont flame me cause im new and im just trying to help If im wrong feel free to correct me.
See less See more
1 - 4 of 4 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top