20 replies to this topic

[chedda_j]

First of all, I already have the D16a1 swapped into the car. Here are some photos of the pieces side by side, I want to point out a few things.

Here is a comparison in Cams to start. Note the different Cam codes stamped on the Zc and D16a1. I also measured the height of each lobe, the d16a1 had a height of 1.240", where as the zc had a height of 1.300". Quite a bit of difference. This was on the intake profile.





Also note that the cam gears on the zc are made of aluminum and are much lighter to increase horsepower.

ZC on the left, D16a1 on the right. Both have 40 teeth.



Another thing, the D16a1 intake and Zc have different fuel rails, vac ports and a different location for the fuel hook up.

D16a1 Intake



ZC Intake



I also want to note that the zc has two throttle body butterflies, where as the D16a1 only has one, which I will likely change for better flow.

D16a1 Throttle Body



ZC Throttle Body




I have the JDM ZC ecu and as far as I know the ecu is plug and play with the d16a1 harness. I have also been told that the distributor and CAS is also interchangeable. No one has said anything about throttle bodies yet, but from what I can see they look to interchange as well.

So I was hoping someone could chime in and help make sure I can swap throttle bodies, and if its going to help or hurt horsepower.

[eec4tuner]

I read somewhere that there is better bottom end response with the dual butterfly throttle body.

[Mrfixit]

This is a first gen zc correct? My zc tb and d16a1 tb are the same. I have an extra one so I think I will take it to maxbore and have it reworked.Is this the engine you are building for the civic?

[chedda_j]

This is correct, a first gen ZC. The first gen ZC from Japan, had a dual butterfly throttle body. Its one of the was to tell if its a ZC or not. This is just the daily driver motor for my car. My built motor is a 76mm D16a1, that's already half prepped for a my .63 ar t3/t4 turbo.

Here is a little quip from Wiki. (not that you can ever trust wiki...but)

1st Gen ZC Identified by: External coil, small distributor, dual butterfly TB, cam cover bolts on top, brown/gold cam cover. Large cam pulleys. +3cc PG6B pistons, non-pent roof combustion chamber. As a ZC it appeared in JDM AV Integra Si and JDM E-AT Civic/CR-X Si. Commonly produced at the time but now over twenty years old and getting harder to find. D-series version is called D16A1, 1986-1987.

[PowerWheels86]

This is correct, a first gen ZC. The first gen ZC from Japan, had a dual butterfly throttle body. Its one of the was to tell if its a ZC or not. This is just the daily driver motor for my car. My built motor is a 76mm D16a1, that's already half prepped for a my .63 ar t3/t4 turbo.

Here is a little quip from Wiki. (not that you can ever trust wiki...but)

you talking about the regular internet wikipedia or our wiki? hahaha because ours is totally reliable!! minus the fact it hasn't been updated with the information that you can use Hasport mounts to put a 88+ d-series motor in... hahaha

[chedda_j]

Lol. No that was internets wiki. This is a jdm zc, first gen, so it will actually bolt right up to the other mounts,.

[ty89teg]

First of all, I already have the D16a1 swapped into the car. Here are some photos of the pieces side by side, I want to point out a few things.

Here is a comparison in Cams to start. Note the different Cam codes stamped on the Zc and D16a1. I also measured the height of each lobe, the d16a1 had a height of 1.240", where as the zc had a height of 1.300". Quite a bit of difference. This was on the intake profile.





Also note that the cam gears on the zc are made of aluminum and are much lighter to increase horsepower.

ZC on the left, D16a1 on the right. Both have 40 teeth.

From what I've researched the ZC Cams timing marks are aligned different too compared to the A1, wondering if you could verify that. Also, if anybody knows if a F22A/B cam gear fits/works on the D16a1. Funny to see the ZC using the cast aluminum gear like the original EW1 instead of stamped steel

[chedda_j]

I think its pretty obvious why they would use a lighter aluminum machined gear rather than a stamped gear. The ZC was the epitome of Japanese Honda performance motors in that era, there was a reason for everything they did.

The F22 gear set will work on the ZC so I don't know why it wouldn't work on the D16a1. One thing I can remember is that if you want to use the ZC cams in the D16a1, you had to retard the one gear, the intake gear if I remember correctly.

Also what I want to note is that there is no real good reason to use the adjustable gears unless you have high comp pistons, cams, and or tunable ignition. Most people run -1 degree on the exhaust, and +1 on the intake if I remember correctly.

[chedda_j]

Some more good info right here:

The throttle bodies are in no way interchangeable between the ZC and D16a1.

