Another dual case scenario

Here we go. I've searched on most any jeep/4x4 board you can find and have been following the recent post concerning the EB20/klune setup.

Here's what I'm building right now: '86 MJ longbed. 2.5L from a '94 YJ, AX-4 tranny, 231 t-case. HP-44/9" 4.56 gears. 36" TSL's.
Basically gutted...no interior other than seat. steering column and that's it....no bed either so this thing should be pretty light. This is going to be a 99% trail rig...only on the street to get me there which is about 10 minutes from home.

I know the 4.56 gears should be deeper...BUT I would rather try to get the other gears (t-case etc) lower since the axles I found already were geared.

My thoughts are this...putting in a stock samurai divorced case behind the 231. Since the sammi cases have a 1.4:1 high range and a 2.24:1 low...I would technically have 4 low ranges. 1.4:1, 2.2:1, 3.8:1, and 6:1. This would be terrific as with that many gear choices (I'd be shifting like mad) I would have enough to choose for most any terrain and the 4 bngr would be happy.

The 4 crawl ratios would be 24:1(probably good for higher speed stuff), 39:1 and 66:1 (good for most any easy to moderate where 'crawling' isn't really needed), and then 106:1 (for the slow stuff if needed.) I would also get 2 low out of it as the 231 only acts like a crawl box.

I also know the LWB MJ has plenty of room to do this with 119" wheelbase.

Now without bashing the sammi case (it's the least expensive as it can be had for under $200 ready to bolt in)...what are some thoughts on this?

How is the Sammi case constructed? It will have the multiplied torque of the engine, tranny & 231 T-case being fed into it. If it was only designed for a tiny 4-cyl Suzuki engine it may not be strong enough. OTOH, I know nothing specific about it, so if you think it is strong enough then by all means it sounds interesting. A beefier option would be a divorced Ford NP205, which may be hard to find. Good luck!

I have seen (not owned) the sammi cases hold up behind the vortec 4.3 V-6...that's a lot more TQ than the jeep 4 bngr BUT you are right...having the TQ of the tranny and 231 going into the sammi case is ?? at best. It is gear driven but I'm not sure 100% on strength.

I do like the 205 option...but there huge and heavy. Fitment would be doable...but as you said finding one...

i question the strength of the sammi case, but i don't have much basis for that except everything on Sammi's is just so small.

my one big question is what are you going to do for driveshafts and locating the t-cases? if I remember correctly, Sammi cases have front and rear outputs on the passenger side. The Ford axles will be driver's side front, centered rear. If you flipped the case over (not sure how easy that is) so you had 2 driver's side outputs you would have to get the front driveshaft around the 231 and the rear shaft around the gas tank.

Yeah Brett...it's the strength of the sammi case...and the driveshaft issues that I'm not certain on.

I thought (think) the sammi case is drivers side drop...just like the 231...but again I'm not 100% certain.

This is probably something I won't do right now...I'm just looking for some thoughts on it and maybe some other options...but the front driveshaft issue is going to be the toughest to get around if I use 2 whole t-cases vs a crawl box/t-case setup. I suppose the 231 could be clocked WAY up to try and allow the front DS to go above the tranny cross member...but that may be more trouble than it's worth.

Then again once this thing is together I may just save my pennies for a crawl box and atlas case...who knows

BrettM said:

the rear shaft around the gas tank.

Click to expand...

Forgot to add the tank will be mounted right behind the cab between the framerails as I will not have a bed on the truck.

okay, i just double checked. Sammi diffs are both on the passenger side. good luck getting that to work.

get a divorced 205, 300, or forget the divorced case idea.

The 205 will weigh almost as much as the motor!!! J/K...but it will be indestructible behind a mighty 2.5!! (I'm not raggin' the 2.5..I have one in my XJ.)

Thankyou for confirming that Brett...that nixes the sammi case for sure.


Oh-well...I'm sure we'll come up with something if the extra gears are needed at all.

043500 said:

My thoughts are this...putting in a stock samurai divorced case behind the 231. Since the sammi cases have a 1.4:1 high range and a 2.24:1 low...I would technically have 4 low ranges. 1.4:1, 2.2:1, 3.8:1, and 6:1. This would be terrific as with that many gear choices (I'd be shifting like mad) I would have enough to choose for most any terrain and the 4 bngr would be happy.

Now without bashing the sammi case (it's the least expensive as it can be had for under $200 ready to bolt in)...what are some thoughts on this?

Click to expand...

I am a former Suzuki guy.

BAD, BAD, BAD IDEA!

The Sam case was designed to deal with ~80 lb-ft of torque from an engine (say 3.652 first gear x 80 lb-ft = ~300 lb-ft). The suzuki engineers are pretty good guys so lets say at the limit they designed for an engine that is capable of 50% more power, hence 120 lb-ft at the engine or ~450 lb-ft at the input at the t-case.

Last I read, I think the 2.5 made ~135 lb-ft of torque stock. First is ~4:1. That's 540 lb-ft before you fit the first transfer case. 2.72 x 540 = ~1470 lb-ft going INTO the Sam t-case.

I wouldn't even attempt mall crawling with it.

Suzukis are cool, but they are really toys compared to these kinds of upstream drivetrain components.

