The guy who runs a 600 hp Cummins in his 96 (?) and gets 20+ mpg town highway mix will tell you: diesel.
One of the guys on the Centurion website I hang out on, did a 400,000 mile breakdown, and came up with a 8 mpg 460 being cheaper over the life of the vehicle.
I would say diesel.
Go to Oilburners, and ask that.
Go to 4bt swap and ask that.
Handful of people here that have dieseled there bronco's, I being one of them. and they are sold.
Hard to make a car that burns reg. unleaded use alternative energy sources.
Diesel is easy. Pour it in the tank. There may be some hoops to jump through to get it there.... but pour it in the tank.
other questions, how mechanical are you?
can you do the swap? or are you still figuring out Blinker fluid is a myth?
If you can't do the swap, it can be expensive to run.
Does your area smog test? if so.... odds are a 1995 Diesel won't be tested, but a 1995 Bronco will be. Figure out the red tape there.
Against Federal law to install a motor older than 1995 in that rig, so your options for mechanical diesel, are Cummins 4 or 6 cylinder, Isuzu 4 or 6 cylinder, or well thats about it.
Why mechanical? less wiring, either of the above motors are a 1 wire system, wire the alt, the gauges, the starting system, and then a hot lead to the IP, about that basic. A PSD is a whole harness like an EFI gasser rig.
Are you gonna want an Auto? E4oD's are spendy, and the adapter plate is spendy as well.
You can run whatever, but should they get too curious, best to have yer ducks in a row.
How are you going to use it?
High rpm driving style? Or low?
High rpm driving style DOES NOT apply unless you stick some cash in it.. some of those Cumstain guys are spinning big block gas rpm's out of there straight 6. My IDI caps at 32.. if I pull the governor plate, I can squeeze a safe4k, but I am going to be tall enough geared, 32 is fine.
Gotta love the cummins 6bt. I went back and forth between that and a 460 for the longest time....ended up going 460. Reasons were cost and weight. I just wasnt confident in putting that much weight in front of a vehicle with such a short wheelbase and with my soft suspension. Cost is pretty self explanatory. I still want one though....probably end up buying a used 2nd Gen 2500 to assume the duties of DD/tow rig.
Might be a tight squeeze, but an IH DT466 is a way better engine than a B series Cummins. The old mech style are not hard to find. CAT 3116 is another good engine for a small rig, but I think they're all electronic. For a transmission, an Allison MT series will hold up.
tight squeeze? no. Do a search.. a DT466 is a HUGE change, we are talking body lifts, like 6" , fabbing in a dog house etc. a DT360, is more motor than a cummins, and a better fit, only an inch each way bigger than a 6bt, and capable of stupid horsepower. Jump on to PowerStroke Nation, and do a search for DT360 Pipewhiner has done way to hi 02 StupidDuty, it is pretty sweet.
the Ford401 is a good choice as well, although larger than a 6bt, 40" front of accessories, to back of Block.