I'm looking at re-powering a 406 Unimog, not sure which engine to use.

It has to be M-B diesel.

I know that all of the earlier engines are mechanically injected and can easily be turned up to obscene levels, I'm thinking that the 603 is a nice engine and fairly easy to find. What engine would others suggest considering that this truck uses a significant amount of power and RPM to cruise at 70mph or accelerate? Which engine is the best balance of reliable and powerful for truck use?

It'll mostly get around-town use but will be intended for some off-road and some heavy hauling.

- Jeff
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