Parts you will need to put a d15z1 engine into a 88-91 Civic/CRX
 

Hopefully someone else will need this information in the future.

Parts you'll need for this swap:

1) engine - d15z1 - should be easy to find one relatively cheap. You can also get them from a Japanese engine importer for around $500 shipped. When I speak of the engine I am assuming you have the intake manifold, throttle body, valve cover, all of the sensors, etc. If you are missing some of these things please let me know and we'll help you find some. Please also note that the Japanese engine does not have a spot for the purge valve solenoid, so you'll have to be creative. It's an easy workaround, so it's nothing to really stress over.

2) ECU - p07 - You'll need the p07 ECU from a Civic VX. You can get these for around $30 on various Honda forums. Since most people take their d15z1 and p07 ECU out of the VX to put in giant fast motors it's very common for people to have a p07 in their garage. there are two versions of the p07 ECU (California and non-California). I would recommend getting the non-CA version as it has lean-burn and will let you use a 5 wire oxygen sensor.

I'm unsure how to tell if it's CA or non-CA. If you can help please let me know and I'll update this post.

3) Oxygen sensor - you'll need a 5 wire oxygen sensor - this may come with your engine. You may also need to buy a new one. They cost around $200 from parts stores like Napa.

4) EGR Control Box - The Civic VX had an EGR control box that is unique to the Civic VX. It is a black box that is mounted on the firewall of the VX.

I will take a picture of this later so you can see what it looks like.

5) Catalytic Converter - The Civic VX uses a different style exhaust manifold than the regular civics/crx. If you have a Civic STD or a CRX HF odds are you have the right exhaust manifold (I've seen HF's with the wrong manifold though). As a result they also use a different catalytic converter. Hopefully you can source one of these from a forum member or someone who installed a turbo onto their civic. The catalytic converter/exhaust manifold/downpipe that you need for this (assuming you don't have a Civic STD or CRX HF) can be found in the following cars:

• 88-91 CRX HF
• 88-91 Civic STD
• 92-95 Civic VX
• 92-95 Civic CX

6) Downpipe, exhaust manifold - see above

7) transmission - you can keep your existing transmission with no worries. You can also use your existing clutch/flywheel if you want. If your clutch/flywheel/throwout bearing have a lot of miles on them, I would recommend replacing them while they are out. If your car is from 1988, your transmission/flywheel/clutch/axles are different from 1989-2000. Blame Honda for dropping the ball on this one. Keep that in mind when buying new parts, or swaping parts over.

8) wiring - You are going from obd0 ( or pre-obd ) to obd1, so wiring is going to be an issue. If you have the money, I'd recommend finding an engine harness from a Civic VX and sending it along with your engine harness to the guys at RyWire.com. They will make a new engine harness for you that is a hybrid of the two harnesses. It is important that you tell them exactly what you are doing so they don't give you the wrong thing.

If your Civic/CRX is a HF, EX, or a SI model you do not have to convert to MPFI (Multi-Point Fuel Injection). If it is not a HF, EX, or SI (your car will be a DX, STD, LX, or have no badge) you will have to make a few more adjustments to your harness. DPFI to MPFI wiring instructions are abundant, and we can point you to some if you need them. Rywire can also adjust your harness accordingly for an extra fee if you don't want to do much wiring.

If you cannot find a VX engine harness, you are going to have to modify your own harness so it will work. This is relatively easy, but will take a little time to get it done correctly. I would still recommend getting a conversion harness form rywire you choose this method because it makes things so much easier. If you go this route you'll have to find a number of plugs for an OBD1 engine. When I purchased my engine the plugs were already attached, so I was lucky. The plugs you'll need are:

4 obd1 injector plugs
1 five-wire o2 sensor plug - has 7 wires (can also use obd1 distributor plug)
1 obd1 distributor plug
1 obd1 distributor ignitor plug
1 plug for coolant temp sensor
1 plug for EGR valve
1 plug for EGR Control Box
1 plug for the vtec solenoid
1 plug for the vtec oil pressure

I will upload pictures soon of all of the plugs

9) If you already have a MPFI car (Si, EX, or HF) then you need to eliminate your injector resistor box to make way for the Civic VX 190cc injectors. It's easy to do, but i can't remember exactly how to do it. Will add instructions later.For now that is all that I can think of. I will update this post with pictures, more info, etc. as I think of it. If you can think of anything to add please reply to this thread and I'll add it to the first post.

Is it ok to use a regular 4-2-1 manifold with the Z1 setup, or do you have to use the log manifold that comes with it and the weird cat? I personally think it would be ok to use a regular Civic 4-2-1 manifold and a universal cat.

I do still have that weird cat from my VX up in my attic if anyone needs one.

krousdb might need it, unless he wants a new one.

I think that Honda made all of the FE cars with the same cat/exhaust manifold for a reason. My guess is because they wanted to have a faster reaction time to o2 readings.

Right, but a new one of these cats is ridiculous...like over $500 if I remember correctly.

krousdb just found a new one for under $200 on another site.

If a universal cat is a must, it might be best to use the barrel exhaust manifold and get a custom pipe made to connect the exhaust.

That's a good idea. The custom pipe wouldn't be that hard...if someone wanted to go this route, I could probably help out with the fabrication.

$200 is great...I'd like to see that website...I'm going to ask him about it.

good news....picked up a former VX harness, EGR box, and ECU (altho not a P07) for cheap yesterday. The shell was a '92 VX but the engine was either out of a DX or CX. I got the harness anyway as the seller said it was stock, although modified for the current engine. The ECU probably won't work (P05 or 06, I can't remember) but it didn't cost much. Did you ever get pics of the obd-1 plugs? If not I could go check my friend's stock VX but she won't be back in town for a few more weeks, no biggie. All I need now is a Helms, 5-wire O2, and a proper ECU, plus all the wiring conversions. Still, it's coming together. Mak

Mak, if you're looking for P07, I have one and am willing to make a straight up trade for the OBD-1 P06 (if that's what you've got).

ill check tonight and get back to you

Mine is a P09, which by my searching ( https://www.clubcivic.com/board/archi...p/t-43493.html)
is the same/similar to P06 and P05, all running CX/DX engines D15B7/8. I know not the difference it makes, but it seems they all are interchangable as long as it's manual to manual, auto to auto swap. Let me know, Mak