cowboy_tech
1/2 ton status
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T-case & Doubler comparison thread...
- Thread starter TheBeast_88K5
- Start date
The Magnum box fixes this problem and gives you a true 4 speed since the shaft between the underdrive gearset and the 205 is now big enough to support the underdrive's torque output. It's also 6.25" long, all new parts, user indexable, 33#, and generally pisses excellence.
behind a TH350:
So how is it different than NWF's Black box? Looks just like it and appears to use the same gears judging by the ratio options.
mrdrinksalil
1/2 ton status
hopefully its cheaper. 
Looks like it's 1" shorter and about 14lbs lighter and hopefully a bit cheaper.
Stephan, I love what you guys did for the Magnum box, Ultra cool!
Could I ask where you got your Intermediate shafts?
If you prefer not to say I understand...
The reason I ask is the outfit that made mine has placed their "lifetime Guarantee against breakage" on it.
I think Chris and I had a couple of private conversations about this. I was just curious if you guys were using the same manufacturer.
I'm more worried about the outer case exploding than I am the intermediate shaft. If I am forced into rebuilding the doubler due to breakage of any kind, I will be looking for a way to make the case from machined steel...
That's a cute little "lifetime warranty" on that bottom shaft.
We're going with YOU DON'T NEED A WARRANTY!
Seriously now though, that's why we call it the MAGNUM. The planet hub spline is the weak point in the system and it's over 1 5/8". You can't break it. This lets you treat this system as a true 4 speed, meaning you can do whatever you want in any gear. Any other system is going to have limitations on how hard you can run in the 2.72 low gear, this one does not.
It's not built to be cheap or compete with any other underdrive, it's built to be the strongest most versatile transfer case system there is and the price really isn't out of line for what it does. In fact we might be selling it cheap to start with. Complete Magnum box WITH input conversion for the NP205 is $1990. It comes with free TCT too.
gonefishin
1/2 ton status
Subscribed for all the info I can get while I wait for ord to finish the round 205/241 doubler kits. Anyone know if its made for the long or short input on the 205? I am trying to get everything ready
I want one and not just because I can tell people my box is a MAGNUM!
Nice piece but the good ol doubler still wins for cheap and awesome.
Nice piece but the good ol doubler still wins for cheap and awesome.
so much to regurgitate here, and I need to call it for the night.
clif notes:
you can't really compare pricing for any of this stuff to an atlas when what you end up with has the strength of a 205 and multiple gear ratios. Having 2 or more different low ranges really does make a difference.
We have the "241 stock rotation to fig8 205 2 inch up rotation" kits are ready to ship right now. Other versions are drawn and design work is finished, it's a matter of getting it all in production. Rotations options are pre-set since the bolt patterns all have to mesh.
any underdrive system using a 32 spline intermediate shaft is not what I would consider a true 4 speed in anything big since the intermediate shaft is always a weak link when the front box is in low and the rear is in high. Not everyone will break it but everyone should know about it.
The Magnum box fixes this problem and gives you a true 4 speed since the shaft between the underdrive gearset and the 205 is now big enough to support the underdrive's torque output. It's also 6.25" long, all new parts, user indexable, 33#, and generally pisses excellence.
behind a TH350:
pic of the "Chop Box" display from EJS:
Yeah, well. Great
.Cool move, now that I've finally convinced myself that a 203/205 doubler isn't really in my cards
, and decided to ditch that semi-rebuilt 205 I happen to have, and got a 241 with the game plan to do a slightly clocked t'case with an SYE. Where was this when I wanted an Atlas for my 50th birthday, just to find out that an Atlas doesn't sufficiently lubricate the planetaries in 2hi at 75mph on the freeway?
Well?
In a perfect maneuver of distraction, I'm now committed to putting a 5-speed in my wife's FJ40....
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Short input
gonefishin
1/2 ton status
Oh that sucks I already twin sticked it sealed it up and filled it full of oil
Where was this when I wanted an Atlas for my 50th birthday, just to find out that an Atlas doesn't sufficiently lubricate the planetaries in 2hi at 75mph on the freeway?
Really?
There are a couple of guys running atlas 4 speeds in the desert/koh that run the 2:1 all the time with like 4:10 axle gears and 4 speed autos. then in the rocks they shift the planetaries in.
Meaning they run the planetaries in hi for desert racing and they have held up for several years now. One of them completed V2R in 09' which was a 1,000 miles.
In all honesty Micheal for what you do and like to do with your blazer a 241 SYE is good. A 205 would suck a bit more gas and shorten your range and I know that you like to drive your truck to and from the trails and also do longer exploring trips.
A happy wife is a happy life. Just keep saying that over and over and over
mrdrinksalil
1/2 ton status
Ok so cliff notes..
Correct me if I'm wrong. On the Magnum box:
Correct me if I'm wrong. On the Magnum box:
- Stronger than an Atlas 4speed and NWF Black Box because if the intermediate shaft.
- ~$1000 Cheaper than an Atlas 4speed because of readily available NP205
- ~4-5" longer than a Atlas 4Speed and ~33lbs heavier (~100lbs Lighter than a 203/205)
- generally pisses excellence
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TheBeast_88K5
Banned
Man,.... This thread really panned out.
Ok so cliff notes..
