Best engine choice for swap into '84 BII...

[APF1984BII]

I just discovered that the 2.8 in my 1984 has a leaking (probably burned) exhaust valve in the #5 cylinder. Just taking care of that is going to breathe fresh life into the little engine, but it won't be the end of the line for it or for the truck. While I will be swapping fuel injection onto the factory engine, I will be looking to replace it with something else. The overall question is, what is the best engine/powertrain choice for this swap? The criteria for judgment are ease of completing the swap, reliability, off-road and on-road durability and towing potential. If it can be done, I would like to see a 5-speed manual transmission in the tunnel, although I could be okay with a 4-speed automatic. Also, if possible, I would like to keep the transfer case lever sticking through the floor, and have it be functional. Thoughts? As always, all input is appreciated. Thanks in advance - Chris

 

[DirtBronco]

Keep the 2.8! Slap on a good cam and duraspark it. Stock cam timing with a 390/410 lift would give you a significant improvement across the entire power band. An engine overhaul and transmission swap can be done for the same or less than swapping in something else, which can be limiting depending on your technical skill.

If you do want a swap:
A V8 needs new front suspension for the added weight, custom engine mounts, and a whole bunch of junkyard runs for new drivetrain bits.
A 4.0 OHV swap is "easy", as it is heavily documented at this point. You need to pull it and all the electronics off a 1st gen explorer or 1.5 gen ranger.
If you wanna get wild, throw in VM425 or 4BT, but that's a lot of financial investment in beer and Tylenol-migraine alone.

Contrary to what a lot of people will spout, the small displacement cologne's are very good engines and can be made into rev monsters with very little effort. Kick out the cam duration and stock internals will bounce off 7k.

If you want to go with a manual, get a Mazda M5OD and a BW1356 t-case. Auto->manual swap are commonly documented, and they are out there and the combo is not that hard to find.

 

[APF1984BII]

Thanks, Dirt! Your advice is encouraging. I had just about resigned myself to a 4.0 swap with an A4OD chaser. Keeping the 2.8 and building it a little has a great deal more appeal. I would like an auto trans with one more gear, though - are there such a transmission that just slips right in between the 2.8 and the factory t-case?

 

[DirtBronco]

Ford made a 5 speed auto, the 5R55e, for the second half of the Mazda-Ranger production. No idea as to its compatibility with the rest of the driveline on older RBV’s tho. I doubt it would be a simple swap but there’s definitely potential to it.

Final drive is .75, as opposed to the M5OD’s .79, so highway economy and top speed would see gains.