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Discussion Starter #1
Hello everyone. I'm not really a member of this forum but I have occasionally browsed here looking for information and you guys are awesome. I stopped by to visit your classifieds and thought I may as well leave a link to my build while here in case anyone was interested (reading the stickies I'm under the impression this is fine, if I'm violating any rules feel free to remove my post).

I'm in the middle of a pretty silly swap, a 12 valve first gen ford explorer. I promise it isn't as hair brained as it sounds haha, there IS a plan. At the time of posting this I currently have a donor ram 2500 (12 valve p-pump 2wd auto), 2 donor explorers (91-94 generation), and a nv4500. Still lacking a transfer case, bell housing, and other various assorted transmission parts. I have test fit the 12 valve in the explorer, then removed the body from the frame and I am starting to work on getting the drivetrain setup on a rolling chassis. I will try to respond to any questions/comments here but the place I spend most my time is on explorerforum and youtube. Hopefully this is a build you guys are interested in!

As a teaser here's a picture of the 6BT test fit in the explorer. Note it isn't sitting in exactly the right place yet, should be about 4" lower and 2" further back but a combination of a bracket for the front TTB and the body which still needs clearencing was blocking the oil pan from sitting down in the car properly. However all things considered (even if it doesn't look it from the picture), this test fit showed me it will fit between the frame rails and under the hood. The biggest issue will be the length of course, but between clearencing/cutting the firewall and possibly moving the radiator further up I should get that to work as well. Either way I'm committed to this project and we'll see what it ends up taking to make it work!
129866


The full build thread is here:

and it is in Vlog format on youtube here:
 

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For simplicity you could try to find a rusted out 1st gen Cummins Dodge in your area with 3.07 gearing. They came with Dana 61 and 71 F&R axles. Most don't want them due to the high speed gearing but for a light weight explorer they would be awesome with a 6BT. those with a set of Hummer H1 or late model GM or Dodge factory rims wouldnt be much wider than a set of 10" wide wheels on your Explorer axles for stick out! Otherwise for pricing its hard to beat a set of 3.55 take outs from a Ford Super Duty F250. Get one after 2002 to. be sure you get a Dana 60 front axle. I wouldn't suggest the Dana 35 or 44 due to the weight and tq of the 6BT. It can easily break shafts/joints if you get it in a bind. The Dana 50 would probably be ok but if you are having to do a swap anyway, why......?
 

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Don't forget you have an intercooler to stuff in there along with a big radiator. Lot of engine to put in an Explorer but stranger things have been done. It was mentioned to look for the 3.07 gear axles. Those have become super rare. They only came on the very first of the 6bt Dodges with the TF727 transmission. And those axles are a Dana 61 front and a Dana 70U or 70B. There is no such axle as a Dana 71 rear .
 

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He doesn't need heavy axles under an exploder. Nor does it need an intercooler or bigger radiator.

I'm sure it will cool fine if he can get it to fit. Front springs would be where I would not know what to use for the application. If you run across one, an early bronco 44 front and radius arms would be ideal.
 

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Discussion Starter #5
Thank you for all your input everyone!

For simplicity you could try to find a rusted out 1st gen Cummins Dodge in your area with 3.07 gearing. The Dana 50 would probably be ok but if you are having to do a swap anyway, why......?
That would be nice! However the optimal setup I'm looking at right now would be using the rear dana 70 that came in my parts truck. It already has 3.54/3.55 and that gear ratio is readily available in my front gearing options as well. With 3.54's and 33" tires I could run down the highway at 80 at about 2k RPM's which should be pretty decent. Most would say "why....?" to this whole build so get ready to say it again but I'd like to keep TTB in the front. If this build were more oriented towards rock crawling or anything like that then it would be solid axle swap no question, however I'm actually a fan of TTB (rarely hear that I'm sure haha). Optimal front for me would most likely be the dana 50 but on coils instead of leafs as this would give me 8 lugs to match the rear and be the stronger setup. However the driver side member on the TTB dana 44 is longer so another option could be dana 44 with the GMC outters swap to get 8 lugs, this option would be weaker but likely have more potential for flex. I'm leaning towards the dana 50. The TTB dana 50 came in f250 powerstrokes and the like and this build will be MUCH lighter then that, so I don't think strength will be an issue if I go this route. All this can be had for <$200 at my local U-pull (noone wants these TTB setups haha).

Don't forget you have an intercooler to stuff in there along with a big radiator. Lot of engine to put in an Explorer but stranger things have been done. It was mentioned to look for the 3.07 gear axles. Those have become super rare. They only came on the very first of the 6bt Dodges with the TF727 transmission. And those axles are a Dana 61 front and a Dana 70U or 70B. There is no such axle as a Dana 71 rear .
I think 3.54's with 33's would be the ultimate goal (see above). But it is cool to know about those 3.07 axles. I agree that I probably don't "need" the cummins rad and such, however the way it's setup on the ram the intercooler radiator and evaporator are all bolted to the stock radiator support in a very nice package and my optimal setup would be to use the ram rad support everything included. The obvious issues are that it adds even more length under the hood, and unlike the stock rad setup which fits between the headlights the headlights would be in the way here. This would take some body work for sure likely including some custom lengthened fenders and hood. The much easier alternative would be to use the explorer rad and either forgo the intercooler or stuff it underneath (not really a fan of that option).

