Buick Rover and BMW V8

[Geoff Kingston]

At the recent BOC concours a fellow Bristol owner and I were admiring the Rover V8 installation in Christopher Balfour's 406, I mentioned that I remembered seeing a magazine article or a book on BMW that suggested that they had sold the rights to their engine to Buick, his recollection from a discussion he had had with one of the former owners of TT Workshops is that Buick had gone to BMW for assistance in the design of their all alloy V8.
Everyone probably knows the history of the Buick Rover deal but the link with BMW does throw up some interesting questions and possibilities, The Automobile magazine asked about this in a feature they did on a BMW 503.
The 502's had both 6 cylinder and V8 engines fitted and I assume, but may be wrong, that no major chassis mods were made and the later engine was designed to fit the space occupied by the earlier engine.
For a while I harboured serious thoughts about buying an old BMW 502 V8 to put the engine into a 401 to make it the sort of car Frazer Nash really wanted, I was too slow off the mark and even 502 V8 wrecks for restoration are now too expensive now to make the project viable.
The Rover V8 however is a very different proposition and I remember at least one 401 or 403 so equipped being actively and successfully sprinted by a BOC member in the mid to late 70's.
The engine we were looking at sat very well in the 406, mated to an automatic gearbox and I think if I remember correctly Christopher said a 407 diff, he told us it was a very good conversion that retained the driving characteristics of the car but obviously with more power.
If this BMW Buick Rover connection is correct it is a fascinating link and raises a lot of what if questions, also it is another option for consideration for returning cars robbed of their original engines to the road.
Hoping someone may know more about the link or can confirm what I have learnt so far.
Geoff.

[Thor]

I have been working with Rover V8s for more than 30 years and I have never seen any concrete evidence for a link to BMW but that is not to say there is none. BMW have always been rather good at aluminium engines so GM/Buick (there was also an Oldsmobile version) may have sought consultancy help from BMW.
The Rover remains a very light engine for its torque output (although modern 4 cylinder turbo engines have overtaken it in this respect).
This is going to look like an advertisement, but I hope it can be taken as simply factual information. This year at JE Engineering Ltd. we will have built about 45 Rover V8s with capacity up to 5.0 litres, and a variety of possible torque and power combinations for road use, up to about 340 bhp. and/or 440 Nm., and we can offer them with 6 speed manual or 6 speed automatic gearboxes (electronically controlled) in 2WD or 4WD form.

[Clive Foster]

According to James Taylor in his book "Rover V8 - the story of the engine" published in June 2017 by Veloce Publishing Ltd there is a rather convoluted path of possible inspiration between the BMW V8 and the Rover / Buick V8.

He says that the BMW engine has design features that were clearly inspired by by the first post war American overhead valve V8 engines. In particular those used by Cadillac and Oldsmobile were of very similar layout, albeit rather larger. It seems that these engines would also have been used as inspiration by the team designing the Buick 215 motor that was to become the Rover V8. Given the similar sources of original inspiration its pretty certain that the Buick team would have looked at the BMW motor to see how well the American layout translated from cast iron into aluminium and what modifications were needed. James suggests that the cylinder block stiffening webs and similar structural features are sufficiently similar to suggest that they are BMW inspired. My alternative view is that the American design teams were using the same textbook calculations. So any BMW link was more along the lines of confirming that what was expected to work would work in practice. Well more or less as the basic block stiffness of the Buick engine was always rather inadequate.

In Rover ownership there was always a pretty continuous process of modification to improve stiffness to keep up with power increases. Normal for the period really because inadequate block stiffness as designed has been a pretty common feature for aluminium block and head engines. Allegedly the current generation have finally nailed it but we shall see. Cast iron is such an incredibly forgiving material that designers often fail to understand how much they are exploiting undocumented characteristics. Aluminium isn't as forgiving. A major reason why the Leyland K series uses through bolt construction. About the only reason that horrid confection Leyland put in the Stag doesn't suffer from terminal block issues is that everything else goes pop first!

Never understood the near-deification of BMW designs. The straight 6 being, in my view, a misguided exploitation of far too many pushrods in pursuit of inadequate inlet gas flow arrangements. Don't mention the idiot VANOS system or L322 installations (actually don't mention the L322 period). At least BMW didn't manage to muck up the P38. Always think it a darn shame that the Rover V8 never got the four valve head and other updating allegedly originally planned for later versions of the P9 sports car after Bill Lyons ensured the project would be dropped as being cheaper and better than the E-Type.

Clive

[Geoff Kingston]

Clive,
That is very interesting I must see if I have that book I know I have a few on BMW and a lot on rover and I think the engine.
I will mention the Range Rover L322 however as I run an early example fitted with the 6 cylinder diesel engine, mine remapped to put out the same power as the car installation, like the P38 before it (I have owned one of those as well) it has its occasional electrical glitches but overall it is a wonderful vehicle and won me over to diesel as opposed to its BMW V8 brother. I still have an early LSE waiting for its turn in the workshop, I have owned Range Rovers almost as long as I have owned Bristols and the only one I would say was totally worthy of being used as a boat anchor was a VM engined diesel, that installation turned it into an evil handling under powered heap of ___.
I liked my P38 and have considered having another but for what I need out of a Range Rover now the L322 is a better proposition , it is a slightly better tow car, is my daily transport and at current values is not worth selling, the LSE is worth far more and if I wanted a P38 it would have to be one of the limited editions and I can't justify the cost for a workhouse left out in all weathers.
The P38 however does not suffer the rust problems of its predecessor or the L322 subframes so I might just be tempted by one of the Japanese imports but only a V8.
Geoff.