Hi Mike ,
First off , congratulations for owning one the most useful and practical of all Series Ones , namely a long wheel base , hopefully a 107” . I have read through the other replies to your question and there is some useful advice to be found in them , so I thought I would add my contribution . First off , I would go along to here
http://www.lrsoc.com/forum/index.php and search out all the TDI conversions that have been discussed there . Like here , you will find those people who think doing anything to a Series One that wasn’t done when they were made , sacrilegious and will devalue them and should be punishable by death , blah blah blah . Pay them no heed , as has been said it is your Land Rover to do what you wish with . In particular search out Dale Radford’s 300 TDI conversion into his 107” station wagon . He spent a lot of time and effort into that restoration , but he is a clever and talented chap .
Search out on YouTube Steven Patchett’s Team Faff videos of his various trips with his mates around Europe and the UK in his 200Tdi powered 80” . Very inspiring , and well put together videos . Here’s one to get you started
Three more websites ( if you are not familiar with them )
http://www.expeditionlandrover.info/
http://www.glencoyne.co.uk/200di.htm
https://www.steveparkers.com/conversions/
Long wheel based Series Ones were made for one job and that was to work , which many of them did and were worked to death , as a result they are definitely not as common as the short ones , however , in order to keep them running all sorts of modifications were done to them , engine changes being one of the most common . So if it means keeping yours going for a few more years then putting a TDI into is certainly an option , and one I considered for my own 107” . In the end I put the 2 1/4 ACR breathed on petrol engine that I had in my 86” into it , and it is working well . It can certainly keep up with modern traffic , but obviously at the expense of economy .
Putting a TDI into a Series One has been done loads of times , though I believe there is more work involved putting a 300 in than a 200 . These engines are getting harder to get hold of as they have been snapped up by people putting them into their Series Land Rovers , so finding one might be your first challenge .
If you do put one in then decent sound proofing and the correct engine mounts would be vital , as has been said they are very noisy . Changing gearboxes , axles and brakes would be dependent on how you drive it as you certainly have more power at your disposal . There are converted Series Ones still on their original brakes and axles with seemingly no problems , but I am not able to point you towards any at the moment . As yours is a LWB it already has 11” brakes which may be enough . A disc brake conversion might be necessary but you wouldn’t really know until you started driving it .
I would think fitting an overdrive would be a wise move , even better if you could stretch to a Roamerdrive , but at the thick end of £2,000 , they are not cheap .
Power steering on a LWB would make driving it a lot nicer , but not essential . You will , of course , be aware that the more changes you make to it the greater chance that it won’t meet the new(ish) rules from the DVLA .
Putting a V8 into it would make it no less economical than a standard 2 1/4 petrol but a lot more powerful and sounding great . Worth considering if you are not doing too great a mileage .
Ford V6s and Perkins Prima diesels used to be popular conversions but these engines are more scarce than TDI s so probably not worth considering .
Don’t be conned into thinking that Series Ones are rare , they are not . There are probably more on the road now than there were 20 or 30 years ago . In fact Series Twos are rarer as they were only made for 3 years .
As for devaluing your “investment” , forget it , whatever you do to it won’t reduce it’s value . LWBs are the least expensive of all Series Ones (but most useful) and it looks as if the market has peaked and prices are on the way down again . By steadily modifying my 107” over the last 6 years I have been reducing it value annually , but increasing it’s usability and usefulness .
At risk of boring people who have seen my 107”” loads of times before here is a picture of it in it present form as a trayback . Which is much heavier than it was with a normal rear body but now with it’s replacement engine it can keep up with modern traffic .
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