He doesn't need heavy axles under an exploder. Nor does it need an intercooler or bigger radiator.

I'm sure it will cool fine if he can get it to fit. Front springs would be where I would not know what to use for the application. If you run across one, an early bronco 44 front and radius arms would be ideal.
I've been looking through my local junkyards and they have plenty of dana 44 TTB (bronco and f150) and dana 50 TTB options (van and f250). I think I'm leaning towards coil swapping a dana 50 setup but a dana 44 setup is still on the table. As for springs my tentative plan would be to swap the coil buckets from my explorer and reuse some aftermarket lift springs that I have, they were MUCH too stiff for an explorer. However if they endup still being nowhere near stiff enough I will start looking into different f150/f250 spring options or even try and find some stiffer aftermarket options. I do need to do some more research on the springs themselves for sure!

Thanks again for everyone's input! Remember there's also the full build thread linked above if you want all the excruciating detail haha.
 

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Not sure you'll get by with the stock radiator with a P pump. Stock radiators are usually more than adequate for a 4bt but the 6bt is 50% bigger and make more heat. If you're just going to be cruising around and no turning up the power then it might be OK. That engine was designed for an intercooler. Eliminating it will lower power output. Hot air to the intake makes poor power. You can have air temp coming off the turbo in the 300 deg + range. That's why those hose boots are silicone rubber. Not sure how you'd covert the Dana 50 to coil springs. As far as I know all of them were leaf springs. I own one. All the late model Fords are coil springs but their wheel bolt pattern wouldn't match the Dodge.
 

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Not sure you'll get by with the stock radiator with a P pump. Stock radiators are usually more than adequate for a 4bt but the 6bt is 50% bigger and make more heat. If you're just going to be cruising around and no turning up the power then it might be OK. That engine was designed for an intercooler. Eliminating it will lower power output. Hot air to the intake makes poor power. You can have air temp coming off the turbo in the 300 deg + range. That's why those hose boots are silicone rubber. Not sure how you'd covert the Dana 50 to coil springs. As far as I know all of them were leaf springs. I own one. All the late model Fords are coil springs but their wheel bolt pattern wouldn't match the Dodge.
It isn't that big of a deal. You can tell when intake temps are getting up there on hot days when it just doesn't make the power.

Intercooler is great and all, but there are applications where the installation just isn't going to be clean or efficient and that is where you forgo the IC and see how it does. There's always water-meth.
 

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There is no such axle as a Dana 71 rear .
Supposedly the 71 has a different pinion offset (~1/4")
in the housing to allow for the "unconventional" gear dimensions. They use the same carrier as standard 70 though IIRC. They have become pretty rare though as people didn't want them for typical builds due to not being able to easliy re-gear them with standard 70 sets. Again IIRC there were ring gear spacers at one point available but I don't know about now as the axles haven't been produced in roughly 3 decades.
 

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How about a water to air IC? Might be a compact way to cool the charge air. And you can mount the radiator elsewhere on the vehicle. Or you could just use the primary radiator to supply water to the IC.
 

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Not sure you'll get by with the stock radiator with a P pump. Stock radiators are usually more than adequate for a 4bt but the 6bt is 50% bigger and make more heat. If you're just going to be cruising around and no turning up the power then it might be OK. That engine was designed for an intercooler. Eliminating it will lower power output. Hot air to the intake makes poor power. You can have air temp coming off the turbo in the 300 deg + range. That's why those hose boots are silicone rubber. Not sure how you'd covert the Dana 50 to coil springs. As far as I know all of them were leaf springs. I own one. All the late model Fords are coil springs but their wheel bolt pattern wouldn't match the Dodge.
My thinking is I have the intercooler so I might as well use it ;) . My preferred setup would be the stock ram rad support WITH intercooler, ram rad, and evaporator, but I didn't want to totally ignore the possibility of doing it another (easier) way. As for converting a dana 50 to coils the fabrication involved should be coil buckets, pivots, and radius arms. IMO likely easier then doing a solid axle swap on coils especially if the solid axle swap involved a 4 link. Also someone on the other forum mentioned someone makes a kit for doing this, but its outrageously expensive. Gives an idea of what it would take but I would fab up the parts myself. In fact, now that I think about it if they sell the coils that come with that kit separately it may be just the ticket for my build if I can't find heavy duty springs anywhere else...
Stage 1 Dana 50 TTB Front Leaf Spring Delete Kit / F250 & F350 | Solo Motorsports

How about a water to air IC? Might be a compact way to cool the charge air. And you can mount the radiator elsewhere on the vehicle. Or you could just use the primary radiator to supply water to the IC.
Clever thinking haha. I think using the stock intercooler really is the best way to go. I set off with this build planning on having to do custom lengthened fenders and hood and if that's what I have to do to make room for the ram parts so be it. However I really am trying to focus on getting the engine setup in the chassis at the moment and then I'll concentrate on what body mods and fitting of the intercooler/rad and everything after that's done (best laid plans change if I have to change the position of the drivetrain and all haha).
 
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