johnnysixer

iTrader: (1)

Ok I'm a little confused. Where is the transfer case located? Is it near the front differential, near the rear differential, is it a differential itself or what?
I know this sounds (and most likely is) a noob question, but I'm totally drawing a blank here.

I apologize if this has been covered already, and yes I did use the search button...without much luck though. So if anyone can fill me in, or has any links or whatnot to educate me about this I would greatly appreciate it.

marksae

iTrader: (12)

The transfer case is mounted to the transmission behind the engine. I circled it in red below.

lil'evil_evo

iTrader: (17)

Can't do any better than that.

jcnel_evo8

iTrader: (2)

Thx ... dude ... nice pice ... however my ever curious mechanical mind really is trying to figure all this out ...

The Center Diff is in the tranny ... it manages the 'torque' difference from the front and back wheels. So ... with that said ...

The left half shaft goes into the 'tranny' and the right, into the right of the 'transfer-case' assy.?

How does the center diff seperate itself from the front diff that resides in the x-fer case?

Does the center diff. 'spline' onto the transfer case, and the left half-shaft go 'through' that into the front diff?

Does the transfer assy. fit 'outside' the front diff ... so that it does nothing more than transfer the power to the rear driveshaft? Does the front diff. ride inside the assy. on like a set of bearings?

Ever Curious,

jcnel.

johnnysixer

iTrader: (1)

Thanks for the illustration. Now my next question.

I plan on starting to mod my car pretty soon, and an upgraded clutch(not sure exactly on which one yet) is high on my list. From what I have read on this forum, Mitsubishi made the clutch weak on purpose, in order to save the transfer case. Now if I upgrade the clutch, won't that put more stress on the transfer case? If so how can I strengthen the transfer case to better handle the higher stress?

Also, somewhat related, I have read that Turbotrix put an LSD in their transfer case(according to Turbo magazine). Whats does this do?

marksae

iTrader: (12)

While I've never taken apart an EVO tranny and transfer case, I've looked through the shop manual and have a good idea of how it works.

The center diff drives the transfer case w/ a hollow output shaft. This output shaft drives the front diff housing and viscous coupling (inside transfer case). The driver's side axle goes through the center diff completely and into the front diff. The VC is what modulates how much power gets transmitted between the front and rear wheels.

I probably just confused you some more. For your reference, look at page 22A-3 in the shop manual. There's a sectional view of the tranny and t-case that shows how the front and center diffs work w/ each other. I can't capture the detail of that page w/ a screen capture on my computer since I'm not running a high enough resolution.

marksae

iTrader: (12)

The weak link in the EVO drivetrain is the front diff inside our transfer case. What destroys them is wheel hop during hard launches. Wheel hop sends shockloads through the spider gears inside the diff and they break. Quaife is coming out w/ an upgrade front diff for our cars. This should fix this issue.

The #1 cause of these failures is launch technique. People need to realize that AWD drivelines cannot take redline clutch drops! The best way to launch an AWD car is to slip the clutch from around 5k rpm. You need to know to let off the gas if your front wheels start hopping off the starting line.

One of the reasons why people think our stock clutches are real weak is because of the clutch restrictor. The restictor slows down clutch disengagement and causes more wear on the clutch to help save the driveline for the novice drivers who don't know how to launch an AWD car. Our stock clutches are stronger than most people give them credit for. They can hold 350+whp, which is pretty damn good for a stock clutch in my book.

johnnysixer

iTrader: (1)

So if I do upgrade my clutch, and don't do any redline clutch drops my transfer case should be alright?

marksae

iTrader: (12)

Yeah, never do any clutch drops with any clutch and your transfer case should last. Also, if you ever get wheel hop when launching, let off immediately.

johnnysixer

iTrader: (1)

Thanks alot for the help.