You can see in the photo below the bolt patterns are different. Earlier I said that I was going to change throttle bodies because the D16a1 has a larger butterfly. After doing a little bit of research, you can see that the actual inlet on the ZC is massive compared to the D16a1. So in lack of butteryfly diameter, it makes up in a very large bore. With that, I can see why they designed it with the two butterflys rather than one, to create more torque in the bottom end. What another cool find.



OH and the sensor on he back of the intake, the TPS is interchangeable, but you have to grind the rivets off the shitty D16a1 TPS to remove it, where as the ZC is serviceable and removable with a 9mm socket or Phillips screwdriver.

[eec4tuner]

Some more good info right here:

The throttle bodies are in no way interchangeable between the ZC and D16a1.

You can see in the photo below the bolt patterns are different. Earlier I said that I was going to change throttle bodies because the D16a1 has a larger butterfly. After doing a little bit of research, you can see that the actual inlet on the ZC is massive compared to the D16a1. So in lack of butteryfly diameter, it makes up in a very large bore. With that, I can see why they designed it with the two butterflys rather than one, to create more torque in the bottom end. What another cool find.



OH and the sensor on he back of the intake, the TPS is interchangeable, but you have to grind the rivets off the shitty D16a1 TPS to remove it, where as the ZC is serviceable and removable with a 9mm socket or Phillips screwdriver.

Slot the rivet with a dremel grinder with a cut-off wheel disc or use a hacksaw blade and it's easily removed with a flattip screw driver.

[BlackRose]

I haven't checked the lobe heights but.... I have 2 sets of D16A1 cams; (1 from a brown top & the other a black top) they are stamped RA/RB and R1/R2. I can't remember which set is which.  The intake that was on the motor is marked PG6X. The pistons are PM7s.

 

I also have a set of JDM cams (stamped PM7) and the intake marked PM7 as well. These came from a 3rd gen ZC.

 

I can't remember whether the block is an 86/87 or 88/89. I have 2 questions.

 

First, is there a difference between the 86/87 (short) block and the 88/89? I saw engine kits (from Clegg) and they have 2 different ones.

 

Second, and more importantly, if  I build the engine with PM7 cams, intake, and pistons (if I don't bore & change to P29s) will I have a ZC? I know i's not a ZC block, but for all intent it would be a ZC. Right?

[PuddleSkipper]

First, is there a difference between the 86/87 (short) block and the 88/89? I saw engine kits (from Clegg) and they have 2 different ones.

 

I think the main differences are the oil pump and the pistons.

 

 

Second, and more importantly, if  I build the engine with PM7 cams, intake, and pistons (if I don't bore & change to P29s) will I have a ZC? I know i's not a ZC block, but for all intent it would be a ZC. Right?

If your trying to get to the 130 hp mark, yes, for all purposes, internally it would be a ZC. Are you Browntop or Blacktop? If your Browntop you'd need the JDM computer as well, if your Blacktop you can swap in a 90-91 PM6 or the 90-93 Integra ECU board into the PG7 case and chip it with a PM7 chip from ebay. If your going to run the PM7 cams you'll probably need the cam gears and crank gear as well

 

edit: forgot to add the 4-2-1 factory "header" was also part of the package, like what the B series has and the D16Z6 has. The D16Z6 would probabably work but you'll need to port the exhaust a little to match it up and I think the primaries might be a little bit smaller. I'll find out when I start restoring mine.

 

http://www.thezcr.co...ead.php?t=20521

[anjin]

There are gearbox bolt up differences between the browntop (PG6) and blacktop (PM7) blocks.

[BlackRose]

Any idea what year my block is? It had PM7 pistons in it. Wiki (internet) says D16A1 `86/`87 has PG6Bs, `88/`89 has P29s and `88/`89 ZC has PM7s. The block is marked D16A1.

 

As far as the gears go, I have brown & black top gears (stamped steel & cast Aluminum). I also have the (smaller) 3g JDM ones. I think I can use the (larger) cast Alum. (USDM) ones with the USDM crank gear. I have both the brown & black USDM heads as well.

 

I'm thinking black top head, 3g JDM PM7 intake, D16 4-2-1 header, JDM cams, USDM cast cam gears, and PM7 or P29 pistons. Then I'll have to see about the ECU.

[BlackRose]

So, it sounds like I have an `88/`89 block. Since the pistons are PM7s. Is that right? I need to know in order to get a rebuild kit & tranny. Is there any other way of determining what year the block is?