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.
![Posted Image](http://i3.photobucket.com/albums/y64/cheddaj/D16vsZCcams.jpg)
![Posted Image](http://i3.photobucket.com/albums/y64/cheddaj/D16vsZCcams2.jpg)
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.
![Posted Image](http://i3.photobucket.com/albums/y64/cheddaj/IMAG1202.jpg)
Another thing, the D16a1 intake and Zc have different fuel rails, vac ports and a different location for the fuel hook up.
D16a1 Intake
![Posted Image](http://i3.photobucket.com/albums/y64/cheddaj/d16a1Intake.jpg)
ZC Intake
![Posted Image](http://i3.photobucket.com/albums/y64/cheddaj/zcIntake.jpg)
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
![Posted Image](http://i3.photobucket.com/albums/y64/cheddaj/D16A1ThrottleBody.jpg)
ZC Throttle Body
![Posted Image](http://i3.photobucket.com/albums/y64/cheddaj/ZCThrottleBody.jpg)
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.