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rsholland
01-31-2003, 10:31 PM
Slightly off topic... but not really...

Giving new (& real!) meaning to "Cross Country!" and not your average soccer mom Volvo!

http://www.dakar2003.nu/

This Volvo was enter in this years Dakar race. It has portal axles* from the Volvo C-303 truck, as well as other running gear.

* = For those who don't know what portal axles are: They are any axle that, at the very end of the axle where it meets the wheel, there is a portal drop box (which contains a gear) which moves the hub and wheel centerline below the axle tube. The net effect is that you get MUCH more ground clearance. Portal axles can be had on IFS/IRS (Hummer H1, some Pinzgauers) or with solid axles (Unimog, Volvo C-303/C-306/C-308). This Dakar race Volvo has a solid portal axle.

I found this info in the latest issue of Petersen's 4Wheel & Off-Road magazine, which has a great article on portal axles.

Here's another link with some interesting off-roaders not often seen in the USA.

http://www.real4x4.com/

Hmmm... Can you imagine a Forester or a Baja with a portal IFS/IRS setup?!?! I'm sure it would to be constructed from scratch, but the results could be awesome!

Bob

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nomadtw
02-01-2003, 10:23 AM
uhh we don't have 'axles' in the sense of that

we have CV joints...

if you want more clearance youu're gonna need to lift the suspension, and if you want even mroe you're gonna have to lift the suspension and get a longer CV joint

rsholland
02-01-2003, 12:36 PM
Originally posted by nomadtw
uhh we don't have 'axles' in the sense of that

we have CV joints...

if you want more clearance youu're gonna need to lift the suspension, and if you want even mroe you're gonna have to lift the suspension and get a longer CV joint

Uhh, no kidding...

I posted the above link because: A) It's worthy of discussion, and B) this forum has been a bit slow in terms of discussions.

Who knows, maybe some backyard mechanic, who is a Subie nut, will come up with a portal axle-type arangement... In any case, it's an idea worth looking into.

Bob

Pipercub
02-01-2003, 10:28 PM
The driveline on a Hummer (for example) rotates "backward" so that as the truck goes forward the halfshafts are running as if the vehicle were backing up. This is because the halfshaft drives a gear that meshes with the gear that drives the wheel, reversing the direction of rotation. That means that for the Baja the drop box would have to be a three gear arrangement to restore the original direction of rotation. This would mean more expense but not much technical difficulty. The drop box could be integrated with the hub and lower strut mount and with the use of a longer lower control arm you would also be gaining a reasonable ammount of lift from the assembly.

I doubt we will ever see this because the expense of 4 gear box/ hub units would be very high. It is a shame because this would also be the ideal place to reduce the gear ratio to compensate for larger tires.

US2JDM
02-02-2003, 12:15 PM
Originally posted by Pipercub
The driveline on a Hummer (for example) rotates "backward" so that as the truck goes forward the halfshafts are running as if the vehicle were backing up. This is because the halfshaft drives a gear that meshes with the gear that drives the wheel, reversing the direction of rotation. That means that for the Baja the drop box would have to be a three gear arrangement to restore the original direction of rotation. This would mean more expense but not much technical difficulty. The drop box could be integrated with the hub and lower strut mount and with the use of a longer lower control arm you would also be gaining a reasonable ammount of lift from the assembly.

I doubt we will ever see this because the expense of 4 gear box/ hub units would be very high. It is a shame because this would also be the ideal place to reduce the gear ratio to compensate for larger tires.

I was just thinking the same thing about the gear ratio adjustment...but the extra hardware would also increase unsprung weight...I guess everything's a trade-off. :alien:

On a related note...I want a Pinzgauer and/or a UNIMOG...*drool* *drool*...I saw a Pinzgauer rolling around in some little town while on a road trip up north and almost peed myself.

:D

rsholland
02-02-2003, 12:26 PM
This is not a new idea. It's been around for some time. I wonder if Subaru ever experimented with the concept?

