Essays : P76 vs P8 vs SD1
Oh, so similar under the skin?
THE conspiracy theory is a great thing, don’t you think? Usually conjured up by fertile imaginations, conspiracy theories are used to explain away conventional wisdoms, and in doing so, challenge what we hold close to our hearts as solid facts. Take for instance, the Rover 75 – for years after it was launched, commentators would gleefully tell us that it was based on an existing BMW platform, even though conventional wisdom told us otherwise. I mean, who would you trust to build a great front wheel drive car – the people who came up with the Mini in 1959, or BMW? Precisely.
The same is happening again with the BMW 1 Series and the ill-fated Rover R30… they’re related, right? Well, possibily. Maybe. Who really knows? Well, we know who knows, but they aren’t talking right now, because the whole thing is still too recent.
But these are no precedents. There are other conspiracy theories in BMC>Rover’s history, many of which, we have yet to get to the bottom of, even after all these years.
Take for instance the Leyland-Australia P76 – here’s a car, seemingly conjured out of nowhere, tailored specifically for the Australian market that owed nothing to any other model in BL’s elephantine model catalogue. And when one thinks that BLMC was moving towards more rational cost management at the time, under the leadership of George Turnbull and John Barber, it seems odd that the company would launch a brand new car with no carry over parts.
Except that this is not quite true. For one, the P76 did pick up the a development of the well-respected E6-Series engine, which at the time lived under the bonnet of the Wolseley Six and Austin Kimberley. Okay, it was a version not yet seen in the BL product range (unlike the 2.2-litre E6-Series engine), and displaced 2623cc, but it was still a parts bin special as its relationship to the 2.2-litre E6 was the same as the 1750cc E4-Series was related to the 1485cc version.
The other P76 engine was a magnificent 4.4-litre version of the Rover V8. Initially earmarked for the Rover P8 project, this engine was a logical upscaling of the original, and most befitting of a new and bold leader of the Rover range. Sadly, the P8 was killed at the eleventh hour of its development cycle, when it became clear that it had no real advantages over the long wheelbase versions of the Jaguar XJ6, and would serve no other purpose than to be an internal competitor to the Browns Lane product.
Well, that was Sir William Lyons’ view anyway – and as he was a BL board member at the time of the P8’s culling, his view was a very important one.
As can be read in the Rover P8 development story, its gestation progressed right through to the pre-production stage – even as far as having its body pressings made up by Pressed Steel in anticipation of a full production run. This would have been a very expensive process, and one that would have been very painful for the company not to see through to its conclusion. But die it did, and in Spring 1971, the entered the realms of a BMC>Rover fascinating might-have-been.
But would all of that development simply gone to waste? That is the main question.
Obviously the P8’s engine and automatic gearbox found their way into the P76, but did anything else? After all, the two car’s proportions, stance and size are almost extremely similar. I put this question to one insider who was very much a part of the Longbridge scene at the time, and therefore not directly involved with the P76 programme. His informed response was interesting: “Can’t be categorical, but a lot of that stuff about P76 being based on P8 tooling/SD1 floorpan is in the same category as R40 being based on 5-Series… ie garbage.”
He went on to say that the P8’s problem was one of being allowed to continue in development for three years after the Jaguar XJ6 became a family member: “The crime was to allow development and expenditure to continue for three years 1968-71 before canning it. XJ6 was on the market in 1968, so there could have been no misunderstanding about overlap. Or was Lyons a really sharp cookie, who waited until the last minute, knowing that it would do more serious damage to Rover that way, thus further protecting his precious Jaguar?”
This is all conjecture of course. To a degree, anyway. The Rover P8 lived as long as it did because Rover could justify its existence while the XJ was only available in cramped standard wheelbase form. And with that in mind, it is hard to believe that none of the the P8 programme found its way into the P76 – this car was so close to production, it hurt, and only the least prudent company would not have sat on what it had, and save it for a later day.
