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44 Posts
Discussion Starter #1
I have a 79 bronco that I want to put a diesel into. I have not made up my mind on a 6bt or 4bt yet.
It seems like a 6bt is easier to get and I can get an installation kit and instruction book from, but that motor weighs alot more and might more easily tear up my axles.

The 4bt will provide all the power I need, and better mileage than the 6bt. The bad thing is it will probably require more custom work and fit up than the 6bt and they seem harder to find.

Either way, I will be getting the swap done, so I want to plan as much ahead of time as possible. If you have completed or almost done with your swap please provide some input.

Is the swap worth it?
What is the performance you are getting and what is your set up?
How much did the total swap cost you?
What was the hardest part of the swap?
What would you differently?
If you have a 4bt please provide the serial number.
Basically if tell me anything you wish you would have known before starting the project.

Thanks to all of you in advance.

My dad bought this bronco when I was five. I had to wash it every saturday before church the next day.
He gave it to me at 15 and I have had it ever since. I drove it every day until 2006. After college gas was almost 4 bucks and I needed a more commuter friendly car. Now that I am almost 30 I want to revive the old bronco and take care of it and restore.
I will add some pics after I reach my 10 post requirement before posting links

Again thanks in advance, I really appreciate it

299 Posts

My 79 F-150 build is in my sign link.

I would save your money and not buy the fordcummins book. I will give you all my information for FREE, well for the 4bt and hydroboost.

I know I have as much or more power than the warmed up 351M that I was running. I just changed out the engine.

We will need more information on what you are planning on doing with the Bronco....

My swap was more than worth it.

I don't know performance numbers, but butt numbers are better than before with more to come from-fuel pin, turbo, piston lift pump, and more tuning, along with a 5 speed conversion.

I would plan on $6K and that should do almost everything. Some will get it done for less and some will take more. Depends on what you can do, how well you can find parts and how lucky you are.

The hardest part was finding time with a new baby to do the project. (I removed the front clip to install my engine)

I would do a few things differently-when I had my injectors rebuild, I would have had them modifiec to 50+ or 70+, moved my IC down, maybe a new radiator or at least a shorter one, maybe even install the 5-speed at the same time, also might have went with the lord isolators instead of the dodge pucks.

Thoughts about using a 6bt. It can be and has been done. I would avoid it in a bronce since they are already nose heavy. Unless you cut the firewall out to move the engine back 6" or more to move the center of gravity, you will add to the nose heavy feel. Add in a winch bumper, bigger tires and you will increase the nose heavy feel even more. The dana 44 will hold up to the cummins with normal tires and driving style. You might have to replace the ball joints and wheel bearings more often. (they sell upgraded ball joints for the 44).

That being said, I'm going to install a 6bt, 47re, t-case, in my 77 crew cab with a dana 44hd (unless I can find a cheap dana 60). I will not be offroading or installing large tires. This will be a traveling truck for my enjoyment. 6bt since it's quiter and I have a long wheel base truck. The dana 44 holds up to 44in mud boggers with 460's and winches all day long. You just have to build them right.

PM me if you have some other questions.

216 Posts
One of my students and I are putting a 6bt in a 76 F250 High Boy now! I found an engine pretty much complete for $500 out of a 2wd out of a 1989 dodge 250. He had to put about $650 in a rering kit and Valve Job. I made his motor mounts and were are using the Getrag 360 2WD tranny to hook up to the divorced 205 T-Case. We Changed out the D60 with 4 10 in the rear to a The D70 3 54 that came out of the Dodge. I had a D44 with 3 54 gears out of a 3/4 Dodge that went up front. He also has about $350 in Rebuilt injectors. The old ones had over 300K on them and the injector pump just got rebuuilt about a year ago!
So thanks for letin me HI Jack your thread for a minute! I'll post a build up thread when we start gettin things closer together!

Good luck with yours.

My students and I will be watchin this one!
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