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posford's posbuggy planning, research, and criticism thread

posford

:flipoff2:
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​​​​​This is in no way Gen4x4 worthy, unless getting into the ghettofab thread counts :flipoff2: This thread is mostly for my organization of thoughts, and anyone else is welcome to jump in and tell me I'm a moron.

I'm a hoarder of parts, and have long said that I have damn near everything to throw together a basic bare bones crawler. Wasn't planning on anything at the moment but I get a PM the other day, and I wound up picking up a tube frame from another member who was about ready to chop it up. Looks very well built, pretty damn straight, gusseted where it matters, and unlike everything else I own, isn't covered in rust. He set it up for a CJ tub, leaf springs all around, 95" wheelbase, and roughed in the mounts for SBF/NP435/205 drivetrain. I grabbed the NP435/205 from him to help feed my piles of parts.

I had to go inventory my axle pile, I've got
2 86-97 Ford Dana 60s, one KP one BJ, both complete
EB width Dana 44 housing, drum brake outers for it
75 K20 Dana 44, missing everything spindles out for my Ranger.
F+R narrow track Jeep axles
F+R M715 axles still in a parts truck
Also have a 79 Dana 44/9" combo from a F150 that I need to go pick up.

I considered the KP60, but the front spring mounts are set for 32" spring perch width, and I'd rather not lose the turn radius.
Flirted with the EB axle idea, figured get an Explorer 8.8 to match, I have wheel adapters to get to 5x5.5. grind the wedges off and put perches on it, use the outers from the 79 Ford axle on it, already have a EB length chromo long side.
Seriously considering the Chevy Dana 44, machine the knuckle for high steer, use the use the 79 Ford outers, match to the 9" rear. Spring perches are already in the right location.
NT Jeep axles are too small for this
M715 axles are a backup plan, only because they're free, but that trucks still a roller for now and I'd have to bone it out before I steal its axles.
I think the 79 Ford Dana 44 center is fucked up, haven't looked at it too close, plus it has cast wedges and I don't plan to run coils.

A little side piece about my background. I'm a machinist with access to about anything I could ever need. I own a welder, I know how to use it, but I don't consider myself to be much of a welder, which is why I jumped on a mostly done custom frame. I was never going to be in a position to do that myself, but thankfully I have a close friend that is an fantastic welder, I can barter some work with him when I need some critical welding done.

Which brings me to my next part. If you've read this far you've noticed that I'm flip flopping between driver and passenger drop axles, which a passenger drop Ford drivetrain isn't a thing. I considered building an adapter to mate a SM465 to the back of my NP435, so I could run a married Chevy 205 for passenger side drop front axle choices, and I would stick to whatever 3.xx gears are in the axles I have. I'm concerned about the length of that with the 95" wheelbase. Now I'm considering taking the BW1345 transfer case I have kicking around, and cutting it up for a doubler, and mate it to a Chevy 205 to get passenger side drop still. But I think with a doubler as opposed to a double transmission I'll have 1 or 2 useful crawl gears versus 6 or 8 with the double transmission. I need to get some stuff mocked and measured I suppose.

Still got to find a motor, but a SBF shouldn't be hard to source, considering a 300 I6 too if I found a good deal just to irritate people. This thing is going to be more tractor than ultra4 rig anyways.

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Are you stuck going with full width?

In the FJ40/FJ55 world, the "cool kids" use Dodge KP 60s and knock 7" off the long side. It bolts in perfectly with the stock spring setup. I've done this three times:homer: I don't think I'm screwed with turn radius and 35" tires. I could snap a picture showing how close the tire is. I know that my FJ55 has a much narrower turn radius than my stock Tacoma and S10 trucks.

If stuck with full width, why not outboard spring setup? I don't like the look but see it happen on the FJs way too often.

