L8apex

Not in FAQs and search function no worky.

Rebuilding my USDM B16A2/S4C trans and was going to drop in an ITR helical LSD. Want to keep stock ring gear.

All set to buy one and now I hear that not all will fit in the transmission housing without modification. And that not all ring gears are compatible between USDM and JDM models.

Can anyone shed some light on this? The ideal situation would be no modifcations to the trans housing and reuse the stock ring gear. Which one fits the bill? Thanks in advance.

madm@nkey

Get the LSD, ring gear and final drive for the USDM ITR.
The gearing is the same, 4.40.
You have to buy the new ring gear, bolt pattern on the LSD is different.

L8apex

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by madm@nkey &raquo;</TD></TR><TR><TD CLASS="quote">Get the LSD, ring gear and final drive for the USDM ITR.</TD></TR></TABLE>

What do you mean the "final drive"? The final drive consists of the ring gear (on the differential) and the pinion (on the countershaft). Are you saying I need to get the ITR countershaft/pinion to mesh with the ITR ring gear? The ITR ring gear should mesh with my stock B16A 4.40 contershaft/pinion.

Good info on the bolt pattern. Did not know that.

Cory Matthews

hey was there ever an oem lsd for a d series? if not what are my options?

madm@nkey

Forgive me for the mistake, it was too damned early and I was barely awake.

But to answer your questions:

Yes, you need to buy both the ring gear and the countershaft for the USDM ITR.
You would think that the stock countershaft should work with the ITR ring gear, but it does not.
There are differences between the parts, the width of the ring gear on the ITR is not the same as the Si.
The cheapest way to go is aftermarket, then you can keep the stock countershaft and ring gear.
If you must go OEM, you have to buy the LSD, ring gear, countershaft and 10 bolts for the ring gear and LSD, shims to make it fit, and, depending on the mileage, new bearings.
Hope this helps

L8apex

That helps a whole lot! So it's the price of an aftermarket LSD vs. OEM LSD, ring, pinion/countershaft, bolts. At which point, one should consider going with a more favourable overall final drive ratio. But that's a topic for another post. https://honda-tech.com/zerothread?id=1413557 And I'm not going that route. Bet you know what the next question's gonna be...

What aftermarket LSD would you recommend that works as seamlessly as the OEM torque biasing one? I've heard that the friction disc types tend to clunk when cold. And so does the Quaife ATB. But then again, all hearsay. Experience with any setups anyone?

L8apex

OK, more research. From what I can decipher in Japanese publications, JDM EG6, EK4, and EG2 use the same LSD, and the EK9 and DC2 use a different one.

I can only assume that the B16A cars eqiupped with LSD share the same transmission internals and thus have compatible OEM LSD's. Anyone confirm or deny this? Last resort is to go LSD shopping with ring gear in hand. Kinda hard to do online though.

black_EM1

The EK9(CTR) transmission is the same as the transmission in the Si, but with a limited slip and dual synchros on some gears, I believe. Gear ratios and FD are the same