CATEGORIES FOR ARTICLE LINKS BELOW

Swapping the Acura RL Manual Transmission to a TL 6 speed manual

Contributed By: Enginebasics.com

Project is taking a course change.  I was going to get the car all up and running using all of the factory components.  In the end though I would be left with a 305 hp automatic SH-AWD swapped civic.  Not bad right?....... but not what I really want.  What I really want is a fire-breathing 700 whp monster.  Also I like to row my own gears.  I don’t care how much faster an automatic is as I just feel too disconnected from the driving experience when there isn’t a 3rd pedal and a shifter to slide around.  Some might argue the RL is a tiptronic so I could move a shifter, or push buttons on my steering wheel, but these are just things people who can’t drive stick say to make themselves feel like they are equally involved in the driving experience.  The other side of that excuse is they wanted “ALL OUT PERFORMANCE” and the auto outperforms the manual all the way.  Look, we all know this.  Porsche recently discontinued a manual transmission in its GT3 model 911.  In an interview with one of the Porsche big wigs they asked why there was no manual transmission option for the GT3 anymore.  He responded that “the GT3 is for all out track/car performance and you just not going to get that with a manual transmission anymore”.  Well said sir.     Another Example: F1.  When they were permitted to have traction control and paddle shifting the track records started to get set all over the place, but ask any of the drivers who went through that transition and they all said they missed the days of the turbo monsters of the 80’s with no traction control and a manual transmission.  Watching old videos of Aytron Senna trying to control those MONSTERS is so intoxicating, but hey I get it.  Different strokes for different folks, and for me I am willing to give up performance for an experience, because in the end driving should be an experience.
So I picked up a 6 speed AWD manual transmission from a 2012 Acura TL and will be trying to swap it on to my J35a8 2005 Acura RL block.  Research has shown it should be no problem bolting to the block but who knows.  The other problems that will be introduced are:

1.  Will the RL starter work, or will I have to find a TL starter?
2.  Will the transmission mounts to the RL sub frame be deferent than that of the TL?  (most likely)
3.  Will my civic master cylinder work?
4.  Will there be enough room on the RL sub frame for the TL manual transmission transfer case?

Anyway, that is a start of some of the problems I could run into.  At this point it’s nothing I didn’t think I couldn’t handle or solve so I picked up a manual transmission.  These transmissions are SUPER RARE, but lucky for me they don’t really break on stock TL’s and so no one really wants the AWD 6 speed.  Even guys that think they want one to do a FWD swap and will leave the transfer case off still don’t want one, since they are heavier than a 07-08 TL Type S manual trans and also don’t have an LSD like the 07-08 TL does. 

So there is going to be some work to get the manual transmission to work, but honestly it is going to be a lot less work than trying to get the auto to work.  Here is the problem that would keep most people from attempting this.  The SH-AWD has a rear mounted ECU that controls the rear diff to engage the SH awd.  It is one of the most sophisticated AWD systems on the market and it is controlled through this rear ECU that communicated to the RL instruments cluster and then on to the ECU through the CAN-bus system.  There is no way I’m going to decipher the CAN communication coding and get anywhere there, so normally no one can do this swap, because then the AWD won’t work.  This means people have to use the stock ECU and all of the stock sensors and cluster, which limits you on what you can do and the wiring is INSANE.  I’m going to go out on a ledge here and try and control the rear differential with a standalone ECU.  How you ask?  I don’t know yet.  I have some ideas though that again, I am pretty sure will work so I’m going to do the investment and go for it. 

Now for some really good news.  With the elimination of the factory ECU the wiring gets WAY simpler and starts to look more like a regular swap.  I just need to merge the factory harness with the stand alone ecu’s harness.  No more trying to use the acura RL instrument cluster or the RL’s  TCU ECU or the rear differential control ECU.  I will still need to run wires to several sensors and need to engineer a rear control unit to control the rear differential, but I think I can tackle that.  That’s what is going to be the make or break of this project is: can I get a standalone ECU to accept 7 sensor inputs and interpret that signal and come up with a logic that can then drive a rear AWD controller that can then drive the rear differential.  Oh it’s going to be fun people.