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Just kickin around an idea... Double Subaru Tcase (twinstick?)

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well, ive been kicking around the idea of a double tcase setup on a subaru (subarus tcase of course)

 

What I have going through my head: (hypothesis)

 

1. Install D/R tcase to the BACK of another D/R tcase (yes i know, input/output shafts my not be correct, same with the bolt patterns on the cases... im sure this might be the hard part to figure out, but of course, were not there yet..)

 

2. 4low in the front tcase, would activate low range and send power to the rear tcase

 

3. 2wd selection in the rear tcase means, power sent from the front tcase is sent to the rear tcase, but is not transferred through to the driveshaft.

 

4. 4hi selection in the rear tcase means, regular 4wd (4 low technically since the gearing is reduced)

 

5. 4low on the second tcase, activates another low range set of gears.. also, sending power through to the driveline.

 

NOW! I did just wake up, and my math could be wrong, but this would equal 1.4:1 in 2wd and 2.8?:1 or 1.8:1 in 4wd

 

What do you guys think? Has anyone ever tried this? I'd love to hear some feedback! Thanks.

The one major problem I see is that the transfercase portion on a suby trans axle just engages the rear drive shaft. The lower gearing actually happens right off the bat on the input shaft on the transmission, before the power can even get to the cluster of gears.

 

 

Matt

 

And also the two would yeild a 1.96:1 low gear.

  • Author

if its anything like say.. an NP241.. then yeah, the planetary gears are in front (the input shaft actually is connected to the planetary gear set in this particular tcase)...

 

1.9 whatever:1 would be awesome!

if its anything like say.. an NP241.. then yeah, the planetary gears are in front (the input shaft actually is connected to the planetary gear set in this particular tcase)...

 

1.9 whatever:1 would be awesome!

No planetary, just regular gears shifted by a shift fork, living in the front diff housing.

gearbox.jpg

 

This may shed some light on the matter. Good thinking though!

id like to find a way to make the 2wd mode from fwd into rwd. i wonder if its possible

Uhhhh are you gonna run the driveshaft out the back (with double reduction) and the CV's in front (only the single internal reduction of the front DR box I think)

 

You need to find a way to have the double low range work for both ends of the car. Using the nissan setup with 2 subie rear diffs makes sense because everything passes through the nissan case and goes to the diffs from there.

 

I like your idea, just find a way to connect the front diff to both DR boxes and it could work?

  • Author

Thanks mudrat,

 

I see how it wouldnt work.. thanks.

 

darn wishfull thinking..

We need new ideas, this is all good. Too bad it wouldn't work.

The weight would be a problem with a setup like the dual dual / trannys and associated drivelines.

 

Seems to me the best we can do at the moment is the divorced transfer case.

We need new ideas

 

Yeah, its not a new idea though. ;) Divorced transfercase setup is how we get two tcases into a Subaru.

  • Author

Yeah, but its with nissan... I'm a subaru guy.. not a nissan guy.. thats why i mentioned subaru tcase..

 

Just wouldnt seem right knowing I have nissan parts under there..

  • Author

Mudrat, your the machinist.. make us some new gears for the tranny/tcase!!!

 

I know, probably easier said than done

get a lift and big tires first. thats the first step.

low range is great by itself, just give her some more power, or throttle.

  • Author

Power? Im runnin a 9.5:1 turbo here.. throttle? HA! i dont have problems there..

 

I have problems with the gearing! This isnt a thread about ways to get around the gearing problem.. its a thread to get better gearing.

 

I suggested to mudrat to maybe make a new gearset for the subarus, since he is the guy putting in LSD's in front diffs and making adapter plates for EJ/EA... he's obviously got more experience in the D/R 5 speeds than probably 95% of us!

 

Anyway.. If I sounded a little aggrivated with not having access to aftermarket gearing.. its because i am aggrivated lol..

Power? Im runnin a 9.5:1 turbo here.. throttle? HA! i dont have problems there..

 

I have problems with the gearing! This isnt a thread about ways to get around the gearing problem.. its a thread to get better gearing.

 

I suggested to mudrat to maybe make a new gearset for the subarus, since he is the guy putting in LSD's in front diffs and making adapter plates for EJ/EA... he's obviously got more experience in the D/R 5 speeds than probably 95% of us!

 

Anyway.. If I sounded a little aggrivated with not having access to aftermarket gearing.. its because i am aggrivated lol..

 

And just so you know..... The mudrat who posted above ISN'T the one doing the phantom grips into Trannies, or doing EJ/EA adapter plates, thats Mudrat79, not 4x4Mudrat. (sorry 4x4mudrat, maybe you could still figure it out, just had to point that out:) )

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