Oh, did I mention this is a really BAD IDEA? These cases barely stay together when doubled behind stock suzuki stuff like Sidekick t-cases or another Samurai t-case.

By the way, the case is ALUMINUM, passenger side offset front and rear and has provisions for a power take off on the back. It's a neat little case but not up to big torque upstream. The aftermarket makes a lot of different ratios for it: 4.1:1, 6.2:1, 8:1 and few ratios thereof.

By the way, what you have in mind is a BAD IDEA.

Did I mention it was a bad idea?

r@m

Root Moose said:

I am a former Suzuki guy.

BAD, BAD, BAD IDEA!

The Sam case was designed to deal with ~80 lb-ft of torque from an engine (say 3.652 first gear x 80 lb-ft = ~300 lb-ft). The suzuki engineers are pretty good guys so lets say at the limit they designed for an engine that is capable of 50% more power, hence 120 lb-ft at the engine or ~450 lb-ft at the input at the t-case.

Last I read, I think the 2.5 made ~135 lb-ft of torque stock. First is ~4:1. That's 540 lb-ft before you fit the first transfer case. 2.72 x 540 = ~1470 lb-ft going INTO the Sam t-case.

I wouldn't even attempt mall crawling with it.

Suzukis are cool, but they are really toys compared to these kinds of upstream drivetrain components.

Oh, did I mention this is a really BAD IDEA? These cases barely stay together when doubled behind stock suzuki stuff like Sidekick t-cases or another Samurai t-case.

By the way, the case is ALUMINUM, passenger side offset front and rear and has provisions for a power take off on the back. It's a neat little case but not up to big torque upstream. The aftermarket makes a lot of different ratios for it: 4.1:1, 6.2:1, 8:1 and few ratios thereof.

By the way, what you have in mind is a BAD IDEA.

Did I mention it was a bad idea?

r@m

Click to expand...

did you know that the 231 is aluminum?? as are Atlas's :gag:
its all in the case construction and design... not the material

bu dont get me wrong.. i totally see your point that sami cases arent designed to take 500+ ft lbs but ya.... damn near most transfercases are made out of aluminum

Root Moose said:

I am a former Suzuki guy.

BAD, BAD, BAD IDEA!

The Sam case was designed to deal with ~80 lb-ft of torque from an engine (say 3.652 first gear x 80 lb-ft = ~300 lb-ft). The suzuki engineers are pretty good guys so lets say at the limit they designed for an engine that is capable of 50% more power, hence 120 lb-ft at the engine or ~450 lb-ft at the input at the t-case.

Last I read, I think the 2.5 made ~135 lb-ft of torque stock. First is ~4:1. That's 540 lb-ft before you fit the first transfer case. 2.72 x 540 = ~1470 lb-ft going INTO the Sam t-case.

I wouldn't even attempt mall crawling with it.

Suzukis are cool, but they are really toys compared to these kinds of upstream drivetrain components.

Oh, did I mention this is a really BAD IDEA? These cases barely stay together when doubled behind stock suzuki stuff like Sidekick t-cases or another Samurai t-case.

By the way, the case is ALUMINUM, passenger side offset front and rear and has provisions for a power take off on the back. It's a neat little case but not up to big torque upstream. The aftermarket makes a lot of different ratios for it: 4.1:1, 6.2:1, 8:1 and few ratios thereof.

By the way, what you have in mind is a BAD IDEA.

Did I mention it was a bad idea?

r@m

Click to expand...

Good info to know...sounds like it's a bad idea LOL...seriously thankyou though for the info.

so does anyone think this is a bad idea?

I'm starting to get a bad feeling about all of this. Does anyone have some pics of the dual cases? I'm not fully understanding how this works.

witt said:

did you know that the 231 is aluminum?? as are Atlas's :gag:
its all in the case construction and design... not the material

bu dont get me wrong.. i totally see your point that sami cases arent designed to take 500+ ft lbs but ya.... damn near most transfercases are made out of aluminum

Click to expand...

Yes, I am aware the NV231 and Atlas are aluminum as well.

The Samurai transfer case housing looks like an egg shell compared to even the 231. I can't comment on the Atlas having never seen one apart - except from web wheeling.

r@m

I'm going to be doing something very similar with a 89 mj shortbox. I'm looking at this setup with makes alot of sence. there are a few details to work out but its a step in a good direction. http://www.pirate4x4.com/forum/showthread.php?t=330534

Just be careful of what box you put behind what...

If your using a 4.0 you end up with something like:

230 lb-ft * 4 (1st gear) * 2.72 (redux box) = around 2500 lb-ft

Looking at the New Venture Gear web site we see a handful of t-cases that could deal with that kind of torque, namely:

NV241,
NV261/NV263, and
NV271/NV273

(the 3 denotes push button shift IIRC).

Pretty slim pickins, really.

Would be interesting to see what the input torque values are for the Dana 20, 300, NP203 and NP205.

I don't know anything about the 271. The 241 can be found in most newer full-size trucks.

231 into a 241, or maybe a 231 with the 241 and wide chain mod downstream might be doable. I'd still be inclined to run a 241 though - the housing is probably stronger and there is no screwing around with mixin'-n'matchin' parts.

Just my spin.

r@m