has anyone tried using a a/t jdm p72 obd1 ecu on their crv-tec? the guy i bought my v from said he had one but couldnt get it to work right, i looked up the schematics and he was missing the a/t plug, he used a manual obd2-obd1 conv, so obviously it wouldnt work, but has anyone tried it wired right, does it work? i know the tranny will rev higher but other then that shouldnt it work

 

best find the jdm a/t obd2 p72 or p30

 

I did a little research on it a month or so ago. I'm pretty sure it will work. I emailed reywire and they were down to make a conversion harness for it

 

awesome, im fine with getting a harness and hoping it works, if not ill just keep what i have and just using a crappy vtec controller till i can find a dual ecu how to, thanks for the replys guys

 

I'm going to be testing a dual ecu setup hopefully this weekend, but probably next weekend. I will post a how to once the bugs are worked out.

 

awesome! i'd rather have a chipped cpu than a controller, better tuning options... ill keep my eye out for your post.

 

Thanks for continuing the quest, I'm swamped with work and can't afford to have downtime on my civic. Please let us know how it goes.

 

You can probably get it wired up correctly, the problem is the ratios are almost certainly different between the CR-V and GS-R trans so it will throw a code for incorrect gear ratio and will probably shift a bit weird. Even the USDM and JDM CR-V trans are like this and will throw codes.

 

I know this is a fact as I tried using a P2P on my setup and my transmission was from DX, it didn't shift right 2nd gear to 3rd and it threw a code for torque convertor lock up. But it still drove fine. My setup is the d15b 3 stage with a DX auto. I've had it running on two different ecu's and it works fine, eco mode kicked on (verified by the led indicator that I wired up). I just couldn't figure out how to get the tc lockup to occur. Hopefully Phil can shine some light on the mystery with his version of the dual ecu configuration.

 

I tried the opposite, P2E with an EX trans. It threw a P0715 incorrect gear ratio code. It shifted progressively worse too, it would take a while to throw a code, I think a couple of weeks, but it wasn't driven that much either, and it would start pretty good, then gradually shift more and more erratically. If you cleared the codes it work alright again for a while.

 

can you switch gears in a a/t like you can in a manual? make the b20 a/t have the gsr internals, thatd be dope (idk much about a/t's), my teg has a gsr 5 speed with the 5th from a LS for highway gas mileage, itd be cool to get a gsr a/t and put the gears into the b20s tranny if its even possible

 

You might be able to, you might have to swap valve bodies as well.

 

I might look into that, that would be cool i think have a gsr auto tranny inside a b20 casing so it would hopefully run right... might talk to my old shop I used to go to and see what he thinks and see what we can come up with

 

I think you're better finding the a/t awd tranny. i was told the gearing on those things are close to the b16. A guy on here did an awd 5spd swap in a del sol with the awd 5spd cable tranny from the 1st gen crv's. He confirmed the gearing to be close to the b16. So you can imagine what the auto crv could possibly be close to.

 

i got a awd a/t tranny, so close to b16 huh, nice to know- i may just keep the gearing then and just add some power to the motor. might try to swap out the 4th gear for something longer just for better highway mileage, and keep the short 1-3 for get up and go. might just leave it all alone too lol

 

What are you going to swap it out with?! :confused:

 

If you start trying to get into swapping individual gears you're going to throw codes for incorrect gear ratio.

 

well i was originally trying to figure out if I could use the odb1 jdm p72 auto ecu with my awd auto with vtec (b20 with gsr head), but the ecu would throw codes i guess if I used the ecu, so I was thinking about swapping internal gears with a gsr to get the ecu thinking it was a gsr tranny (but really keeping the b20 awd auto case for awd goodness), but if the tranny is close to b16 i may just leave it alone.

 

94eg8- that sucks. i now hate auto crap boxes again. lol

 

awd automatic gearing is not the same as a manual 5spd transmission. You're getting the wrong idea. I said the gear ratios are almost similar to a b16, that doesn't mean the gears are the same. Leave the awd alone and just run the automatic p72.

 

I've compared an obd1 a/t wiring diagram setup and it has almost all the sensors except for the linear solenoid. I'm sure it will shift fine with just the shift solenoid.

 

cool, i knew someone on ht would know something

 

Reason why I've been researching this is because I really wanna drop an automatic b20 in the ej sedan just for ***** and giggles, also to say its possible. Nobody has anything posted about it so everything is just theoretical and is an ongoing project. I haven't started collecting anything but if I come across a wreck crv its going down.

Sometimes posting up a question in the forums isn't really gonna yield an answer you're gonna like. At least do some researching by comparing wiring diagrams and sensors. Also not alot of people wanna share there knowledge because they had to do the research themselves and it cost time and money.

 

yeah i just figured maybe I could change internals pretty easily since the manual B series are all interchangable, I was hoping someone has done this in a auto to keep the casing the same. seams like a lot of work for pretty much nothing, but it would be cool to be different

 

So I read somewhere on pgfmi.org that a guy says to use the obd1, p74 automatic ecu with the matching TCM. This is from a 93 automatic integra. He claims because the transmission doesn't use a throttle cable to rev/match or shift that this works for the crv. Unfortunately he didn't go into detail but after looking at the transmission I confirmed his findings. Only question I have is what maps will work on a chipped p74.