In reply to L5wolvesf :
I'm thinking about a variety of options. I will probably use it as-is for a while, but it is fun to think about swaps. SBC has been the go-to swap in America for decades, but I'd like to keep it Toyota, because I'm a nerd like that. I'm open to suggestions.
What do I like about the current Toyota 3B with turbo?
Simple, easy enough to work on, good fuel economy, plenty of room in the engine bay, and engine weight is behind the front axle. It is also really amazing just off idle...it pulls from 650rpm, no worries about bogging/stalling, and the hand throttle (hand accelerator?) is great for crawling.
What do I dislike? Terrible NVH; general diesel clattering, and stuff shakes and vibrates, plus there is a nasty harmonic at around 1600rpm that makes it worse in that rev range. Stinky diesel smell. My garage is the ground floor of my house, and I am planning to push it outside to start it up because the startup smoke cloud doesn't smell great. Lack of grunt for highway use. Difficulty cooling on uphills at highway speed. The relatively narrow rev range adds an interesting driving challenge, but something that winds out to more than 3500-4000rpm would be nice. Parts availability; I think these engines date back to the late-60's or early-70's, and were supplanted with newer designs a couple years after my 1986 was built. Lack of A/C. Toyota stuff is NLA. There is a reportedly good quality aftermarket kit. The kit is $4000 for the parts, still needs to be installed and charged. 😩
Considerations:
Keeping it mechanically-injected diesel simplifies quite a few things. If I stay mechanical injection turbo diesel I can reuse tank/filler/fuel lines, and leave the 24V electrical system intact. But this also poses some challenges if I want to keep it Toyota, because more grunt means a straight six like a 1HZ or 1HD-FT, which presents challenges mating to the transmission (needs bellhousing, input shaft, shifter, and trans crossmember changed, but same box), and adds weight, and weight further forward. The best of these engines are also not cheap because every Cruiserhead wants one.
If I jump ahead a generation of turbo diesels, there is a performance jump, but these have multivalve heads and direct injection controlled by EFI, which adds quite a bit to the list of stuff needing to be swapped, and they are still heavy and are really expensive. Like $15K used expensive.
If I convert to gas, the options open up, and I think a 1UZ Toyota/Lexus V-8 would be really sweet. It wouldn't be much harder than swapping to a modern diesel like a 1HD-FTE or 1KD-FTV. There are a couple big hurdles here: connecting to the transmission, and converting to 12V. For the transmission I can chase down little parts like throwout bearing, clutch slave, clutch disk, etc, and try to pin down some Australian specialist who supposedly made/makes one but doesn't list on their site to maybe make me a bellhousing to mate to my existing H55, or I need to find the right H151/H152 transmission that was only sold for a couple years, and only in the Middle East market. The gas V-8 will have a 12V alternator and ECU/sensors/injectors/starter wanting 12V. If I convert the truck, I believe I will need to swap all the lights, gauges, maybe some wiring?...not really sure TBH.
Anybody on here ever done a 24V->12V conversion and can offer insight?
The pluses include a much lighter engine that is still short, rev-happy, could support A/C, less noise, clatter, and emissions, and hopefully reasonably efficient.
A lot to think about...
