I guess I should start out by stating what my goal is and why I decided to go with this transmission combo. This is going in my 4th gen hatch with a D16A6. I was looking to achieve faster acceleration in the 1-4 gears while retaining the SI 5th for gas milage.

So I obtained a cable L3 ZC transmission from a friend of mine. I identified this transmission by bigger axles...that is the correct way right?

Everything is pulled apart now. I used the Si case (are both cases the same?) and had it cleaned and gave it a fresh coat of paint. I ordered an Si transmission rebuild kit from the ebay guy and was pleased to find out that the bearings are all NTN with the exception of the diff bearings, which are Nachi.....so these bearings are OEM equivalent. The price for the rebuild kit was $177 shipped with syncros. The syncros are not the exact quality of the OEM ones, but they are close...so I will inspect the OEM's and replace only if needed.

I pressed in all the new bearings and now have the SI main and countershaft pulled apart. The ZC main and countershaft have been pulled from the case, but I left them together for reference.

Here is where I am confused....

I need to know which gears are which...as in...how do I identify the ZC 1-4 that will be swapped to the Si final drive. Also, where is the 5th gear SI gear located?

Does anyone know of a ZC hybrid trans "how-to" with pictures for reference?

I am going to have a few more question....so stay tuned.

Thanks very much for your help!

Case with new bearings pressed in







ZC mainshaft


ZC countershaft


I color coded everthing so if anyone knows what I need to swap they can easily explain it, as in "swap the blue to the SI shaft."

 

your red marking is 5th...... one problem though. using a si final requires you to use the si 1-2 as its part of the mainshaft and 2nd gear between the si and dohc zc is not interchangable. i went by mista bone's info and ended up using the zc 3-5 on the si main and countershaft alsong with the si final. second gear in your photo is yellow..... if you notice on the mainshaft this gear is part of it...... and only can be interchanged on the countershaft. there fore no ability to use the zc 1-4 and the si final.

 

you need the si countershaft and ring gear to swap the final drive

- swap the ring gear on the diff for the si
- take all the zc gears off the zc countershaft and transfer them to the si one
- swap the top gear on both shafts for the si fifth (red one in your last pic)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iain &raquo;</TD></TR><TR><TD CLASS="quote">you need the si countershaft and ring gear to swap the final drive

- swap the ring gear on the diff for the si
- take all the zc gears off the zc countershaft and transfer them to the si one
- swap the top gear on both shafts for the si fifth (red one in your last pic) </TD></TR></TABLE>

I am using the SI diff with the SI final drive.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by finalimpact &raquo;</TD></TR><TR><TD CLASS="quote">your red marking is 5th </TD></TR></TABLE>

Ok, Cool. So in the Helms it shows that as 5th, but it also shows a 5th on the mainshaft also...so do I need to swap both 5th gears?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by finalimpact &raquo;</TD></TR><TR><TD CLASS="quote">one problem though. using a si final requires you to use the si 1-2 as its part of the mainshaft and 2nd gear between the si and dohc zc is not interchangable.</TD></TR></TABLE>

I believe this trans is from a single cam ZC, as it shows an "L3" on the case.

Edit: Tyson just let me know that it is a DOHC ZC and the SOHC ZC is exactly the same as the USDM Si box.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by finalimpact &raquo;</TD></TR><TR><TD CLASS="quote">i went by mista bone's info and ended up using the zc 3-5 on the si main and countershaft alsong with the si final. second gear in your photo is yellow..... if you notice on the mainshaft this gear is part of it...... and only can be interchanged on the countershaft. there fore no ability to use the zc 1-4 and the si final. </TD></TR></TABLE>

I am pretty sure you can use the ZC 1-4, SI 5th and the SI final. We may be confused on which ZC trans the parts are out of...DOHC vs SOHC.


Modified by jisu009 at 12:44 AM 9/21/2005


Modified by jisu009 at 12:50 AM 9/21/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iain &raquo;</TD></TR><TR><TD CLASS="quote">you need the si countershaft and ring gear to swap the final drive

- swap the ring gear on the diff for the si
- take all the zc gears off the zc countershaft and transfer them to the si one</TD></TR></TABLE>

I have the SI countershaft and ring gear...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iain &raquo;</TD></TR><TR><TD CLASS="quote">- swap the top gear on both shafts for the si fifth (red one in your last pic) </TD></TR></TABLE>

Meaning swap the top gear on the counter and main shaft?


Modified by jisu009 at 1:32 AM 9/21/2005


Modified by jisu009 at 1:32 AM 9/21/2005


Modified by jisu009 at 1:32 AM 9/21/2005

 

Ok...I feel like a bonehead posting this. But if someone can just concur with me on this, I will feel much better.

The Helms is somewhat confusing in their diagram of the transmission. Are the blue arrows I dunn drawn correct?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jisu009 &raquo;</TD></TR><TR><TD CLASS="quote">


Meaning swap the top gear on the counter and main shaft?


Modified by jisu009 at 1:32 AM 9/21/2005</TD></TR></TABLE>
yep

iirc the si diff is different, so if you're using the halfshaft, and why wouldn't you, you need the zc diff

 

man.. that looks like my worst nightmare.. good luck

 

wait its a sohc zc tranny.......if im not mistaken the gearing is the same as the a6.....wheres mista bone to confirm when you needs him

 

he has the bigger axle opening diff and the casing had the gold L3 serial number. its a DOHC ZC tranny.

 

werd...... good luck with the conversion..... you will love it as i did.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iain &raquo;</TD></TR><TR><TD CLASS="quote">
yep

iirc the si diff is different, so if you're using the halfshaft, and why wouldn't you, you need the zc diff
</TD></TR></TABLE>

You are talking axles and diffs....

I am talking Diff's and mainshafts...

 

i know what i'm talking about

to make it a bit more clear

1) you need to use the si countershaft and install the zc gearset
2) obviously you need to change the fifth gearset on both counter and mainshafts to use the si fifth
3) if you want to use the zc halfshaft, you need to use the zc diff and not the si diff, but with the si ring gear