On to your other doubler tranny... I highly doubt you could pull that off with 95" wheel base. On my old FJ40, I did an NP203 behind a Turbo 400 and ended up with no driveline at all:
lj_predriveshaft1.jpg

Granted, that was also a big block cady(2" longer than SBC) and about 92" wheel base. However, I want to say that Turbo 400 + NP203 was basically same length as SM465 + NP203.:homer:
 
Spending a ton of time looking at old threads on the other site about doubling up transmissions, and a few about building doubler shafts. Key thing when building multi piece shafts is .003-.005" interference fit on mating components, which shouldn't be an issue for me. Gotta pull the extension housing off the NP435 to see how much the main shaft protrudes past the case, it looks as though its a considerable amount more than the SM465's that everyone uses for double transmissions. Nothing stopping me from going GM engine I suppose, although I prefer Ford.

Next couple pictures are pictures I found on the web, representing the idea I had for a body for this thing. Guy I know has a 40s IH cab thats bad enough that I wouldn't feel bad cutting up for a traditional "doodlebug" homemade tractor, although I would definitely prefer the Model A cowl/nose if I can find one. Plan would be for a simple 4 point cage, front hoop, rear hoop, with roof bars, similar to the M715 cage pictured

Last pic is of a local guy's rig "Mud Rod" that competed at TTC in 2010. I'm planning for something more crawler than mud truck, but I found it funny that I came up with the idea then remembered its been done before.

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Are you stuck going with full width?

In the FJ40/FJ55 world, the "cool kids" use Dodge KP 60s and knock 7" off the long side. It bolts in perfectly with the stock spring setup. I've done this three times:homer: I don't think I'm screwed with turn radius and 35" tires. I could snap a picture showing how close the tire is. I know that my FJ55 has a much narrower turn radius than my stock Tacoma and S10 trucks.

If stuck with full width, why not outboard spring setup? I don't like the look but see it happen on the FJs way too often.

On to your other doubler tranny... I highly doubt you could pull that off with 95" wheel base. On my old FJ40, I did an NP203 behind a Turbo 400 and ended up with no driveline at all:

Granted, that was also a big block cady(2" longer than SBC) and about 92" wheel base. However, I want to say that Turbo 400 + NP203 was basically same length as SM465 + NP203.:homer:

Yeah I know a Toyota guy that did it that way, sectioned 4" (I think)of the long side in the middle, sleeved it, vee'd out the seam and welded it back up, with a custom axle shaft. But then I'd need to match the rear with a narrow 8 lug, which a C&C 14 bolt is an option I suppose.

What's the point of tons if you're only on 35s?

If i were to go narrow track, I'd probably use the EB 44 housing I have, assemble that, and match a 8.8 up to it.

Yeah I'm nervous about the length of everything. spidr's 465/465/205 was 52.75" from bellhousing face to rear u joint face. Thats a yuuge bitch in a 95" wheelbase
 
Yeah I know a Toyota guy that did it that way, sectioned 4" (I think)of the long side in the middle, sleeved it, vee'd out the seam and welded it back up, with a custom axle shaft. But then I'd need to match the rear with a narrow 8 lug, which a C&C 14 bolt is an option I suppose.
There are two ways to do it and both are ultra simple:
Dodge D60, knock the inner C off, cut to 7" less, and beat the C back on. If not feeling froggy, take to professional welder.
Chevy D60, knock the inner C off, cut to 5" less, and beat the C back on.

I did the above 20+ years ago and again about one month ago.

For rear axle, my local axle guy charges ~$250 to shorten a side. I'm doing offset tcase so I knock 7" or so from a Ford e350 van D60 rear. Since I did and am doing chromo shafts, the "omg a new shaft" argument doesn't mean shit.:flipoff2:

What's the point of tons if you're only on 35s?
Because back when I started, no good upgrades for toyota shit and I was watching people blow up Toyota way too often. To further it, when I had the axle done, it was for a big block cady, turbo 400, np203, and 40s:homer: That project got canceled, and now the axles are under 6.0L LS full body pig(FJ55)
 
There are two ways to do it and both are ultra simple:
Dodge D60, knock the inner C off, cut to 7" less, and beat the C back on. If not feeling froggy, take to professional welder.
Chevy D60, knock the inner C off, cut to 5" less, and beat the C back on.

I did the above 20+ years ago and again about one month ago.

