ZC swap info

ZC Identification Guide​


The ZC engine is one of the hardest to identify because there are many different versions of this engine. Honda offered this engine in both single and dual overhead cam designs, as well as fuel injected and carbureted versions of these. This article distinguishes the different versions of the ZCs offered. Hopefully this will separate the facts from the myths.

The First Generation ZC​


ZC's were first offered in Civics and Integras in 1985 and were still being manufactured in vehicles up until 2001. The first Generation ZC's were offered from 1985 through 1987. These engines can be found in 85-87 JDM Civics and JDM CRX Si's and were very similar to the 1986-1987 US Integra engine. It's worth noting that this engine came with the highest horsepower rating of all ZCs at 137 horsepower. Remember, these engines were offered in Japan and similar versions offered in the United States were only offering 112 horsepower. The main difference is Japan's higher quality gasoline and different fuel curves along with slightly higher compression. These engines are usually bolted into 1st generation Crxs and 3rd Generation Civics along with 1986-1987 Integra's. Most of this is pretty straight forward. The main problem lies within the carbureted versus fuel injected models offered during these years. This conversion is both difficult and time consuming and really not recommended because the results really aren't that impressive.

Swapping the 1st gen ZC​


To bolt this engine in, the following mounts will be needed. First, the passenger side mount and rear mount from the ZC/Integra should be used while the driver's side mount and bracket need to be used from the Civic/Crx. To make things easier with wiring just use the stock wiring harness. Several of the wires may need to be lengthened but there shouldn't be any other problems. Ideally, the ZC ECU should be used however the Si ECU is adequate. If installing the Civic ZC into an 1986-1987 Integra is the goal, you'll need the Integra intake manifold and throttle body. Remember, the OEM wiring harnesses should be used with its own engine to make the swap easier and cleaner.

The 2nd Generation ZC​


In 1988 Honda introduced the second generation of ZC's. These came with a black valve cover and have several differences when compared to the first generation ZC's there. First, its important to realize that there are two types of ZC's. The first, offered exclusively in JDM Civic's/CRX's, has ZC stamped on the block. The second is the D16A8/D16A9 and it came in USDM Acura Integra's. These two engines are not interchangeable with one another and have different engine mounts. The Integra's driver's side mount is located near the front of the engine while the JDM ZC's engine mount is closer to the timing belt cover. It is also worth noting that the valve covers and intake manifolds are also slightly different.


What do these fit?​


Because the 88-89 Integra ZC engine mounts the same as the 86-89 Integra, the engine will not only bolt in to the 88-89 Integra, but also into the 86-87 Integra and 84-87 Civic or CRX. Cool you say? Well, sort of. The reason this is not done more often is because of the wiring differences. Some big changes need to be done. The two major sticking points are vehicle speed sensor and electronic load detector. These require more than just a couple of wires for the conversion to work. The 88-91 Civic style ZC is a direct bolt in to the 88-91 Civics and CRXs. You can bolt the ZC to the stock transmission easily too. You just need to make sure you have the right clutch and flywheel combo. The easy way is to match the pair to what ever year tranny you use. Electrically the ZC is identical to the Si with the exception of the distributor wiring.

If you decide to use the Civic ZC tranny with your Civic ZC engine, get the Civic ZC intermediate shaft because there is no US counterpart to this part. The 86-89 Integra intermediate shaft will not fit, and I don't care what your friend heard or said.



The 3rd Generation ZCs​


Is there such a thing?

After 1992 in some Civics and a few 1994 and up Integra's still come with the odd model: the DOHC ZC. These ZCs look like the Civic style ZCs from 88-91 but have the later style electronics. There are even more Integra and Domani models with SOHC ZC engines. There is not a lot of interest in these (SOHC or DOHC) engines I am afraid, because the B-series VTEC motors bolt right in the 92 up Civics. The ZC does make a good swap in the lowly, underpowered CX or VX, but only with the EX, Si or ZC transmission, otherwise I don't recommend them. But for the sake of argument and to impress you with our large volume of trivial Honda knowledge, let's go ahead discuss them.

To recognize the 3rd generation DOHC ZC engine, just look for the black valve cover and 92 up grey colored electrical connectors. Some of the other visual clues are:

  • a plug in the end of the exhaust cam, like the B-series motors
  • two studs sticking up from the driver's side engine bracket poking out of the timing belt cover
  • and no writing on the top of the intake manifold, just the three raised bars on the casting like all the other 92-95 Civic engines.

