I've read that the 'L Series' diesel was developed from the Perkins Prima & that, in turn, was based on older British Leyland designs. The L Series was the initial diesel engine fitted to Freelanders & was also in lots of Rover cars (and even MG Zx's up to 2005 ish) so its both newer and should be more available.
Despite the obvious 'drama' below (clutch slave went then but I have had to fit a s/h injector pump), the one fitted to my Freelander still runs well approaching 200,000 miles:
Power and torque wise it offers a slight improvement on the older Prima I presume Freelander versions have had the normal Land Rover "improvements to water/mud resistance and low-down torque"?
So...
With its connections to the Prima, does an L Series make a relatively 'easy' transplant onto any RWD gearbox?
A few years back, I bought an old seized V8 (for a coffee table project!) off a guy on eBay. The chap told me he was working on fitting an L Series engine into a LWB Series 2/3 Landy but he didn't explain how & I've not seen any proof of its existence since.
I also found the (now sadly defunct) "Pimp My Sherpa" website!
A guy on there had a thread covering the transplant of an L-Series engine to an LT-77 in an old Sherpa van (click on "L-Series Conversion" if the website ever re-appears)
I think he made his own conversion plate but there's no way to check at the moment
To add to the 'attractiveness' of the L Series, it seems people have discovered ways to boost their outputs!
Again the link I had is now dead but luckily I had lifted from some chat from the Practical Performance Car forums (link was: www.ppcmag.co.uk/forum/viewtopic.php?f=39&t=9796#p99682)
Standard turbo is good for about 150Bhp, for bit of work, you can make a GT2256v turbo fit (VNT, boost can start at about 1700rpm, and with massive amounts of top-end flow!) A non-freelander style exhaust manifold is needed to stop the bigger turbo blowing the head off from excessive exhaust manifold pressure (EMP - a big issue on tuned dervs) and then it's just an extension bolted onto that, to relocate the turbo.
The stock pump + injectors will flow upto around 160Bhp - at this point you need to swap the injector nozzles to Freelander {sic} 300TDi items, to get yourself well over 200Bhp, and in excess of 350lb/ft of torque....
NB "Freelander 300Tdi" was obviously a typo but which bit? Having checked, apparently it has been found that the Tdi injector nozzles (as stated!) swap over onto the L Series injectors & boost fuelling.
Can anyone provide me with any more info?