So I happened to blow my first motor in my 90 CRX Si. It's also my first project car and I am also teaching myself on it so I'm still learning a lot. I just did my head gasket with a bit of help from a friend that works on Hondas a lot. He suggested I should post here.

I'm looking to swap a D16ZC motor in place of the D16A6 as I've heard it's a good motor with little to no complications to swap into a crx. have a couple questions like what mounts do I use? Will I be able to use the a6 transmission? Exhaust? Intake? Would the hondata s300 ecu be a good option?

Any answers or advice would be much appreciated and thank you in advance!

 

I also would like a little more power than an a6, but looking to keep it reliable.

 

Paging jlicrx....


DOHC ZC was a popular swap in the late 90s and 00s when 10-15 year old engines were being imported from japan and other countries. They were relatively cheap.

Nowadays? I doubt you could find a decent DOHC ZC. That well has dried. I dunno, just my feeling.

They do make for an easy swaps, which also made it popular. They fit in usdm trannies. Wiring should be plug n play. Even a stock ecu works. It's the easiest swap possible really.

I think you'll find a later D series (including a SOHC ZC, there's many versions) in better condition easier than a DOHC for cheaper.

I'm sure jlicrx has more to say.

 

Do you already have the ZC engine?

 

I don't yet, I ended up finding a k20a3 motor yesterday for $250 that I'm thinking of swapping in. I've heard its a lot more work than swapping another d series in, but my original plan was to swap a K series into it, just not as soon. The guy I am buying the motor from is holding it for me until I can pick it up. Would it be smart to do a k swap as I'm still learning to work on cars? Or is that a little too advanced for a beginner?

If I go the D series route, I was thinking ZC but as stated in a reply above, they're hard to find in good condition nowadays. Suggestions for a d series motor if I should go that way? Or full send the k swap. I know I would at least need some hasport mounts, '06 RSX type S transmission, shift linkage, ecu, harness, etc.

I'm on a tight budget and buying parts as the money comes across to me, but I want to make sure I do it right and proper the first time. So spending a little extra for quality and/or parts to do it right isn't an issue.

I know I eventually want to slap a turbski on there but once I have more knowhow and when I know for sure the motor can handle it.

 

well that escalated quickly...

yeah its a completely different swap. EVERYTHING needs to get updated, including shifter, gauges, wiring... all that adds up. i dunno what the current estimate is but $6-$10k for a K swap seems about right. dont take my estimate tho.

 

Is it something a beginner should attempt to do? I don't want to get like halfway through and run into so many problems that I lose interest. Not that that's likely to happen to me though.

Would it be wise to stick to a d series swap to learn more before I decide to take on something bigger?

As you were saying in a past reply about the SOHC ZC, if I go with that, would it be possible to find one at a junkyard and rebuild it?

 

Undoubtedly, you should do a successful engine R&R on a D-series before doing a full on swap. the SOHC ZC would be bought from an importer most likely, since it's the Japanese engine. The single cam ZC is a direct bolt in procedure, everything should go in smooth, and pretty much anything from the D16a6 will drop right in.

 

I know I need to at least find a block for the d16a6 that is compatable with the A6 head or a y7 head that I have. The block that I currently have has 2 holes in the rear side of it from throwing a rod I'm assuming. So I need to at least do the whole bottom end of the motor.

 

A K swap is much more involved for sure, but the parts and knowledge is out there to make it easier. It's going to depend on your budget, resources (time, tools, helping hands) and patience for projects.

What happened to your D16A6? Unless you blew a hole in the block it might be worth keeping. I kinda miss mine, they are great engines and simple to work on. I learned a ton about Honda engines by playing around with it. Mine ran strong with 280K on it. Re-ringed the pistons to keep it from eating oil, it even snapped a timing belt and didn't kill the valves.

 

I ended up blowing it, and there are 2 holes in the side of the block toward the firewall by the alternator. I don't think it can be saved unfortunately. Would I be able to just find another d16 block and use that?

I'm thinking swapping another d series or getting another block would be ideal for my situation. Rebuild it before throwing it in and all should be well hopefully. But I guess you never know with cars, and since I'm still learning about working on cars, this is kinda frightening to have to tackle but I'm dedicated and have the will to do it. I love that car and am willing to do what it takes to get my end goal with that car.
I am also looking to challenge myself just a bit, since that'll make it fun

*SIDENOTE* The chassis odo is only at 137,050. Makes me wonder if the previous owner pulled a junkyard motor of some sort and threw it in, that was higher miles than the chassis. Seems reasonable to me. I also have never pulled this engine out to REALLY look at it.

