N14 reversion to computer less 855

I know of one Frankencummins like you describe. Family's been working on Cummins motors since the days of 220's and an iron lung 262. Can't remember what their combination was was pretty stout.

 

Big Cam Cummins heads will fit on the N14, but you will have a valve to piston problem. I think @jamespmack may remember me building a fully mechanical Frankenstein of this type.

It’s not all just bolt it on and go as mentioned earlier…..

 

Heads aren’t really the issue, it’s cam timing and the rockers, if wanting to stay with N14 mechanical parts.

Honestly no matter what it’s never going to be cheaper than fixing the issues with the electronic engine.