As we all know, one of Subaru's hallmarks is innovative thinking and engineering. I would love to see Subaru (someday) bring to market a vehicle that would go head-to-head with the Jeep Wrangler and Toyota FJs, using the up-coming Forester/Baja low-boost 2.5 turbo (turbo-diesel boxer too!), AWD with a 3-speed transfer case (High Range, Medium Tow-Haul Range, Deep-Low Range), and IFS/IRS/portal axles.

Such a vehicle would have incredible ground clearance, and if it were designed with a long-travel suspension, nothing would stop it.

Bob (who is always dreaming...)

Pipercub
02-02-2003, 08:12 PM
DING DING DING.... YOUR ORDER IS READY.

http://www.subarubrat.com/PICS/flares1.JPG



They DID make such a vehicle, you just have to take it out of the box it shipped in.

rsholland
02-02-2003, 08:38 PM
Are you saying that was built by Subaru? Or, was that built by some aftermarket company? Besides huge tires and gobs of ground clearence, what's the running gear like?

Bob

Pipercub
02-02-2003, 08:54 PM
Yep, that is the Subaru BRAT, sold from 78~87 and there were two generations, 3 if you count the cosmetic change from the 82 dual rectangle to the GL quad rectangle deadlight scheme.

The BRAT above is mine and I have allot of info that answers most of your questions up on my site. It has long travel 4 wheel independant, a supercharged 6, full tubular lift/subframe, and all sorts of other mods. As modded as it is, everything is an extension of what was already there, not a total redesign.

www.SubaruBrat.com (http://www.SubaruBrat.com)

Rotorflyr
02-03-2003, 12:00 AM
Originally posted by Pipercub
The BRAT above is mine and I have allot of info that answers most of your questions up on my site.

Do ya have the jump-seats in the bed?....hehehe :alien:

Pipercub
02-03-2003, 12:20 AM
I have them, but they are in the shed. Dual batts, fuel cell, and a spare take up all the bed space.

rsholland
02-03-2003, 08:06 AM
Originally posted by Pipercub
Yep, that is the Subaru BRAT, sold from 78~87 and there were two generations, 3 if you count the cosmetic change from the 82 dual rectangle to the GL quad rectangle deadlight scheme.

The BRAT above is mine and I have allot of info that answers most of your questions up on my site. It has long travel 4 wheel independant, a supercharged 6, full tubular lift/subframe, and all sorts of other mods. As modded as it is, everything is an extension of what was already there, not a total redesign.

www.SubaruBrat.com (http://www.SubaruBrat.com)

Ah, ha! So... "you" modified it, not Subaru. I was wondering if there was ever a "factory" vehicle like this, that was ever shown, or even considered?

Bob

Pipercub
02-03-2003, 08:47 PM
The way I see it, that is how the BRAT should have come from the factory. It is a very capable vehicle stock, like a WWII willys jeep, but it's true potential is greater than delivered.

As far as I know Subaru has not actually prototyped a truck like that.

RacingBlue
02-28-2003, 11:17 AM
Portal axles were under the skirts of old VW vans in the swing axle configuration not IRS. Also used on the earliest 181s from europe (that's the Thing). The later Mexican mfged ones were IRS without them, too expensive. Also used on the Porsche protype NATO jeep that never was (1950s). Quite rare, but there are a few in the US. Ditto the WWII VW Schwimwagon and Kubelwagon. Very heavy in the unsprung weight department, expensive and rather clutsy in design IMHO.

RacingBlue
02-28-2003, 11:33 AM
The low range Subaru trans used in the Oz Forester with the smaller engine is quite ingenious being that it is all in the transmission. No portal axles or transfer case mumbo jumbo. It is simply a split first motion shaft with a reverse-like idler gear that handles the reduction. Very straight forward, light weight, inexpensive and it gets the job done. As I recall that's the same way the Brat low range gear was handled as well.
I would guess why it is not in current US versions is that there is no practical need with the larger 2.5 SOHC engines and the way the US product is used. Also a high percentage are sold with autos which have the torque multiplyer effect through the torque converter.

Just trivia.