 

that block is toast. the head may be salvageable, depends on if the valves were impacted (sometimes you get lucky), and no other damage in the combustion chamber.

if youre being apprehensive about this being your first major engine work, just find a SOHC ZC or USDM model replacement. swap it in completely including the head. if you REALLY want you can completely rebuild the new engine before putting it in, but thats a lot of work for little gain, unless you just want to do it for fun and experience. if its from an importer, i would consider it good and not worth it.

you cant really find the DOHC ZC anymore unless you get lucky or know exactly where one is available. like i said, that well has dried over a decade ago.

also, the thing about finding imported SOHC ZC, many were previously carbureted, which will have a mechanical oil pump port opened on the back of the head on the distributor side. you just need to block that off. you MAY want to swap in the old A6 cam, as the carbureted cam is slightly off in timing and lift. but its not required. if there is no open port, then it should be good to go. there are ALSO VTEC SOHC ZC, that are like Z6 and Y8's. that should be obvious with a different valvecover and VTEC solenoid ports.

i go more into detail about SOHC ZC here. https://honda-tech.com/forums/honda-...eries-3186610/

 

I have a 91 civic hatchback Si. I was looking at different engine choices myself, d16z6, B series or k series. For me air conditioning is important so I’ll likely go for either the simple D16z6 which is vtec or b series vtec

 

What does the z6 or y8 come in? How hard are they to come by? Are they plug and play with the a6 wiring harness or do I need another one and an ecu? I was told to get the Hondata S300 ECU and convert to OBD1. Good idea?

 

for the z6 you’ll need a P28 ecu, but other than that I think it’s plug and play. I hope someone else could confirm this

 

i agree that the DOHC ZC was a relatively easy swap in it's day and they are now getting harder to find, especially the OBD0 version. I've seen a few places that have the 92-95 OBD1 version of the DOHC ZC. None of them are cheap any longer. 20-25 years ago we were paying around $700 for the ZC engine, the ZC transmission and PM7 ECU (engine alone $450-500) - you would be lucky to get just the engine these days for somewhere between $1300-1500.

found this: ebay.com/itm/164614541209?epid=2097622848&hash=item2653ca8f99:g :cPsAAOSwVi9f669z

That said, I see a lot of posts regarding swaps in the 88-91 cars saying get a D16Z6. Keep in mind that the D16Z6 was also 92-95 which makes them 25+ years old and finding a good one is not easy, as most are used up and in need of a rebuild.

 

to use the Z6 the wiring is not plug and play - you would need to use the P28 ECU, use the OBD0 engine wiring harness and convert it to OBD1 with ECU jumper, distributor jumper, 4-wire O2 sensor and changing some other wiring like the cooling fan switch.

 

I do know that if I am wanting this engine swap to be done right and thorough, I would want to at least tear apart the engine and rebuild it if it's needed. The most intensive thing I've done on an engine so far is a head gasket with the help of a friend walking and helping me through the process.

So I guess my decision is to try and find a z6 motor and work with that. I've heard they come in the 92-95 Civic EF and SI? Are there any reputable places that are online or in the US that would be a good option to look into for finding one of these bad boys?

 

$1299 dafuq... lollooll


i guess in fairness, shopping around, like jlicrx said, there really isnt any quantities of 25 year old engines. and i guess its hard to expect them to go for $400 like the did 20 years ago...

 

Hmmmm I just found a DOHC ZC for about $2,000.

 

Equinox19, if you want, I currently have two ZC engines. One a SOHC and the other a DOHC from a first gen Integra. I can tell you this, there isn't too much of a difference in the swaps. However, with that being said, the compression ratio's are almost identical, thus the thirst for HP or Torque will be about the same from a numbers stand point. (DOHC will get you more steady Torque in the lower to Mid ranges, but that is about it). As far as trans go.. I haven't tried to pair one yet, but I have an extra trans lying around so I can try to match up the mounting bolts.

 

the 1st gen Integra D16A1 block will not bolt directly to the 88 and up D-series transmissions - one of the bolts, which is the bottom bolt on the rear of the engine doesn't line up - you can make it work by enlarging the hole in the block and using a larger flat washer - another problem is with the starter bolts - on the 88 and up, one starter bolt runs through the transmission and attaches to the back of the block - the D16A1 has no hole in the block for this bolt - the biggest problem is the driver's side engine mount - on the D16A1, the mount is on the front side of the engine, not on the end like SOHC D-series mounts - the only way around it is to fabricate a mount for it - here is picture of the D16A1 - the mount is on the left side in the picture

other problems could arise depending on the year of the D16A1 - 86-87 had an vacuum advance ignition system which is not compatible with the 88-91 Civic/CRX and had a horrible intake manifold - the 88-89 D16A1 did have the electronic advance ignition and a better manifold - there are other things that make the 86-87 undesirable

 

So I've managed to find a D16Z6 motor for $500 with 90xxx miles and paperwork.

Reading back through the replies I'm assuming it's plug and play? It appears to be SOHC ZC.. or that's what it's saying in the ad..

 

Make sure to get the correct ECU.

 

Which ECU do I need? There's a couple floating around Facebook marketplace...