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Unread 05-07-2012, 02:23 PM   #16
kickingprop
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Subscribed!

I'm hoping to do a similar swap with a cummins B3.3T or QSB3.3T down the road on my Scout.

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1985 CJ7 Project
Phase One : 5.3L Vortec/4L60E, Moser axles for AMC20, Twin Stick'd Dana300 - Completed
Phase Two: Bedliner, Rollcage, Seats, BESRK Rear Bumper w/ tire swing, Soft Top, and a few other goodies - Mostly Complete
Phase Three: Waggy 44 front, Scout D44 Rear, 4.56's, ARB's (F/R) SOA with YJ Springs, 35x12.50x15 BFG MT - Not Even Close to beginning

Also a mostly rust-free 1970 Scout 800A That I'll get to start working on someday...

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Unread 05-08-2012, 03:45 PM   #17
Dre40
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well the Hunt is on for either a 14B rear or a Dana 60 I called a few JK but they want over $350 for an axle. ugh so I'm going to keep looking. I found one on CL but he wants $200 for it and its 4:10 gears and the spiders have been welded. I found a D60 for $200 to but its also 4:10 gears. Not sure about the front if the D44 is good enough for now or if I should look for a set?
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Unread 05-08-2012, 05:10 PM   #18
jeepwhore
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How big of rubber are you gonna run?

Since the 465 doesn't have O/D I'd just go with the more common 4.10's rather than waiting to find one with 4.56 gears in your price range. The 4.10's will help keep the rpm's down on the highway (especially since diesels are lower revving engines) and the cummins will have plenty of torque to get you moving. The 465 has the granny low 1st so the 4.10's won't be too high for crawling either.

Just a thought anyway.
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Unread 05-08-2012, 06:45 PM   #19
Dre40
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Well I'm probably going to be running either 35s or 37s depends on what I can afford. Now I thought 4:10 wouldn't be a good gear to run because it increases the RPM. I'm currently running 4:10 in my YJ and after I installed them my RPM increased by at least 500 RPM or more. but I'm running 33 so maybe 35s or 37s might be a different story..
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Unread 05-09-2012, 09:00 PM   #20
twiisted71
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Hey Dre

I'm building much the same rig (remember). Play with a RPM calculator to see what will make you happy. I'm going with 3.73s and 35"-37"s and I'm running the ZF with OD. You want your cruising RPM around 1800 highway. around town at lower speeds I'm looking for around 1500 (less wind resistance so less HP needed).
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Unread 05-11-2012, 06:13 AM   #21
Dre40
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well I found a 14 Bolt on CL the guy want $200 for it. its complete drum to drum has 4:10 gears and the spiders where welded. so do you think its a good deal or should I keep looking?
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Unread 05-11-2012, 06:22 AM   #22
kw89425
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Well around here thats high. You might try to barter
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Unread 05-11-2012, 11:24 AM   #23
twiisted71
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If its going to be trail only sure. If not you'll need to regear as 35" tires, 1:1 final transmission, and 4.10 rear gears gives a 2362 RPM at 60. If you have to regear I'd keep looking for a better ratio axle. Gears, install kit, headaches are all going to add up quick. This is why I bought a 11.5" AAM, I wanted a 14 bolt or Dana 60 (plenty strong for a JEEP) but this one came along with 3.73s and disc brakes, and less than 50K miles with a G80 gov-lock. Since this axle is welded that could make street handling on a short wheel-base rig, I'd probably pass on this one. If the JY has a decent axle with the right ratio for you and possibly disc brakes for $350 I'd def. go that route before I'd try to save $150 and NOTHING be right except the housing.
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Unread 05-11-2012, 11:36 AM   #24
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Quote:
Originally Posted by twiisted71
If its going to be trail only sure. If not you'll need to regear as 35" tires, 1:1 final transmission, and 4.10 rear gears gives a 2362 RPM at 60. If you have to regear I'd keep looking for a better ratio axle. Gears, install kit, headaches are all going to add up quick. This is why I bought a 11.5" AAM, I wanted a 14 bolt or Dana 60 (plenty strong for a JEEP) but this one came along with 3.73s and disc brakes, and less than 50K miles with a G80 gov-lock. Since this axle is welded that could make street handling on a short wheel-base rig, I'd probably pass on this one. If the JY has a decent axle with the right ratio for you and possibly disc brakes for $350 I'd def. go that route before I'd try to save $150 and NOTHING be right except the housing.
Remember its a diesel. 2600 rpm is good for that motor. My f250 holds 2500 rpm at 70 and it holds 55mph at 1700 rpm with plenty of get up and go.

Ben
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Unread 05-11-2012, 12:09 PM   #25
Dre40
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That's why I want to keep the 3:73 because I did a calculation last night and looks like if I'm running 35s my RPM will be in a good range. now I'm not afraid of Regearing because I have done it several times. So im going to pass on the welded one and keep looking.. I'm going to try calling more JK around here to see what they have..
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Unread 05-11-2012, 07:29 PM   #26
twiisted71
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Quote:
Originally Posted by benullman View Post
Remember its a diesel. 2600 rpm is good for that motor.
Umm, NO that is wrong. 2600 is pretty much up against the governor on a stock 3.9-4.5 4BT. They like to be in the 1700-2000 RPM range. People will put higher spring kits to raise the governor speed but that is mainly to just give more RPM range while shifting or for racing applications. While not Detroit Diesel 71 series low rev engines neither are they Mercedes or yanmar "modern" automotive high speed diesels that like to rev. They are based off an industrial engine.
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Unread 05-11-2012, 07:40 PM   #27
benullman
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Quote:
Originally Posted by twiisted71

Umm, NO that is wrong. 2600 is pretty much up against the governor on a stock 3.9-4.5 4BT. They like to be in the 1700-2000 RPM range. People will put higher spring kits to raise the governor speed but that is mainly to just give more RPM range while shifting or for racing applications. While not Detroit Diesel 71 series low rev engines neither are they Mercedes or yanmar "modern" automotive high speed diesels that like to rev. They are based off an industrial engine.
I apologize! You are correct. I'm used to the 3k springs in my 5.9. Sorry about that. Yeah these engines are made for serious power not rpm. Disregard that post!

Ben
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Unread 05-12-2012, 11:22 AM   #28
Dre40
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Look at the score I just made. It's an 04 14 bolt out of a 2500hd with disk brakes all ready .. It's 4:10 with a Gov lock? So I will have to re-gear...
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Unread 05-14-2012, 04:02 PM   #29
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Well now I need to find some 8 lug Rotors and spindles to convert my D44 to 8 lug. Dropping the frame at the sandblaster Thursday to get blasted...
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Unread 06-22-2012, 07:44 PM   #30
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Well I got the 8 Lug hubs and backing plate for my D44 and I got the frame back from the sand blaster.. time to start welding..
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