# engine question **URL:** \ **Category:** Hybrids & Advanced Aftermarket Engine Performance\ **Created:** [November 29, 2001, 4:36am UTC](https://forum.g2ic.com/t/engine-question/18707 "2001-11-29T04:36:02Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![system](https://forum.g2ic.com/user_avatar/forum.g2ic.com/system/32/1_2.png) [@system](https://forum.g2ic.com/u/system)\ **Post date:** [November 29, 2001, 4:36am UTC](https://forum.g2ic.com/t/engine-question/18707/1 "2001-11-29T04:36:02Z")
I’m planning on putting a B18C into my 91’teg, and was wondering…do I have to reverse the IAB’s polarity to give it a 12V signal. Anyone? Thanks ---
**Author:** ![Colin](https://forum.g2ic.com/user_avatar/forum.g2ic.com/colin/32/16_2.png) [@Colin](https://forum.g2ic.com/u/Colin)\ **Post date:** [November 29, 2001, 8:10am UTC](https://forum.g2ic.com/t/engine-question/18707/2 "2001-11-29T08:10:02Z")
one question, whats an IAB? oh, and even though i don’t know what one is, i’m pretty sure the answer is no. Dan’s swap guide is very complete, and he never mentions anything about that–so i assume its nothing you have to deal with. ---
**Author:** ![JETSPD1477](https://forum.g2ic.com/user_avatar/forum.g2ic.com/jetspd1477/32/64_2.png) [@JETSPD1477](https://forum.g2ic.com/u/JETSPD1477)\ **Post date:** [November 29, 2001, 8:19am UTC](https://forum.g2ic.com/t/engine-question/18707/3 "2001-11-29T08:19:48Z")
Reverse the polarity? One wire is a 12v source… and the other wire is supposed to lead to the ecu which rotates -12v to actuate the IAB switch. You can’t use a 94+ GSR ecu in your car unfortunately. You can use a PR3 ecu and a RPM switch to actuate the IAB, or you can just buy a skunk2 manifold and eliminate the dual plenum manifold all together. HTH ---
**Author:** ![system](https://forum.g2ic.com/user_avatar/forum.g2ic.com/system/32/1_2.png) [@system](https://forum.g2ic.com/u/system)\ **Post date:** [November 29, 2001, 10:29pm UTC](https://forum.g2ic.com/t/engine-question/18707/4 "2001-11-29T22:29:36Z")
Cool, the reason I asked about the IAB is cause I am going to use a OBD-1 from a 94+ teg in my car. I’m having a guy build me a custom wiring harness so it will work. I don’t know if that changes the fact that I need to reverse the polarity or not? Thanks a lot for your help! Mark ---
**Author:** ![Colin](https://forum.g2ic.com/user_avatar/forum.g2ic.com/colin/32/16_2.png) [@Colin](https://forum.g2ic.com/u/Colin)\ **Post date:** [November 30, 2001, 12:56am UTC](https://forum.g2ic.com/t/engine-question/18707/5 "2001-11-30T00:56:05Z")
custom wiring harness? please let me know about this, shoot me an email at [clenkeit@ucsd.edu](mailto:clenkeit@ucsd.edu) i’m planning on swapping a b17a into my 91 and in order to pass smog i need to run an obd1 ecu. oh, and unless you are in my situation and need to pass smog i highly suggest that you just run the car as non obd. It will save you some $$, help performance (the skunk2 manifold is much better than the stock b18c1 one), and be MUCH easier to do the swap. but again, please let me in on the details about this custom wiring harness. I was looking at the pin outs for non obd and obd1 and they are VERY different, it seems like a converter would be really hard to make. thanks ---
**Author:** ![system](https://forum.g2ic.com/user_avatar/forum.g2ic.com/system/32/1_2.png) [@system](https://forum.g2ic.com/u/system)\ **Post date:** [November 30, 2001, 3:48am UTC](https://forum.g2ic.com/t/engine-question/18707/6 "2001-11-30T03:48:01Z")
Alright, well I posted a thread days ago on [Bseries.net](http://Bseries.net), and am got a response back about a guy in Florida that makes custom wiring harnesses. What I am having him do, is make a converter harness from Molex plug B and C in my car to plug into the Molex Plug B and D slots on the OBD-1 Ecu. I paid 250 for it, and he is working on it right now. I am doing it cause of smog, and plan to either put the JG Edelbrock intake on, or a JRSC. I’ll let you know more as it develops. Plus, I rather run an OBD-1 ECU so I can get a tuned ECU from Hondata or Locash. Later ---
**Author:** ![system](https://forum.g2ic.com/user_avatar/forum.g2ic.com/system/32/1_2.png) [@system](https://forum.g2ic.com/u/system)\ **Post date:** [November 30, 2001, 3:49am UTC](https://forum.g2ic.com/t/engine-question/18707/7 "2001-11-30T03:49:59Z")
I’ll let you know exactly what the setup is when I get my harness. I looked out the pinouts as well, and was way confused, but people I talked to on Bseries, said this guy has built harnesses like this before. ---
**Author:** ![Colin](https://forum.g2ic.com/user_avatar/forum.g2ic.com/colin/32/16_2.png) [@Colin](https://forum.g2ic.com/u/Colin)\ **Post date:** [November 30, 2001, 4:48am UTC](https://forum.g2ic.com/t/engine-question/18707/8 "2001-11-30T04:48:05Z")
wow, this is awesome. jdmhondaparts has something on their site about a non obd to obd1 converter, but its not available yet. do you have the guy’s email addy? i’m quite confused as to how its even really possible without tearing out everything. Do you know if what you’ll be getting is a whole wiring harness or if its just a connector which will allow an obd1 ecu to plug into your existing wiring harness? oh, and when you get it i’d love to see pics if you could get them, too bad you’re not local! thanks again. ---
**Author:** ![system](https://forum.g2ic.com/user_avatar/forum.g2ic.com/system/32/1_2.png) [@system](https://forum.g2ic.com/u/system)\ **Post date:** [November 30, 2001, 5:25am UTC](https://forum.g2ic.com/t/engine-question/18707/9 "2001-11-30T05:25:27Z")
wow, [jdmhondaparts.com](http://jdmhondaparts.com) is going to sell one too! do you have a link, casuse I wanna check it out, and price. Oh and I will definetly take pics with the digicam and send them to you when I get the harness. I got your email saved. Later ---
**Author:** ![Colin](https://forum.g2ic.com/user_avatar/forum.g2ic.com/colin/32/16_2.png) [@Colin](https://forum.g2ic.com/u/Colin)\ **Post date:** [November 30, 2001, 6:33am UTC](https://forum.g2ic.com/t/engine-question/18707/10 "2001-11-30T06:33:17Z")
i just got your email, thanks. i’ll anxious to hear how this turns out. here is a link to the jdmhondaparts page: [http://www.jdmhondaparts.com/wireharness.htm](http://www.jdmhondaparts.com/wireharness.htm) however i have no idea when it will actually be available. thanks again. late colin