American Thunder
New member
My 1978 Bronco project truck, that I picked up for only a few hundred bucks about 3 months ago. No motor, trans, but I have the original NP205 case. The truck has 86,000 miles on it, so the case is likely in great shape inside.
The previous owner sandblasted the entire underside of the body and the chassis, and sprayed it with DP90 epoxy primer. It'll need some floor work eventually, as it's thin, and I plan on full quarter replacement on both sides next year. But the truck is in very good, solid condition.
The entire 6" skyjacker suspension is new, poly bushings and all.
As for a motor, I'm going to swap in a 6BT Cummins. I picked up a Cummins powered 1991 Dodge 3/4 ton dump truck with 159,000 miles on it for $1300. I already have the transmission sold, the Dana 70 is up for sale, and I will scrap out the rest of it. The Cummins motor will end up costing me about $400 when all is said and done.
This thing runs like the day it was built. Not even a puff of smoke when starting it cold, it's an awesome motor. Looks a little rough now, but I'll spray it either Ford corporate dark blue or the lighter Cummins blue, undecided so far.
I'm buying an adapter to bolt the Cummins up to my C6 transmission, an adapter to bolt the Ford torque converter to the Cummins flexplate, and a set of motor mounts made for the swap. Of course I'm using the NP205 behind the C6. A buddy of mine owns a trans shop, so he's going to toughen and freshen the C6 for me, and I'll probably use a C6 torque converter from a 6.9/7.3 application. I removed the stock throttle pedal with the linkage, and took the pedal from the dodge parts truck to see if it would fit. I had to drill one hole in the firewall and enlarge another hole where the cable plugs in, otherwise the '91 dodge pedal and cable is a direct swap into the '78 Bronc. It took about 5 minutes.
I'm installing a floor shifter and cable, though not sure which model yet. I already upgraded the brake master and booster with new F350 parts, and the rear wheel cylinders are now F350 parts, too. Only thing left for the brakes is upgrading the front calipers and possibly installing vented rotors.
The motor mounts that Fordcummins.com sells move the engine back 3", almost touching the firewall,(the 3" body lift helps here) which means I can probably use the stock length rear driveshaft with my 6" suspension lift, as the trans/case are also moved rearward 3". This will help quite a bit in getting some of the 975 lbs of turbodiesel engine weight off the nose of the truck. Eventually, I'll order up a lightweight glass hood for it, too. Between those 2 things, the front axle should have about the same weight on it as it does with a 460 swap. I'm going to install a quad shock setup also. I may also build an aluminum front bumper to save more weight.
For exhaust, I'm running a 4" downpipe into 4" exhaust with no muffler, a single 90 degree bend, and it'll exit under the passenger door.
I made a short video clip of the 6BT Cummins running. I removed the muffler so I'd get an idea what it will sound like in the Bronco.
http://s4.photobucket.com/albums/y149/amer...ns59stock-1.flv
When it's done, it will have 3.50 gears, 35" tires, 3 speed C6 auto, with the motor making 300 hp at 2800 rpm and 600 ft/lbs at 1800 rpm. It'll cruise at 2000 rpm at 55 mph. I may swap in a set of 3.00 gears or even 2.73s, depending on how the motor feels, to get better mileage, as this will be my daily driver, and I doubt the motor will need much gearing to easily move the Bronco.
Some guys at Cummins agreed with my guesstimation of mid to high 20 mpg, we'll see.
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