For rear axle, my local axle guy charges ~$250 to shorten a side. I'm doing offset tcase so I knock 7" or so from a Ford e350 van D60 rear. Since I did and am doing chromo shafts, the "omg a new shaft" argument doesn't mean shit.:flipoff2:


Because back when I started, no good upgrades for toyota shit and I was watching people blow up Toyota way too often. To further it, when I had the axle done, it was for a big block cady, turbo 400, np203, and 40s:homer: That project got canceled, and now the axles are under 6.0L LS full body pig(FJ55)

Yeah that's how we did the HP44 under my Ranger. Grind/pound the c off, cut 5" off, pound c back on, run EB long side chromo shaft so nothing custom. Cab and chassis 14 bolt is the right width to match it. I think it might be overkill for this project.

And 72Blazer, it's gonna need a lot more than triangulation :flipoff2:
 
Spending a ton of time looking at old threads on the other site about doubling up transmissions, and a few about building doubler shafts. Key thing when building multi piece shafts is .003-.005" interference fit on mating components, which shouldn't be an issue for me. Gotta pull the extension housing off the NP435 to see how much the main shaft protrudes past the case, it looks as though its a considerable amount more than the SM465's that everyone uses for double transmissions.

The 435 mainshaft necks down behind the spline (like it should). You can't just cut and re-spline to shed length. I think your best bet is to cut off the rear of the main-shaft, machine out inside the fat area where all the gears go then EDM it out so that you can stick the stock input of the next transmission into it. That should get you something suitably short without spending a ton of time fucking around adding a 31spl female input to a transmission.

The reason everyone uses the 465 for the doublers is because the input bearing is bigger making it easier to install a female input but it's not impossible with a 435 either (I'm sure you've read the build thread on TRS from the guy who was running the engine in the bed, two transmissions and two transfer cases).

I wouldn't even consider a 300 with your plans for such a long driveline.
 
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The 435 mainshaft necks down behind the spline (like it should). You can't just cut and re-spline to shed length. I think your best bet is to cut off the rear of the main-shaft, machine out inside the fat area where all the gears go then EDM it out so that you can stick the stock input of the next transmission into it. That should get you something suitably short without spending a ton of time fucking around adding a 31spl female input to a transmission.

The reason everyone uses the 465 for the doublers is because the input bearing is bigger making it easier to install a female input but it's not impossible with a 435 either (I'm sure you've read the build thread on TRS from the guy who was running the engine in the bed, two transmissions and two transfer cases).

I wouldn't even consider a 300 with your plans for such a long driveline.

If theres enough meat in the 435 mainshaft I agree with hogging it out and splining that for the 465 input. I bet the mainshaft shortened would fit in our EDM nicely. Going to play with more numbers before I rule out a 1345 doubler though

Yeah I remember the gwaii build thread, dudes a nut.
 
Judging by the pictures the rig would be open wheel / no fenders. In that case to reach your goal and keep things simple, here is an option.
Use the Ford transmission and 205 get and engine to match. Fuel Injected 300 6cyl would be sweet.
Use on of the Ford D60 fronts ( would use the KP for easier high steer ). Narrow the passenger axle tube to use a 79 Ford D60 shaft. That should get you close on the spring perch width.
Rear axle..van D60,14 bolt c&c or.....a Ford 9" narrowed to match. That would require a couple of shafts. Turn down the front 60 hubs and run 5 on 5.5" wheels.
That would not limit you from going bigger tires in the future.

BUT..I would figure out a way use the axles full width. Still would choose the KP 60 and 9" with 5x5.5" or 6x5.5" wheels.
 
If theres enough meat in the 435 mainshaft I agree with hogging it out and splining that for the 465 input. I bet the mainshaft shortened would fit in our EDM nicely. Going to play with more numbers before I rule out a 1345 doubler though

Yeah I remember the gwaii build thread, dudes a nut.

I can pull dimensions for you when I get home. I have one sitting around.
 
Doing research on the 1345/205 doubler concept, drawing inspiration from the home built 1356/205 doublers. Finding that you have to rework the shifters on the 205 since the BW range box will occupy the same space as the shift rail. Then I find this gem of a picture, 1356/205 doubler built without cutting the 1356 shaft. Seems to work because the rear output spline on the 1356 is 31 spline, which is the same as the input spline on the Ford transfer cases.
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So I researched what the output spline is on my 1345, 32 spline, same as the later GM stuff. I'd be super curious if I could mate the 1345 I have to a Chevy 205 in a similar way, which would save me from having to rework the shift rails thru the back, and saves a bit of machining.

