1990 Honda CRX Si D15Z1/HF Trans Swap Project - Fuel Economy, Hypermiling, EcoModding News and Forum

02ws6 · 11-28-2010, 04:44 PM

I have wanted to do this swap for quite sometime.. I think the idea of saving money on fuel is awesome and I plan to take a car that you don't usually see used for these swaps and would like to put a small twist on it..

I plan to drive this car everyday and want this to be a nice car that I want to drive not that I have to drive... So with that said, I will be putting A/C in this car and some nice wheels along with a lowered suspension..

I found the D15Z1 swap out of Charlotte, NC about 8months back for $400 and got everything I would need except the harness.. Just got the HF trans a few months ago for $150 out of Murfreesboro NC.. Just drug the car home on thanksgiving from Portsmouth VA and am somewhat happy with it but it will still need some significant work for it to be where I want it to be.. Interior is super clean and body is straight but needs work with both body lines and paint..

I can't wait to get this thing started and will try to take some pics as I go.. Any input, ideas or comments are welcome.. Im sure I will have many questions along the way Im sure..

This was the engine setup and how I snagged it outta charlotte.. I drove 320mi. one way to get this puppy..

Saw the FS add on this website! I had only been looking for about a year with no luck previously..

http://ecomodder.com/forum/showthrea...new-13085.html

This is the car I picked up..

An Interior shot.. pretty proud of this here.. Car has 160000 on the odometer..

MetroMPG · 11-28-2010, 07:01 PM

Pretty jealous of you guys who can find older, rust-free cars to turn into projects.

Looking forward to your build.

02ws6 · 11-28-2010, 07:31 PM

Ive been on the lookout for these parts for over a year now... Things have finally started to come together... living in the cold like you do, i imagine this older stuff is impossible to find though.. move to america..lol

MetroMPG · 11-28-2010, 08:07 PM

I assume you've seen Ben's D15Z1 lean-burn CRX project thread, eh?

(Since became an unfinished Insight drivetrain swap, but before that...)

02ws6 · 11-28-2010, 11:10 PM

If you are talking about crxmpg.com then yes... that was pretty much my inspiration..

02ws6 · 08-30-2011, 12:07 AM

Finally have an update after another year of gathering parts and info..

I've been through about 5 cars in the past year. Each one taking up my time and money lol... I don't have as good of a job as I did a year ago but Im doing what I can to not let that slow me up..

When I bought the engine out of Charlotte the owner (a honda enthusiast) informed me that the swap had about 240k mi on it... Pulled the plugs and found NGK-R's and thought this engine may have been beat on a bit since the last owner was an enthusiast and he was younger... The head looked good though and oil looked good too...

After talking it over with my pops and thinking on it a few weeks I decided that i'd go ahead and tear the engine down, put fresh rings and bearings in after the block has a fresh hone.

Really glad that I've gone through the extra trouble though.. Found that cyl #3 had significant wear on the rod bearing and had worn through the silver coating..

Bought an Engine gasket set from Rockauto among other parts and also had the cylinder head milled .0010 to help ensure seal over the block. Plus that little bit of compression may help. Also had fresh set of Valve seals put in, valve guides checked and the cylinder head cleaned.. Those intake valves were super gunky..

Other parts gathered were, D16z6 exhaust manifold, Shift linkage, front lower crossmember, and both CRX Si and Z1/VX engine harnesses..

Hopefully within the next week, me and pops will be assembling the engine and slapping the head on this thing.. Ill have more pics after that..

Along with the pics will be plenty of ?'s... Like, What clutch should I run? I know I wanna run the Z1 flywheel but do I just purchase the Hf clutch?? Then there's the infamous wiring... If anyone has prior experience and can lend a few tips on this end that would be awesome...

02ws6 · 08-31-2011, 01:25 PM

Was just looking at info and turns out that all the discs are 210mm outside diameter... Looks like Ill be purchasing one for a 90Si at the end of the week..

Gonna break out the chilton's manual later in the week after the engine is assembled and get these pinouts broken down.. Still havent decided if I want to modify the Si or Vx engine harness..

z3pilot99 · 09-27-2011, 09:07 AM

Hey I'm doing this too. Purchased the D15Z1. Doing the research on the swap.
Bunch of info out there. Here are some links...

Plugs you will need to put a d15z1 into your MPFI Civic/CRX - GasSavers.org - Helping You Save at the Pump Hypermiling and Fuel Efficiency Forum
Bunch of helpful things on rywires site.
All Articles : Rywire

I am sticking with my existing harness and making changes outlined on the first link above. I will just need to get a few connectors.

Do we have an actual idea what the end result mpg will be? Is it 60+? I am hoping that the Z1 engine along with some aero modifications like the aerocivic will get me in the 70's.

z3pilot99 · 09-27-2011, 09:13 AM

Oh, and I hope you got the EGR control box. That is a very hard part to get. I was able to get one with my Z1 engine. I don't know if I will need it since my HF engine already has a EGR valve and control box.

02ws6 · 09-27-2011, 07:36 PM

Ive got all that stuff.. Have been reassembling my engine as of late and still kinda deciding on what imma do with the wiring.. At first I thought about doing a wire tuck along with all this.. But seeing as this will be an everyday driver, Id rather just keep things as simple as possible..

I have found a website that seems as legit as rywire but way cheaper.. Thought about just buying their harness and just modding it to what Ill need.. Im still in the air as to what imma do though.. May just do the work myself..

http://www.phearable.net/shoppingcar...ness-p-35.html

Has everything you need and the distributor plugs for 154.00 plus shipping.. Still have to add the egr stuff and 5 wire 02 sensor though... prices are way better than rywire though..