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Discussion Starter #1
Hello im new here. I have a 1993 dodge dakota ext cab 4x4 with 3 inch suspension lift. Has 3.55 gears. The trans just took a crap on me and we have a local diesel shop that ill be working with to put a 4bt/47rh into the truck. Im wanting to build it but I wanna do it from a different stand point. It will be my daily driver so I wanna build the motor for mpg and reliabilty and just gain power as a side effect. I basically just want the motor to run as effiecently and healthy as possible. How would you guys build it? Please give a little more detail than u normally would as Im just getting started learning about diesels. Thanks so much.
 

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Check out the FAQs and stickies. Lots of info on here. Takes alot of homework. Your performance mods will depend on which 4bt and turbo you have. Which injection pump you have. Stuff like that. You want to stick with a smaller turbo for reliability and efficiency. You should run your gear ratios, and your tranny ratios on an online gear ratio calculator to see if you will be happy with your rpms vs mph.
 

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Im wanting to build it but I wanna do it from a different stand point. .

REALLY??! breaking new ground there huh? 99% of the swaps here are done for that reason. Pick a Dakota swap and copy it! The 47RH is a mechanical tranny so easy-peasy. Getting the 4BT to fit around a 4x4 Dakota's suspension is the trick. Its been done numerous times, so you have plenty of pictures and written detailed how-to's to guide you.
The important details are how will you use the Dakota? Daily driver means nothing if you are an avid bass fisher who will be towing a 20' bass boat every other weekend! or a 25' travel trailer during the summer. You have to build EVERYTHING to work together, and then drive it appropriately to how you built it!.
 

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Discussion Starter #4
What I meant was I wasnt looking for any huge power gains. The motor I will be running will probably be ve pumped
 

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What I meant was I wasnt looking for any huge power gains. The motor I will be running will probably be ve pumped
Im wanting to build it but I wanna do it from a different stand point. It will be my daily driver so I wanna build the motor for mpg and reliabilty and just gain power as a side effect.

And what I meant was you are looking for the exact same thing the large majority here are doing/did their swap for. This site is populated primarily by folks who diesel swaps for the reason diesels are used in the commercial realm. economy, longevity, torque, and reliability. Thi isn't like the majority of other diesel sites out there who are supporting the diesel go fast crowd by plopping absurdly large turbos and injectors on their daily drivers because they saw it on High hp magazine rigs. We've also got guys who've built monster hp race grade Dakotas. So unfortunately to do something "different" with a Dakota you'd need to build a monster car crusher, diesel electric hybrid, LPG powered or something truly different. Otherwise you are lucky and the pathway has already been laid out for you. Regardless though the difficult parts of most any swap-fitting the driveline and figuring out how to get everything to play nice-has been accomplished with 1st and 2nd gen Dakotas.
I'm just screwing with ya. I truly wish you were doing something NEW. I also hope YOU are doing it so it will be better documented and photographed. That is what this site is about, not necessarily telling that you had a shop put together a truck for you that you can't really answer any of the technical questions others looking to build a similar vehicle may have. No 2 truly custom builds are ever the same and it is those differences that others following behind you may wish to duplicate. Bolting a 47RH to a 4BT is common place and for good reason. Its reliable and simple, a great match to a mechanical 4BT! However you may use a Chrysler 300M shifter or something equally "different", and that will be what piques someone's interest.
 

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Discussion Starter #6
Thanks for the support twisted. Im glad others have done it before because me tryin to accomplish it without having examples to look at wouldnt be pretty. Im a heavy equipment iperator and truck driver and as much as I love diesels and muscle cars and well basically anything with a motor. Im not the greatest fabricator. I guess im an ok mechanic on gas motors but i just dont know much about diesels. The shop that will be installing it knows alot tho and I made it part of the deal that if they did the install than I would be there every step of the way and they would teach me all about it.
 

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Good for you. If you have a truly good rapport with the mechanic doing the work, ask "Why", everytime he does something you don't fully understand. By that I mean if you "think" you know why, remove all doubt and ask-Why. Very little transfers over from gas tech to diesels when tuning. The diesel to gasser relationship regarding combustion chamber temps and air:fuel ratios is 100% reversed up to a point!
 

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Efficiency is what diesels are all about. There are some mods that can help and gain power without sacrificing economy. First, remove the injectors and have them pop tested and pressure matched. Injectors firing identically make for a cleaner burn, smoother running, and better mileage. Second, I'd change the turbo to either a HX30W or HE221W. Much better turbo design for these engines and will make more efficient use of the spent exhaust gases. Third, in relation to the turbo I'd do a minor exhaust port matching on the head. Just cleaning it up a bit and getting the ports aligned to the gasket will help with turbo spool. Not a real big thing but every little bit helps. In conjunction with those two items, you might consider a cut down CR exhaust manifold. The round ports can be reshaped to work with the rectangular port head and those flow much better. Next, add an intercooler. Cool air makes more power. Make sure you have g good free flowing air cleaner. Try to get it where it draws air from a cool area. Of course, then there's the IP. You can tinker with timing and fuel settings until you find the magic match. Although most don't do this, but another mod would be a new cam grind. Something like a Colt Stage 2 which isn't too radical. All this is assuming the engine isn't flat worn out.
 

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Here's a different standpoint.
Have they given you an estimate on what it will cost? A new 4bt will cost upwards of $5k, used about half that. At a typical shop rate of $75/hour, you will be into this swap for upwards of $10k in a truck that's not worth $5k.
Most of us do the swap ourselves, because of the cost of having a shop do it.
My 2wd '81 gets about 30mpg, a 4wd will get less.
Might be better to repair the trans and trade it in on one of the new Ram diesel 1500's which are expected to get high 20's mpg's, or one of the imports.
Costwise, diesel is $.60 per gallon more than gas now, so a newer midsize gas p/u would probably be more cost effective.
 

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I dont think anyone here looks at resale or trade in vs total cost. Any one doing swap has to know up front what the costs can run into and the scale is usually tipped to the point of your wallet being emptied quickly. We have close to 17k into a midwest 3/4 ton chevy but its fun and knocks down good mpg's. Any 3/4 ton chevy normally goes for about 1500 bucks and a dakota is no different. I would recommend finding a 4bt swap done close and going for a ride to find out if you can stand driving one. They are obnoxious loud and have just enough power to get out of their own way stock. With tweaks they improve. If anyone can get the swap done for less than 10k without it being a total pile I would like to see it. And you thought boating was expensive..
 

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I dont think anyone here looks at resale or trade in vs total cost. Any one doing swap has to know up front what the costs can run into and the scale is usually tipped to the point of your wallet being emptied quickly. We have close to 17k into a midwest 3/4 ton chevy but its fun and knocks down good mpg's. Any 3/4 ton chevy normally goes for about 1500 bucks and a dakota is no different. I would recommend finding a 4bt swap done close and going for a ride to find out if you can stand driving one. They are obnoxious loud and have just enough power to get out of their own way stock. With tweaks they improve. If anyone can get the swap done for less than 10k without it being a total pile I would like to see it. And you thought boating was expensive..
^^^^All this plus one more thing to consider.

When you see a 4BT swap listed for sale you may think it expensive. Those of us doing or having done one would quickly tell you that most of the time the person is just looking to get most of their money for parts back. If you can find one close to done that is along the lines of what you seek you may really want to give it a hard look. It very well may save you a ton of time spent scrounging parts and depending, they may have gotten a much better price on things than you could!
 
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