Still researching the double transmission stuff. Does anyone have a cross section of a 1-1/8 10 spline input shaft or know the dimensions? Trying to draw some of this shit up
 
I took a 1345 apart a long time ago IIRC the splines don't match anything. I would have sworn the count was wrong but I probably wasn't thinking of using a Chevy case at the time. I did like that the oil pump was a bolt in deal and didn't just key into the soft case like damn near every case uses.

A 1-1/8 trans input is just a SAE coarse spline like you find on a PTO. It was standardized in the 1800sd so any machinist desk reference should have the tolerance specs. You get options A, B and C for tolerances. For a clutch the tolerances should be whichever one is "slip freely under no load" and for a transfer case you're going to want to use the "shit will gall together if you make it slip repeatedly" tolerances.
 
...for a transfer case you're going to want to use the "shit will gall together if you make it slip repeatedly" tolerances.

I don't seem to remember that callout in my GD&T references, must be an old version :flipoff2:
 
Still researching the double transmission stuff. Does anyone have a cross section of a 1-1/8 10 spline input shaft or know the dimensions? Trying to draw some of this shit up

What are you trying to figure out on the input shaft. I've got "bits" of one hanging in my "failed projects" bin:
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Top piece is machined SM465 input gear. The snout was cut to fit the machined NP203 output gear in the middle. The bottom is a one off duplicate of the SM465 input on the bottom end and 23 spline to fit a 23 spline NP203 input gear.
 
What are you trying to figure out on the input shaft. I've got "bits" of one hanging in my "failed projects" bin:

Top piece is machined SM465 input gear. The snout was cut to fit the machined NP203 output gear in the middle. The bottom is a one off duplicate of the SM465 input on the bottom end and 23 spline to fit a 23 spline NP203 input gear.

Trying to get the female 10 spline modeled up so I can whip out a test piece and let our EDM guy play with that before I chop a main shaft and hand him that

BTW, WTH was being planned out there?
 
Trying to get the female 10 spline modeled up so I can whip out a test piece and let our EDM guy play with that before I chop a main shaft and hand him that

BTW, WTH was being planned out there?

That was an NP203 gear reduction box in front of an SM465:eek: While it worked, the SM465 shifted like shit:laughing:
 
That was an NP203 gear reduction box in front of an SM465:eek: While it worked, the SM465 shifted like shit:laughing:

Cool concept!

The top shaft, the shortened SM465 input, is likely what I would have to copy, and bore and spline the NP435 mainshaft. Looks to be how mountainguyed67 did it, as documented at the old place

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NP435 mainshaft has a 1.990 minor OD at the gear splines and 1.670 OD where the bearing rides. You have plenty of room for a 1-1/8 input in there provided you have a +/-nothing fit in the bearing section so that it has nowhere to deform to. Length from rear of bearing area to where it necks down to smaller than 1.990 up front is ~5.5". If you go through with this I would through drill the mainshaft and plug it so you can get a punch in there and hammer out whatever is left of the input you inevitably break before deciding to go 300m.

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Priced out 5.13 gears from Summit for a 44 front and a 9" rear, came out to ~$350 without install kits. Its probably cheaper in the long run for me to not try to be a cheap fuck trying to build this double transmission deal, and just gear the axles.

I'm thinking for tire size if I can stick to 35s, I might buy a set of 35" UTV tires for 15" wheels. Keeps 1/2 tons alive and helps the theoretical gearing.

But if I don't do a doubler the 205, 1.96:1 low sucks. I could run the 1345 instead and gain a ton of gearing. I feel like I'll likely still build a doubler.

Stupid thought thats crossed my mind. While parts hunting I've found a Chevy 250 straight 6 for right money that I'll likely buy for another project, but considering using it in this, with the chevy 465 I was supposed to get for the double transmission deal, guy also has a 203 he was going to junk. Might change to Chevy drivetrain. Not sure yet just rattling off options.
 
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