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Kraqa
08-10-2005, 03:09 PM
Anyone looked into a NP231 front half mated to another NP231 or d300??

seen a few threads but anyone have experience? i'm goign to disassemble my np231 when i get it out of my truck see how this whoel thing works

zjeepin
08-11-2005, 07:57 AM
i think its called a KluneV

OverkillZJ
08-11-2005, 08:16 AM
i think its called a KluneV

Um, no! Klune is a secondary reduction box, but it's a product that stands on its own, not something that'll allow you to mate two 231's together.

Also, the klune costs that of an Atlas, which IMHO is just nuts...

zjeepin
08-11-2005, 10:00 AM
i know that the klune is a stand alone unit, i just don't see it being cost effective to mate 231's when you're not going to be able to twin stick it. Its still a cast aluminum case with a chain drive. I don't think there are many options for us with 231's. Im not saying I know what the end all of zj cases is going to be, i just don't see a doubled 231 being that great.

i really the way my rig crawls with the 5 speed and 2.72 low range. I would however like have just one more lower gear for sticky situations such as the klune. But i think if i can get a trans with a deeper 1st like 5:1 or 6 i'd be pretty happy with that. just my .02

I am certainly interested in how kraqas research turns out. good luck with that :supz:

OverkillZJ
08-11-2005, 10:03 AM
True, 2 chains could be a bit sloppy. :drinkers:

BigDaveZJ
08-11-2005, 10:35 AM
Why would you need 2 chains? All you would need is the range section of the 2nd case, not the mode.

Kraqa
08-11-2005, 10:54 AM
the NP231 doubler uses the front half of the first case (the range part, no chain) and then you woudl be able to mate it to any other case. You need to get the main shaft front the range case resplined so you can have it 31 spline for ford, 27 splin for chevy or 23 spline for jeep. All the adapter is, is a flat plate with counter sunk hole on one side and bolt throught holes on the other.

You could make the adapter plate out of some 1/2" or 3/8" plate in your garage. its the shaft thats expensive.

BigDaveZJ
08-11-2005, 10:54 AM
I bookmarked this off pirate a while back. Ghetto as hell, but definitely some ideas in there.

OverkillZJ
08-11-2005, 01:26 PM
I bookmarked this off pirate a while back. Ghetto as hell, but definitely some ideas in there.

I think ya forgot the linky

BigDaveZJ
08-11-2005, 01:28 PM
I bookmarked this off pirate a while back. Ghetto as hell, but definitely some ideas in there.

I think ya forgot the linky

Aww hell, and now I'm at work and don't have the bookmark. gawdamnit. The thread title was 231 doubler or something like that.

nmzj
08-12-2005, 08:22 AM
http://www.pirate4x4.com/forum/showthread.php?t=267239&highlight=doubler+np231

Kraqa
08-13-2005, 04:50 PM
it took me a while to find it. but this is what i was talkign abotu.

http://www.pirate4x4.com/forum/showthread.php?t=330534&page=1&pp=25
i'm going to look into getting the shaft made up. i knwo i can make that braket super cheep.

luvthejeep
08-13-2005, 09:14 PM
if you get that together kraqa, let me know- ill be yur first test dummie :partyman:

Kraqa
08-13-2005, 09:33 PM
i think i'l be the first dummy.

luvthejeep
08-14-2005, 01:01 AM
i meant second dummie, dummie

matts96zj
08-24-2005, 01:31 AM
i'm interested in this whole idea too, except; I'm not sure I'd wanna use a 231 as the main case. By having one as a range box, you're putting a shit-ton more stress on the second case than it was designed for & would probably make it puke it's guts pretty quick... just sumthin to keep in mind.

Kraqa
08-24-2005, 10:51 AM
oh the whoel idea of two 231's scares me. I'm putting it infront of a d300.

i just got a quote from OTT industries. $230 CDN for a custom heat treaded 4340 chromoly shaft. and the adapter i have estimated at abotu 75 or so. that pritty cheep for a doubler kit.

i wana get some wheelin in this year before i tear apart the jeep again. So for this winter i'm installign a doubler, twin sticked d300, front d60, TF999 tranny, re doing me front suspension. and douve tailing the front end. Shoudl be fun.

gonecheenin
08-30-2005, 08:00 AM
:spit:
I'm the "Buddy Jay" in that thread

Just so you have a real world opinion

The reason i've decided to go that route in doubling my ZJ stick shift conversion is I've watched Psychobilly beat his truck half to death with that setup on some nasty rock obsticals while running 38.5 x 15 x 15 Boggers, locked front and rear, with 4:56 gears, 5 speed manual, and a TBI 4.3
although i'm sure the 231 Chain will stretch over time, I've never once seen him break that doubler setup in well over a years hard use
(I''ve seen him break just about everything else though-LOL)
just avoid the 207 if you can because the high planaterys tend to blow out, but low seems to be plenty strong cause he never had a problem with low, just high

of course the key to that longevity is knowing you should never shift the front case into Low before the rear in a wheeling situation or else your putting way more torque into the second case then it was ever meant to handle
and i would never use the 207 as the second case in anything that had over 33's and a 4cyl, the 231 however will take and ass whuppin even behind a healthy V-8 in a heavy vehicle as long as you used a stronger second case like the 205

the beauty of that doubler setup is that you don't have to use an expensive modified shaft, the 27 spline input of the GM th350 & 700r4 versions of the 231/207/208/241 ETC....
is exactly the same cut and degree's as the 27 spline output of i think ALL the different 231/207 cases

i would not go the welded route myself
check out this link to some of the adaptors we're working on for this setup

http://p087.ezboard.com/fblacklistwheelersassociation40687frm7.showMessage ?topicID=1318.topic

In my case since it's gonna be a high speed application i am going to retain my front case pump and just trim the pickup tube back to work with the cut front output housing
see the illustrations

5's your pump
http://img.photobucket.com/albums/v83/BlackListWheelers/Tech%20pics/exploded%20views/231.jpg

17's the hose, 18's the pickup part
http://img.photobucket.com/albums/v83/BlackListWheelers/Tech%20pics/exploded%20views/np231.jpg

i'm then going to have a shop weld the original or new end caps on the cut case housing that will allow me to retain maximum strength and hopefully a leak free seal

hope this helps




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nmzj
08-30-2005, 10:15 PM
If I see this right, you are using the front and rear case housing and then putting an adaptor plate to bolt the 2 together.

Doesn't it make the doubler a little long?

Kraqa
08-31-2005, 12:51 AM
it makes it tremendusly long. check the link that i provided that is the version i think is way more practicle. only ads liek 7" or something.

gonecheenin
08-31-2005, 08:01 AM
I see what your looking into now

The version using the 2 complete joined 231's is fairly long, BUT it's not much longer at all then your standard automatic/NP208 setup from say a GM fullsize

for a SWB Jeep it would be nessacary to lengthen the wheelbase in the rear for sure unless you went the way Kraqa is

But in a Psychobillys 90 something S-10 short bed standard cab truck with the 2 complete 231's together behind the stock 5 speed with the 4.3 in the stock mount location and the rear end in the stock location with stock springs roughly a 112" wheelbase (he lengthend the front end when he put radius arms on it) he still has roughly a 3 foot or better rear drive shaft

you can't see it real well, but this pic will give you an idea of how decent his rear shaft still is

http://img.photobucket.com/albums/v83/BlackListWheelers/psychobilly/fland002.jpg