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Discussion Starter #1
thanks for all the great info here. i have a 66 patrol project ive been working on fo 3 months now. 105hp 4bt,d60's(3.07),4 link front,sm 465/np205 36/12.5/16.5. im building it for a daily driver/camping/hunting rig,and some very lite towing.. am i shooting myself in the foot going with the sm465? can it work? i already have the t case crossmember mounted,but if its imperitive i go 5 speed than nows the time.has anyone had first hand experiences driving a 4bt with a 4 speed?
also,i love fabrication,so i would like to do compound turbos if there is any benifit. if there is no benifit what single would be recomended for an upgrade.thanks for the help. andy
 

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If you're running D60's with 3.07 gears (is that possible?!) and 35" tires the 4speed should be fine w/o an overdrive.
 

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yes,they are dana 61,s. i just say they are 60's cause they are pretty much the same axle and it saves me some explaining of what a dana 61 is. im not very good on a computer so i will ask my whife if she wiil help me get some pictures of it on here.thanks for the positive remarks. i feel me and my project will be right at home on this forum.iv been stressing about the 4 speed lately thinking i shoulda gone 5 speed. i guess we will see. any sugestions on compounds.id love to build a custom header with some twins!
 

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yes,they are dana 61,s. i just say they are 60's cause they are pretty much the same axle and it saves me some explaining of what a dana 61 is. im not very good on a computer so i will ask my whife if she wiil help me get some pictures of it on here.thanks for the positive remarks. i feel me and my project will be right at home on this forum.iv been stressing about the 4 speed lately thinking i shoulda gone 5 speed. i guess we will see. any sugestions on compounds.id love to build a custom header with some twins!
I was going to go with a T18A four speed because I already owned that setup, and the gear spread was 6.4:1. Then I realized that if I ever needed to downshift from 4th (1:1) to third (1.69:1), the jump in RPM's would be of 69% !! :eek: I sold the T18A and got a divorced NV4500. The jump from 5th to 4th is 27%.
 

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If you're running D60's with 3.07 gears (is that possible?!) and 35" tires the 4speed should be fine w/o an overdrive.
There was some 1st gen dodge with Cummins with the D61 front with the 3:07 gears rare but out there.

Thanks
CrewCab59
 

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Cool. I knew some of the dana 60 car rear ends had like 3.31 but nothing like 3.07. Most Truck axles I've seen are 3.73 and up but thats good to know :)
 

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Discussion Starter #9
so ant suggestions as to what turbo/turbos might work out for my aplication.im ready to buy but i prefer to do as little of the trial and error as possible. if i could get some ideas or first hand experiences it would probably save me some time and money. thanks
 

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D61s are D60 housings and D44 internals. If everything else is bombproof this is your weak link. Probably have to upgrade to D60s if your not light on the pedal:D Been reading where a lot of offroaders are tearing D44s up even with Warn alloy inners and other upgrades.4BT= hi torque
 

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D61s are D60 housings and D44 internals. If everything else is bombproof this is your weak link. Probably have to upgrade to D60s if your not light on the pedal:D Been reading where a lot of offroaders are tearing D44s up even with Warn alloy inners and other upgrades.4BT= hi torque
um.....i'm pretty sure you're off there. Thinking of the Dana 50 maybe? D60 internals can go in a D61 housing with a ring gear spacer. The D61 allowed for lower ratio gears like the 3.07's mentioned.
 

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Discussion Starter #12
d 61's are the same internals as the d60s.the pinion is just moved over to fit a larger pinion gear in.there is no way id put dana 44 behind this motor.although iv use d44's on other projects with great results.
 

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Wasnt thinking clearly, you are both right, was thinking of D50. My bad
 

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I drove a few hundered miles around town in my breadvan with the SM465. It definatly was not able to keep up with freeway trafic, but the power was good (empty most the time). Not sure what the axle ratio was, but nowere near what you want to run..

A 5 speed would definatly help out the daily driving. Plus could go a little deeper in the axles to help offroad around town. At the vary maximum you only have ~1500rpm to play with and that is about the jump from 3rd to 4th at 65mph (2100rpm if you upgrade the spring)

Play around with this gear ratio calculator it is one of the best on the web...
http://www.grimmjeeper.com/gears.html

IMHO with 3.07 and 36" tires I think you are not going to like the performance. Eventhough it is really light, it is a lot to ask...

What is your wheelbase? it might be a little difficult to get a NV4500 and 205 in there. I looked into doing a swap with my CJ-5 (wb ~83") and it would have been damn near impossible to get the combo in there without the engine well over the front axle.
 

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Discussion Starter #17
65scout4bt,thanks for the input.that was my oringinal concern(fiting it) ive got the engine pushed as far forward as i can and i moved my front axle forward as well for balance.
i also drove my step van 280miles to get it home.55-57 was my top speed.but it got there relitively quik. im getty a little frustrated.i hate backtracking on a prject.i think i will go measure some other combinations.also,i dont want to change axle gearing.it was a pain to find them with the 307's.and i wont swap the axles out because ive got hours of fab time in my front axle.i do plan on adding the 3200 spring.
other suggestions please.
 

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run it. it seems close to 39" tires, 4.56 gears and nv4500. 1st in the nv4500 wasnt friendly on the street and i never used it off road. heck the video of my old truck thats on youtube was done in 2nd, and with a np205 and a cpl858 cummins
 

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I was going to say the same thing as McInfantry, just run it, don't worry about it unless you have the time, $$, and energy to swap it out. With the 3.07 and the 36s you'll be fine, be able to cruise pretty fast actually. It is a light truck, I feel like the 4BTs almost like a load more than they like empty. I bet it will be great, in my opinion...

PS I love those old patrols. We had a few down here in Utah a few years ago I used to drive once in a while.. Sort of a like a Land Cruiser meets a Rover or something like that.. All of which I am fans of!
 
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