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DUEL T-CASES OR NOT

Posted: Sun Oct 12, 2003 9:24 pm
by mud4b
can anyone tell me the benifits of having duel t-cases or is it better to just go the series 3 rockhopper?im not worried about the cost or time.

Posted: Sun Oct 12, 2003 9:38 pm
by camskizook
u would need to seriously move your rear diff back otherwise your tailshaft would be on a frightful angle.....surely the series 3 is low enuf! :lol:

Posted: Sun Oct 12, 2003 9:52 pm
by mud4b
yeah i understand all that,the diff will be moved its a lwb also.i really need to know what you can do with duel cases not just the reduction.

Posted: Mon Oct 13, 2003 12:24 pm
by greg
mud4b wrote:yeah i understand all that,the diff will be moved its a lwb also.i really need to know what you can do with duel cases not just the reduction.


Assuming you are using 1.3L transfer cases, the twin x-fers will equate to a low gear of (2.268 x 2.268) = 5.143, so running a 6.1 transfer case would still be lower - unless you upgrade to a series 1 or 3 rockhopper in one of both cases - in which case, obviously you could set your sierra up to be stupidly low - (3.somthing x 6.1 x 6.1 x 3.something) = 334 minimum - that would be very low :cool:

Note: put in 5.12's in the diffs and we are talking 500's :cool: :D

If you question is actually, where do you put the second case, then the answer is that you need to put it far enough behind the first case to allow you to run a decent jackshaft - the shorter the jack shaft, the more issues you will have with angles and destroying bearings and unis in the x-fer cases.

If you are putting in a vitara engine also - then the norm seems to be to use the engine, gearbox and x-fercase (not divorced from the gearbox), and then the sierra case too... that equates to a much shorter total length as their is no jackshaft between the vitara gbox and xfer...

So why would you pick twin x-fers over a rockhopper -
1. for the ability to upgrade to super low gears should you choose to do so.
2. for the perceived lower starting cost (i.e. no rockhopper purchase) - which may equate to far more wear and tear and eventually a higher cost. But once you get custom drive shafts made up and spend all the time fabricating new chassis mounts for the 2nd case - it may be more expensive.
3. so that you can run lots of different gears - i.e. you have a lot of range to play with. This is something that i don't have when running a series 3 and often i find that 5th low is too slow for driving in between tracks so i change into 2 high for in-between tracks driving... but you get used to that.

i hope that answers some of what you were after.

cheers

Posted: Mon Oct 13, 2003 10:02 pm
by Beastmavster
I'm more looking at dual t/cases in an attempt to get a decent high ratio than low ratio - as the rockhopper doesn't impact the high ratio on the Vitara box.


I can't see any real need to go dual tcase on a sierra, unless you did a Vitara motor and gearbox swap.

You have options a plenty for gearing anyway - from 3.73 you have 3.9, 4.11, 4.6 and 5.12 diff centres on top of Rockhopper series 1, series 3 and 1 litre transfer cases.

With a Vitara starting on 5.12's and 1.000:1 high well you're kinda stuffed.

The question for me is dual T/case, blank off the Vitara T/case and runa sierra T case, or run a modified Sierra gearbox and T/case.

In my case I think dual T/case may be easiest, but it may be easier to ditch the Vitara case and substitute a Sierra one, due to rear driveshaft andgle and the Vitara front driveshaft output being in the way.

Anyone who's managed a dual tcase on a Vit have any advice?

Further investigation will be made before I publish a result, but the gearing will not be right without twin diff centre swaps.

Given I have only Calmini R&P's at $2k to reduce high I think it's worth looking at.

Posted: Mon Oct 13, 2003 10:03 pm
by mud4b
thanks greg.the very bottom lines of your post is what i wanted to know.

im not worried about gearing.just how the duel cases work.

Posted: Sun Nov 02, 2003 9:34 pm
by SAWZALL
Wouldn't go near them. More crap to go wrong when a S3 is (usually) heaps of gearing

Posted: Sun Nov 02, 2003 10:20 pm
by Beastmavster
uphiir wrote:Wouldn't go near them. More crap to go wrong when a S3 is (usually) heaps of gearing


I have found a suitable dual transfer case option, with some benefits and some downsides.

Benefits: Near perfect high ratio and good low reduction, Cheap, capable of dealing with massive (for a zuk) power outputs, rear output height reduced by about 4" actually improving driveline angle

Disadvantages - output on left for front and rear (more an issue for front), low ONLY 72:1 crawl ratio, crossmember in the way for second t/case.

Not publicising it till I have one in - I don't wanna see the price go up.

Still tight on money with the missus having done her knee..

Re: DUEL T-CASES OR NOT

Posted: Thu Nov 06, 2003 4:21 pm
by Luigi Malone
mud4b wrote:can anyone tell me the benifits of having duel t-cases or is it better to just go the series 3 rockhopper?im not worried about the cost or time.


Seeing this post has made me think, i've seen a lot of posts on ORC & POR about all the new doublers on the market.
Has anyone here tried to put a vit t/case behind a sierra transmission and in front of the t/case? As Spidertrax and Trail Tough have done.
Seems like a shipload of money to me.
My 97:1 is good enough. But a 1:1 option on road would make life less buzzy.
LM.

Posted: Thu Nov 06, 2003 5:02 pm
by greg
since it is possible to put a sierra transmission behind a vitara engine (via an adaptor plate), it would make sense to think you could do it the other way around with a vitara tranny and sierra engine.

This would allow you to run the non-divorsed vitara x-fer case if you wanted.

And i guess that would put you closer to running duel x-fers without running two sierra ones.