My 88 crx-z1 project
 

Hello. My name is Alex and i've been a member for a brief period of time here at gassavers.com. I recently bought a 88 crx si, no a/c, condenser, heater, or even an engine and its wiring harness (only an 89 FI resistor box). it came with an si transmission and with all the linkage (may need some restoring), the radiator, and all the wiring harness inside the dash. it has been in someone's driveway for over a year, has no rust, but a lot of dry dirt in the engine housing.

My plan is to do an HF+z1 swap. so far i've purchased a CA HF tranny, still have my si starter (dunno if it may work with my hf tranny, but it's a direct fit), p07 ecu, hf front suspension with hubs, disc brakes and calipers (hf assembly is lighter and smaller than si), hf driver's side drive shaft (the other is busted), and some cosmetic stuff for cheap.

anyone that has done this swap, can you give me a complete list of what i need? most of the seals are corroded, so without a doubt i'm going to need tons of seals. i'm planning on buying new engine mounts too to avoid future headaches, but i don't know which mounts to use (88-91 or 92-95).

i know i need a engine wiring harness, and i might try to find one in the junkyard (might just find hacked stuff but it's worth a try).

so any available info will be great.

Welcome
 

It's gassavers.org. :D

Welcome to the site. I have a 97 civic hx. Props on the reworked SI. Do you have the California hf tranny? Someone here will definitely be able to help you.......

the starter will work with the tranny, i'd bet it will work with the flywheel, my 90 hf starter works with an 88 flywheel even though it's a different size than a 90 flywheel.

lol.. sorry about that... Gassavers.org. i was looking at Matt's swap. seems like he didn't need an FI resistor box, but i'm short an si wiring harness. and yes, i do have an hf california tranny, so the 5th gear is short and will go 50-55mph at 2200rpm... sucks, but if it's possible, i might buy a non-california 5th gear and swap it out (if possible) to get it down to 1700rpm or so.

I have an entire '90 CRX Si Wiring harness. This harness covers EVERYTHING from the ECU through the underside & hookup to the dashboard, through the firewall & all throughout the engine. This IS the MPFI that the Si & HF models use. The DX used the other type. Seriously though, if you need a wiring harness for a CRX, this was just removed a week and a half ago...by me. This harness even runs throughout the body of the interior of the car, to the rear lights & all. It's all here. Just give me a shout.

I'm unsure of the specifics, but I know that the 88 is different in spline count from the 89-91. You might have to get new axles if you have the wrong combo.

Hopefully someone else can clarify the specifics. It's been over a year since I thought about this problem, so I can't remember the details.

The starter will work - all D-series flywheels have the same # of teeth.

As Matt said, make sure you get the correct clutch for the transmission - spline counts do vary.

If you have an Si chassis, the HF axles will not work - you will need Si/DX axles. If you're slick, you may be able to use the HF axles (busted or not) as cores for your new Si/DX axles - just pay the core charge, then bring the HF axles up later that day and they'll refund the core. If you bring in the axles while you buy the new ones, they'll see that they're slightly different and won't swap them for you.

Also the p07 will require you to do some "creative" wiring...Along with an OBD-1 conversion you'll need to wire in the 5-wire 02 along with the EGR provisions. The Si engine/cabin harness has neither of these.

Another creative suggest you may want to take is attempting to find an HF ECU that will plug into your Si and run for the z1 most part...minues VTEC and you'll still need to wire in the EGR functions, however it will cut down on *some* of the complexity of your install.

Factory HF's were know for 50+mpg without the "lean-burn" tomfoolery of the VX(D15z1/p07)...It would still be and interesting swap.

I've personally done a Z1 + Dx tranny swap into an 89 hatch with obd-1 conversion. I ran Z1 fuel/timing maps on an p05(CX) ECU with a regular 1-wire 02 sensor. With A/C on, 4 people and all thier luggage for a weekend trip it got 40mpg....Without driving it gently.

Good luck guy

I was able to find soem info about compatibility at autozone.com. You can select both combinations and then make sure that the same part numbers are used on both to assess compatibility.

This wiring took me the better part of 2 weeks every night. Thank god my wife is understanding of my hobbies.

I would suggest getting a obd0->obd1 conversion harness from rywire. Just tell them exactly what you want. you're going from a pm6 to a p07. They'll get you EXACTLY what you need. This will still require some creative wiring on your part, but everything will be laid out for you.