Correct me if I'm wrong. On the Magnum box:
- Stronger than an Atlas 4speed of Black Box because if the intermediate shaft. And because the 205 is bigger and beefier.
- ~$1000 Cheaper than an Atlas 4speed because of readily available NP205
- ~4-5" longer than a Atlas 4Speed actually about 2" longer than the shortest atlas4, similar to the "long tail version"and ~33lbs heavier (~100lbs Lighter than a 203/205)comparison weights get kind of fuzzy with iron vs. alum. adapters and such but this is about right
This kind of falls in the "stength" catagory but the Magnum lets you use the 2.72 low as hard as you want without worry about the intermediate shaft strength- generally pisses excellence
massaged it for you a little
mrdrinksalil
1/2 ton status
Nice. So when do you put mine up in the parts giveaway board?!
Stephen beat me to it.Ok so cliff notes..
Correct me if I'm wrong. On the Magnum box:
- Stronger than an Atlas 4speed of Black Box because if the intermediate shaft.
- ~$1000 Cheaper than an Atlas 4speed because of readily available NP205
- ~4-5" longer than a Atlas 4Speed and ~33lbs heavier (~100lbs Lighter than a 203/205)
- generally pisses excellence
I'm not sure if it is "stronger" than an atlas 4 speed cause I don't know how they are linking the planet box to the gear box in the atlas, However it certainly is NOT weaker. Yes in the case of NWF girth wins
Looking at advances site they have a a 16.75" length and a 18.75" length. Those have to do with the output style. but I don't think that includes the transmission adapter, so add some amount of length(probably varies by transmission) to the atlas lengths. So i say the lengths are probably about the same at the end of the day.
I have been fondling the parts for the last few months when I stop by the shop a few times a week. It's nice to see them moving out the door and the design work finishing.
I probably fondled your magnum before you did
mrdrinksalil
1/2 ton status
I think this is the old atlas 4speed with the short output. Not sure if it got longer.
http://www.pirate4x4.com/tech/billavista/PR-Atlas/images/Atlas%20length%20with%20yoke.jpg
http://www.pirate4x4.com/tech/billavista/PR-Atlas/images/Atlas%20length%20with%20yoke.jpg
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And now for some general underdrive system tech.
Any time you underdrive a transfer case you have to consider the torque capacity of the intermediate shaft and transfer case input. It's intuitively obvious that anytime you double or triple the input torque on the input of a transfer case you stand a chance of breaking that input and this torque increase is exactly what you do with an underdrive.
So what we look at with a 205 specifically is that you have two 32 spline output shafts that are good for about 4000 ft-lb of torque (to use a round number) each. If the 205 is in high range you can put 8000 ft-lb into the 205 to reach the breaking strength of both outputs. Obviously this 8000 ft-lb is way over the strength of a 32 spline input since a 32 spline input is only good for the same 4000 ft-lb of torque. This is why it's bad to run most underdrive systems with the front box in low and the 205 in high
Let's mix this up and put the 205 in low range. Now we have a 2:1 torque multiplication between input and output so the 8000ft-lb that the output shafts can support can be generated by only 4000 ft-lb from the input.
input at 4Kft# * 2:1 gear reduction = 8Kft# split between the two outputs.
Fortunately the good old 203 doubler system has 2:1 gear ratios in both boxes so there is no reason to ever run the 203 in low and the 205 in high. This makes it easy to run it right all the time and as such it's a really tough system.
The problem comes in when we start using planets that are a 2.72 reduction. Now that front gear reduction is useful to use by itself and it's also a deeper reduction so it's harder on the intermediate shaft....
Any time you underdrive a transfer case you have to consider the torque capacity of the intermediate shaft and transfer case input. It's intuitively obvious that anytime you double or triple the input torque on the input of a transfer case you stand a chance of breaking that input and this torque increase is exactly what you do with an underdrive.
So what we look at with a 205 specifically is that you have two 32 spline output shafts that are good for about 4000 ft-lb of torque (to use a round number) each. If the 205 is in high range you can put 8000 ft-lb into the 205 to reach the breaking strength of both outputs. Obviously this 8000 ft-lb is way over the strength of a 32 spline input since a 32 spline input is only good for the same 4000 ft-lb of torque. This is why it's bad to run most underdrive systems with the front box in low and the 205 in high
Let's mix this up and put the 205 in low range. Now we have a 2:1 torque multiplication between input and output so the 8000ft-lb that the output shafts can support can be generated by only 4000 ft-lb from the input.
input at 4Kft# * 2:1 gear reduction = 8Kft# split between the two outputs.
Fortunately the good old 203 doubler system has 2:1 gear ratios in both boxes so there is no reason to ever run the 203 in low and the 205 in high. This makes it easy to run it right all the time and as such it's a really tough system.
The problem comes in when we start using planets that are a 2.72 reduction. Now that front gear reduction is useful to use by itself and it's also a deeper reduction so it's harder on the intermediate shaft....
Advance had a re design of the 4 speed. They may have added length at that point. I could see pictures floating around of the old one still.
You pic doesn't work. Advance has the lengths on their website, I just don't know if that includes a transmission adapter or not.
I think the ORD length does. The adapter is built onto the range box.
You pic doesn't work. Advance has the lengths on their website, I just don't know if that includes a transmission adapter or not.
I think the ORD length does. The adapter is built onto the range box.
