No two engines could possibly be more opposite. The diesel swap would be high on my list for a daily driver (for economy reasons), for a trail or rock rig. The reliabilty is also much better than a rotary, I would imagine.
The diesel is a low rpm, torque engine. The rotary is exactly the opposite. I mean, it has alot more torque than a Suzuki 1.3, but compared to a diesel it must be revved alot more.
That brings us to the rotary, and why I prefer it. It is a high RPM, high horsepower screamer. I play in the sand, see, where torque is not the answer. In sand you need RPM and power. The rotary is perfect here. It is also very good at mud for the same reasons.
If you want wheel speed, go rotary. If you want crawling, and trail power, go diesel.
Also, there is no kit for a rotary swap. Mine is all home fabricated. I even shortened the RX7 transmission. [img]/ubbthreads/images/graemlins/shocked.gif[/img]
Around 170HP is quite fun in a Samurai, but it's alot more work than the deisel. Higher mantainance, too.
Here is link to my web page, look around a bit. You'll see some of what it took.