What do they fit?​


Well, they will fit the 92-2000 Civics or the 94 up Integra... not that anyone would want to put it in an Integra. Again, this engine bolts to the stock transmission and the Si or EX trannys make for a decent combo. But if you decide to use the 92 up ZC tranny with your 92 up ZC engine, get the 92 up Civic ZC intermediate shaft too because again, there is no US counterpart to this part. Although it is different from the 88-91 style, it is interchangeable.


Hopefully this clears up some debate about the ZC motors. As always, feel free to check out our forums for any questions you may have.
 

posol

RETIRED
Staff member
Message Forwarded From buymysoul

Hi, I was looking through your ZC swap writeup from January and noticed a few mistakes.

The "blacktop" ZC that was in the 88ish Integras actually has ZC stamped on the block. It is easily distinguishable from the CRX ZC of the same years because the valve cover bolts are closer in towards the spark plug wires like a USDM 86-89 Integra motor (which I also noticed you made some typo there about it being a D16A8 or D16A9, the USDM one used the engine code D16A1 for those years (even though there were pretty big changes between 87 and 88).
The D16A8 and D16A9 were used in CRXs in other countries (I think the helms I have is from England, but don't quote me on it)

If you don't believe me, look around www.g1teg.org there are a few guys on there who have blacktop integra ZCs in their cars and they are actually stamped ZC. Also, the euro CRX helms I have is available at different places online. And I'm sure you can look on ebay to confirm that the 86-89 Integra engines were stamped D16A1


thanks for the Update dude =)
 

posol

RETIRED
Staff member
More info:

THUD said:
Hi there well I have a few things to add to a write up on ZC's that you have- link https://hondaswap.com/swap-articles/zc-swap-info-29123/
I just want to add to it since it was the only dam thing on the net that really helped me on my swap, it was the only artical to described the differnces well between ZC's.
If you could post this up in there with all that or just tell me were I should post this and I will doit but thanx's for the info dude keep it up!! :D


3 gen ZC for my 93 civic DX part numbers and tips
NGK premium platinum tip/G-Power spark plugs part# BKR6E-GP stock ones are with out the GP, DENSO
#K20PR-L11 as per the sticker on my timeing cover.
I am not sure what other honda motors have them but it's very common plug to find.
NGK plug wires #RC-HE48 there for a 89 acura integra ZC and the set comes with a coil wire...nice
lil Xtra
YEC dizzy cap#141-4185
YEC rotor 141-3168
Timing belt #14400-pk2-044 and that's straight from Honda.
It's a perfect OEM match and all the stuff say's it was made in Japan!..I also looked over the
parts and the quality is good and is better than Neineoff or how ever it's spelt.
The D15B7 and Si and this ZC all have the same cap but the bolt pattern from the head to the
distributor housing is differnt due to the cam sensor being inside the housing on the 3gen ZC.

THE SWAP PROBLEMS
My JDM motor came with about 42,000km and the only things that I could complain about was the
fact it was choped out of the car it came from, wiring harrness,hoses.
The MAP sensor was busted off the top of the throttle body on the ZC but the D15B7's MAP sensor
is located on the fire wall so I just swapped throttle body's due to the slight vacum routing
differnces between the 2 motor's....not hard there's one extra line that needs vacum so I T'd a
line for it.
The power steering pump rubber hose for the d15b7 is about 1 inch shorter and the metal line part
bends a bit into the mount that hooks up to the orgianl pump from my car, so I had to do just a
little bit of grinding on the mount as it is not wise to bend that line and the hose is kinda
snug and does not fit back in the the little clip located on the underside of the intake
manifold.
Now what really stumped me for a good hour was......injectors/fuel rail was clogged or rusted
shut cause when I cracked the fuel line on the end of the rail it sprayed every were like it was
over pressured.
Swaping all that with the old d15 stuff did the trick, so far it's running great and the tranny
is the same as what was in the car so it was easy swap that took about 7 hours for me and a buddy
to do.
This Was an easy upgrade and other than slightly better fuel economy in the d15 this ZC kicks
it's ass hands down!!!
 
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