Topic: Double Down; crawler boxes

[FourbangerYJ]

Interesting.  I'm assuming they're not using a Klune also?

A friend of mine has a blem in his 2.5L with 38.5" and 5.38's and never had any problems.

Have any pictures?

None of them have Klunes or doubler of any kind. I'll see if I can round up a PIC.
The TJ is getting a Atlas 5.0 and the YJ is getting a Atlas 4SP.

Funny thing is the guy with the 4.2 YJ bought his Tera 4 to 1 kit from a guy that put in a Klune 4.0 and sold his Tera kit. He is using a 23 spline 2.72 231 behind his Klune. So far the 231 has held up. No HD chain, not sure that SYE he has.

[jagular7]

The d.d. Machine is the mfr we've been contacting. Duffy is working out the issues of the adapter shaft for basically all adaptable t-cases.

For cost, you can't beat the double low cost of the ddmachine and another t-case setup. Going with a D20 is a great step-up option, gaining
- driver's drop
- twin stick capable
- steel gears rather than chain
- yokes
- optional deeper gear set
- no longer than stock 231 case

Another option would be the 205, but that is a massive and heavy case.
- driver's drop (Ford)
- twin stick capable
- steel gears rather than chain
- large yokes
- optional deeper gear set
- slightly longer than stock 231 case

though you could keep a 231 behind all this.

For compound low, why worry about a 8 or 10:1 ratio with a 6:1 is rather cheaply easy to get to. Still running a 4cyl, the difference is negligable, I would think.

[Jeffy]

For compound low, why worry about a 8 or 10:1 ratio with a 6:1 is rather cheaply easy to get to. Still running a 4cyl, the difference is negligable, I would think.

The difference is that not only do you have 2.72:1 (or abouts), 4:1 and 10.66:1.  There are times when 2.72 is too high and compound low is too low.  

By only running a 231 doubler and a D20 you basically have 2.72:1, 2.46:1 and 6.69:1.  Lots of overlap between 2.72 and 2.46:1.

[FourbangerYJ]

I hardly use the 2.46 by itself. Even with 4.88's it's hard to keep the motor lit if it gets to rocky. I don't know how the Bronco guys did it back in the day :?:  The 4:1 gets used the most. Although I do find the 9.84 pretty handy at times as well. I found that with both boxes in low and the tranny in 3rd is about the same as just running the 4:1. It saves time and hassle of taking the D20 out of low.
The thing with having 2 boxes of gears to choose from is the choices it gives you. Having a sizeable split between the gears gives you more choices. I thought about getting some 3:15 gears for the D20 since I hardly use the 2.46 by themselves much. But that is not enough split between the ratio's for my tastes. And the 2.46 makes a great ratio for doubling. Although I think the 2.72 would be better.
Keep in mind that it really is not about having a 9.XX or 10.XX to 1 as a compound low. It's about having the ability to choose from 2.46 or 2.72 or 4 or 9-10 to 1. Depending on which T-case you use. If you only do the real rough stuff the deep single case gears would be OK. But if your choices in trails has a large variety then having a large variety of gears to choose from is the way to go.