USDM B18b auto to JDM B18c auto swap

We may earn a small commission from affiliate links and paid advertisements. Terms

ReptilianLava

New Member
I have a USDM 1995 LS (B18b) Auto Integra. I've bought a JDM (B18C) with the Sir-G Automatic transmission. These of course were only sold in Japan. They were never separated and still has all the wiring attached except the wiring harness that plugs into the ecu. I currently have the P75 LS ecu in the car, but I need the JDM P72 for the Vtec to work. The only problem I'm encountering is that the P72 (Auto version) has 4 wiring slots instead of 3... Does anyone know where/how to get the wiring to match there? It seems that either harness will work except the one that goes through the firewall to the ecu... Anyone do this before or know how it's done? Thanks.
 
Sorry but I forgot to say that it's all OBD1, everything is. I know I can run a Vtec controller and just use the P75 but then I would lose my high RPM range due to the LS RPM redline. I've heard of people (few) doing this swap successfully but none have said if they used a JDM P72 Auto OBD1 and how they made it match up.
 
Your worried about redline in an automatic?

How many times do you see an auto shift anywhere near redline?

If your that set on auto, use the Vtec controller to adjust it,

or switch manual.
 
If anything I shift my auto manually if I'm ever trying to push it that far, I decided to leave the auto in it because I'll be driving this as a daily driver to college all the time so I know I'll get tired of constantly shifting especially in traffic. I think I can just wire in the tcm that I already have in the car and use it to shift since it relies on the ecu to know when to shift. The P72 auto uses an internal tcm, hence 4 inputs instead of 3 like normal obd1 ecus. So I'll be trying that first. If it doesn't work for some reason I'll have to wire my own to the ecu's tcm slot I guess... Besides if I feel the auto holds it back too much (it shouldn't too much Sir-G tranny) I'll either put a torque converter in it or switch to manual later on.
 
If anything I shift my auto manually if I'm ever trying to push it that far, I decided to leave the auto in it because I'll be driving this as a daily driver to college all the time so I know I'll get tired of constantly shifting especially in traffic.

Are you used to driving a stick? If you're used to it, then it shouldn't bother you to drive it frequently. And really, there'd be no point in you shifting this transmission manually. If it's designed to be used with a B18C (gearing and such), then just let it shift itself. It can change gears faster then you'll ever be able to...
 
Well I know how and I'm decent at driving stick but my main car (this integra) has always been an auto. Currently I'm driving a stick while I'm working on this. So I'm not exceptionally great at it. This is the ecu that was originally designed for this engine, so I it should shift accordingly. The only thing I'm worried about is that I'm probably going to use the external tcm that's already in my car so I don't have to rewire my harness to fit the internal one in the ecu. Will the external tcm differ from the internal one or are the shifting points based of the ecu not the tcm?
 
the way u do it is get a 94 acura ls auto ecu,have it chipped for v-tec and add gsr map. you will also need the control module from the 94 integra...then you wire it up like it was in the integra basically adding ur v-tec wires....it will shift like a standard u control each gear......mine has ran many 5 speed cars ..i couldnt find a wiring diagram for the 4 plug jdm ecu thts y i used the integra ls stuff ......my dude is the wiring god so if you have any probs wiring it up feel free to ask and ill help however i can......many people doubt my automatic,and many people have been smoked.....xenocron tuning solutions is who did my ecu...hes a beast. but good luck it took us 3 months to figure it all out but trust me i am very happy with the results! baddest auto iv ever drove:D
 
and u should have the ecu and control module in it already so it should b easy,just have to add a few wires for v-tec and a couple on the tranny.
 
the way u do it is get a 94 acura ls auto ecu,have it chipped for v-tec and add gsr map. you will also need the control module from the 94 integra...then you wire it up like it was in the integra basically adding ur v-tec wires....it will shift like a standard u control each gear......mine has ran many 5 speed cars ..i couldnt find a wiring diagram for the 4 plug jdm ecu thts y i used the integra ls stuff ......my dude is the wiring god so if you have any probs wiring it up feel free to ask and ill help however i can......many people doubt my automatic,and many people have been smoked.....xenocron tuning solutions is who did my ecu...hes a beast. but good luck it took us 3 months to figure it all out but trust me i am very happy with the results! baddest auto iv ever drove:D

Are you disabled or something? Can you not drive a stick? Sorry, I just cannot for the life of me figure out why anyone would prefer to have a slush-box hooked up to their dual-cam VTEC engine. And 3 months to make it work? For all that trouble you could have just swapped it to manual...
 
Are you disabled or something? Can you not drive a stick? Sorry, I just cannot for the life of me figure out why anyone would prefer to have a slush-box hooked up to their dual-cam VTEC engine. And 3 months to make it work? For all that trouble you could have just swapped it to manual...

Wurd WTF?!?!?
 
u drive wht u drive ill drive wht i drive. it runs with the best of them homie!! once i put a stall in it ill race any 5 speed from a dig!! im just tryin to help homeboy so he doesnt have to go through wht i did!! yall would have the same reaction everyone else does ....trust me!!
 
my buddy said the same thing with his 5 speed gsr,all his bolt ons and mine bone stock ran his shit...hes not the only one tht doubted my shit :)
 
Back
Top