Much of the development of the P76 took place in the UK (over in Abingdon, mainly), and although a different area of BLMC would be responsible for chassis tuning and the like (Roy Brocklehurst of MG fame set-up the chassis in his last major assignment for the company). What is needed is to see the P8’s Pressed Steel engineering drawings, so they can be compared with those of the P76…
|The three cars compared|
|Front track||Rear track||Wheelbase||Suspension||Engine|
|Rover P8||N/A||N/A||108.5in||Front: double wishbones, coil springs.
Rear: De Dion, coil springs, with self-levelling
|Leyland P76||59.4in||59.6in||111in||Front: McPherson struts, coil springs.
Rear: rigid axle, coil springs, radius arms
|Rover SD1||59in||59in||111in||Front: McPherson strut/coil springs.
Rear: Rigid axle, coil springs, radius arms
|V8, 3.5-litres, 6-cyl, 2.3- and 2.6-litres.|
So, although the link between P8 and P76 is tenuous, it is most certainly a possibility – probably in the same way that SD2 and TR7 are genetically linked through their designers, and engineers, and by dint of their being developed in the same timeframe. As Graham Robson relates: “There is much more obvious ‘engineering building block’ symmetry between P76 (1973) and SD1 (1976), than between P76 and P8 – and that 2.5in. difference in wheelbase is significant.”
The link between SD1 and P76 is also circumstantial but interesting nonetheless. For one, their floorpan designs are said to be so similar, they are almost interchangeable. During the SD1’s development phase, a P76 was used as a ‘mule’ – and would that have been the case had they not been so similar? There is also another link between the two: the SD1 used the P76’s straight-six engine (albeit, only in South Africa), and that is enough to make one wonder how much these two projects fed off each other as they went through the BL machine together during the early ’70s…
Phil West, a Leyland Australia enthusiast from Brisbane said: “Well, further to that, when I was working for a Leyland Australia dealership during the era, I once heard from ‘sources who would know’ that the P76 Force 7V hatchback did help form the basis for the hatchback design of the Rover SD1. This was more or less accepted as being fact, and it would not surprise me if this is true. The two vehicles did share some basic design similarities; McPherson front end, five-link rear coil suspension, and power rack & pinion steering.
“As for development, Leyland Australia converted the then-current Holden bodies to P76 specification. The P76 running gear, power units were grafted into the Holden bodies – all of this, while the body design was still being carried out in Italy, and then later at Pressed Steel. The only transmission that would have been shared between the SD1 and P76, was the Borg Warner BW35 autobox. The manual transmission and rear axles were manufactured in Australia by Borg Warner, and were actually shared with the other Australian big car manufacturers; Holden, Ford and Chrysler.
“With the P76 V8, from memory the only identical parts with the Rover V8 were the timing chain, inlet and exhaust valves and valve guides.”
Graham Robson shares this view that there is common DNA between the three cars, and like us, is very keen to get to the bottom of the story. He said: “The styling of the two cars – P8 and P76 – is remarkably similar. My guess is that Michelotti had a hand in both cars (Rover, after all, had been swallowed up by Leyland in 1966/67, when Michelotti was still the golden boy at Leyland-Triumph).”
And in terms of engineering, the P76 and P8 are a distance apart, Graham still feels that there could have been structural commonality: “”Quite a lot of the monocoque structure of the P76, I reckon, could have been ‘rescued’ from tooling already completed for the P8 – or modified from the same tooling.” There is no doubt about the P76/SD1 relationship, though – and the specification table show just how spookily similar the two’s ‘hard-points’ actually are.
Obviously, there are a lot of blanks to fill here, and perhaps there really is smoke without fire, but there are a number of motoring historians out there, that feel it is time to confirm or deny these rumours for good. So, if you worked on any of these projects, or know someone who did, please get in touch with AROnline, because this is a story we really want to get straight before we lose the opportunity forever…