so question, since you got an obd2 engine would you be able to pass emissions with it? i have been wanting to do this on my accord(same year) but i never wanted to go through the odb1 route because of the whole emissions thing.
I am in the same boat as you. I live in Texas and don't have any connections to pass with obd1 emissions either. I will remain obd2. I did get a p72 ecu for future use but I'm in no hurry.
This is probably the hardest part of the whole build. I'll list what I know you will or at least what I will be doing to avoid check engine lights and to pass emissions.
-Get the ecu that matches the motor and trans your putting in your ride. Best to probably shop and get a motor already obd2, just a suggestion. The ECU I got is from an obd2 M/T prelude (p5m I think). Stick to the US ecu for emissions. Learn the ecu code your looking for before shopping.
-Get an obd2b to obd2a adapter harness for your ecu plugs to match the prelude ecu.
-Take the ECU to a dealer or locksmith with the ability to reflash your new ECU's immobilizer to match. Yes, it is possible and I was quoted at or a little above $100 from a local dealer and locksmith. The lockskith will come to the house for $125 and do it. I asked the guy if I have to start the car when he does it and he said no, just that the key will need to be in the on position. I am going in a few days to do this with my current f23 motor still in, I'll be sure to confirm.
-next, the wiring. You have to worry about the distributor, IACV and IAB.
-The distributor. The accord has a 4p plug and that's it. The prelude has 3 plugs: A 4p and a 2p on the distributor and a 4p plug (with only 3 pins) on the coil. So it's 4 prongs vs. 9 prongs. Well I belive I was able to figure that out last night and I will post up a decent diagram as soon as I double check it. Works out that really there are only 4 prongs (wires) that leave the area, the rest connect the coil to the distributor and/or power to the distributor icm or coil. Don't quote me on that yet, I will get this drawn up soon.
A jdm accord h22 4p plug distributor may work but not positive. After studying the wiring diagram of the US h22 coil and dist it makes since to me that it could work without getting a check engine light. Ok, next.
-You will need an extra engine wiring harness. Preferably the h22 but I got my plugs from a 96 accord harness. Accord is probaby cheaper too, if your just going to cut into it.
-From there you need to unpin your accord distributor plug and set it aside incase you decide to swap motors again someday. From there, I'll post a diagram soon...
-IACV is next. The accord has a 3 wire, the prelude is 2. One wire to ecu, one to a 15A fuse. I'll verify and post diagram soon.
-IAB secondary butterflies. 2p plug, one wire to ecu harness the other is power from somewhere. I'll let you know.
-I will also post my method of running and pinning the wires I used from the extra engine harness.
I am right in the middle of researching all this stuff so I can do this swap right in one shot with no or minimal issues. I'll try and get diagrams up soon. I have not found a decent obd2 h22 swap thread I can fully trust so I have just been going to the source, the service manuals, for electrical, specifically. Though I have learned a ton from other h22 swap threads, there just aren't that many obd2 ones for one, much less ones that go very far into the electrical side.
Hope this gets you started or a little more confident to attempt the swap. I'll hopefully post the diagrams soon. It is the holidays though so be patient with me please.
L