I was thinking about whether or not it'd be possible to put the ECU from the 49state civic VX and putting it into the 1996 civic HX. I realize there are quite big difference between the two cars but I was also made aware that despite the HX having a 1.6 litre engine, mini-me have been done with the head. That you can apparently put a head from a 1.6 litre engine and put it onto a 1.5litre engine and vise versa. How is this possible anyhow? In those configurations, would you stick with the original ECU or put the ECU that came with that head? So I figured that if you can do something like this, then maybe I could use the 49 state VX in a '96-'00 HX.

 

what?

 

obd-2 to obd-1 conversion harness, if I'm understanding the question correctly.

 

Wait, so you're saying that all I would need is an OBD-2 to OBD-1 conversion harness? That this WOULD in fact work?

 

If you're doing this because you saw on the Fuel Economy site that the VX gets over 50mpg and you want your HX to get the same MPG by swapping ECU's, its not gonna work lol... It wouldn't work anyways because the VX is OBD1 and the HX is OBD2, but besides that, the motors are different in a couple aspects..


Also, read this it's a good FYI and is the very top post so you prolly shoulda read it already even tho im assuming you haven't...
https://honda-tech.com/zerothread/878010

 

I understand I wouldn't get the same fuel economy, but I do believe that swapping in a Fed 49 state VX ECU would yeild a significant improvement in fuel economy over the HX's ECU which is worse than even the california VX ECU. Also isn't the OBD version determined strictly by the ECU itself? I know that going from OBD-I to OBD-II should be nearly impossible but going from OBD-II to OBD-I should be possible. OBD-I has fewer sensors which would mean the OBD-I ECU would have less needed to be hooked up over the OBD-II ECU.

I believe that if I were to put in a CX/VX tranny and use a FED 49 state VX ECU, I would be getting much better fuel economy than had I left the HX alone.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by imzjustplayin &raquo;</TD></TR><TR><TD CLASS="quote">I understand I wouldn't get the same fuel economy, but I do believe that swapping in a Fed 49 state VX ECU would yeild a significant improvement in fuel economy over the HX's ECU which is worse than even the california VX ECU. Also isn't the OBD version determined strictly by the ECU itself? I know that going from OBD-I to OBD-II should be nearly impossible but going from OBD-II to OBD-I should be possible. OBD-I has fewer sensors which would mean the OBD-I ECU would have less needed to be hooked up over the OBD-II ECU.

I believe that if I were to put in a CX/VX tranny and use a FED 49 state VX ECU, I would be getting much better fuel economy than had I left the HX alone. </TD></TR></TABLE>

Nope wouldnt work, but I understand your educated guesses and where you're coming from with some of the ideas you've given...

It's a lot more of a difference than just a couple wires, in reference to OBD-1 vs OBD-2... Swappin an OBD-2 motor into an OBD-1 car is just as basic as using ur stock OBD-1 Distributor and Fuel Injectors, but swapping and OBD-1 motor into an OBD-2 car is quite a different ball game... Fuel economy wise, if you have an HX you're doing pretty good on MPG "31 city about 41 highway" compared to the VX which gets about "39 city and 50 highway"... I'd say find the for sure differences in both setups and go from there, i've never had a VX or HX, I like my gas hog boosted vtec motors lol...

 

Has anyone swapped an OBD-I engine into an OBD-II body/chassis/whatever? How dependent is the car on the ECU? How many functions of the civic are driven by the ECU itself and not other computers or somesuch? Would an ECU from a JDM civic pass emissions here in the USA? Cause I was under the assumption that if the car is OBD-II, when doing emissions, the technician doing the smog check hooks up to the OBD-II port.





Modified by imzjustplayin at 8:17 AM 6/4/2008