BEST 'ERGO' ?

ramone:

Carryfast:

ramone:

Carryfast:

ramone:
I`ve just recieved the latest AEC Gazette and inside is an article on the 700 headless engine which was a top secret design with only 1 engine ever being built.Dr Mueller apparently discussed the possibilities of a headless engine with Sir Henry Spurrier but then left the company in 1959 .The reason that the 700 was dropped and then the 500 built was that the engine was too tall which made it unsuitable for normal production vehicles hence the scaled down 500 .The engine was designed at the Research and development department at the Spurrier works .A Norman Tattersall who was a chief engine designer at Leyland was in charge of this project

According to the Knowles report the Leyland 500 engine size ( as opposed to the 700 AEC ) seems to have been set from the outset by Spurrier ( obviously under the advice of Mueller ).While the comments stating that, ''Spurrier’s ‘ambition’ was to see Leyland express trucks plying the ‘autobahns’ of ‘peacetime Germany’ using an engine of 8 litres to do the work of an 11 litre + engine :open_mouth: seem to confirm that and are obviously more than just a coincidence and not something just dreamt up by Knowles. :bulb:

Apparently the engine was nothing to do with AEC ,it was Spurriers baby he died of a brain tumour in 1964 ,the cost of the new tooling and factory in Leyland Lancs was in todays money £100 million ,and like i`ve earlier stated the reason for the downsizing was that the original 700 was too tall for normal production lorries ,just buy a copy of the latest AEC Gazette its all in there

It’s that issue ‘of downsizing of the 700’ which seems to be an erroneous idea of what took place at the outset of the 500 design ‘if’ VALKYRIES’ account of the origins of the 700 being Dr Fogg’s idea are correct.Which seems logical to me because there’s no way that a 700 engine can possibly be ‘downscaled’ it would have to be a totally different engine from the outset.The evidence and logic seem to confirm that the Leyland 500 design was in the pipeline first and the 700 was then thought of later by AEC.It’s just that both designs coincidentally shared the fixed head idea to circumvent the head to block joint issues in the case of using high forced induction boost levels.The Knowles report seems to be specific in Spurrier’s reasoning in the case of using the 500 engine size which seemed to be first and foremost a case of ‘making an 8 litre motor do the work of an 11 litre + one’.

Maybe possibly the idea concerning the ERGO cab being a close fit for the larger engine options was in mind at that point :question: .It’s my bet that the ERGO’s design flaws and engine cooking abilities and the fact that the 500 was never going to be up to the job intended of it can probably be traced back to the involvement of Mueller advising Spurrier in those early years when they were first thought of before their production.Which would explain why Leyland ended up behind it’s competition,such as Mercedes in the case of the LP, :bulb: from that point on.In large part because of all of the,already limited,development budget which had been thrown away on the ERGO cab and 500 engine.Instead of Leyland concentrating it’s efforts on projects like the 3 VTG cab and using the 700 fixed head design as a springboard to eventually making the TL12 competitive in the market assuming either had the potential as opposed to just outsourcing ■■■■■■■ and Rolls options instead. :frowning:

As someone said as for Mueller it was probably a case of mission accomplished. :bulb: :wink:

Quote from the gazette ,Dr Mueller left Leyland in 59 when Sir Henry was looking for more power from diesel engines .Circumstantial evidence makes it clear that he discussed this subject with Dr Mueller and he decided to eliminate the cylinder head gasket in the 0.680 engine enabling it to be highly turbocharged to 300 bhp plus horsepower.The engine wasmost probably based on the 680 components which were laid out in the Research and Development Dept at Spurrier Works and a set of castings were drafted to accomodate them.The result was called the 700 engine,of which only 1 was built and secrecy was maintained over the engine and all its drawings.Only 1 drawing was sent in a misguided routine manner to Chorley (service) and was promptly recalled to secrecy.Placing the 680 camshaft above the tappets increased the overall height of the engine especially at the rear where a large spur gear was mounted for the camshaft drive.Unfortunately this made the engine too tall for normal production vehicles except for underfloor engined coach chassis and Super Beaver and Super Hippo export truck chassis with a high and capacious bonnet.The 700 engine was therefore deemed impracticable for volume production and therefore the fixed head principle was retained but the application was scaled down to an engine of 500 cubic inchesdisplacement . Theres a few pages of this explaining the reasoning behind the fixed head and also the need to switch to metric

:open_mouth:

There can be only two possible scenarios concerning how the 500 engine came into being.If the Knowles report is correct then that scenario can’t be.However ‘if’ the above story is correct it would be that the fixed head started out as the 700 engine.In which case the content of the Knowles report would be a total fabrication which is a bit difficult to believe.‘But’.It would also suggest that instead of going back to the drawing board and designing a totally different smaller capacity 500 engine,which is what it would have taken to have done the job properly,what they actually did was just scale down all the componentry and then expect the thing to work with all the stresses equalling themselves out proportionally in line with the downscaled components :question:. :confused:

That’s in addition to the increase in overall stress levels considering the type of engine speeds the thing would need to run at to provide anywhere near the type of output required to meet it’s design aims.All of which might possibly explain accounts of ‘catastrophic failures caused by split block castings’ etc etc :question: . :bulb:

IE did they in fact make an 8.2 litre engine to do the work of an 11 litre +,with all the implications which that would meant in relation to engine speeds,‘but’ using the same bore stroke ‘ratio’ as the 700 together with just reducing the measurements of it’s components pro rata with the reduction in overall capacity,bearing in mind that the original 700 design would have been running at much lower engine speeds to get similar specific outputs. :open_mouth: :confused: :unamused:

The comparative bore/stroke measurements of the 680,as opposed to the 500,suggest that wasn’t the case with the 500 being a less undersquare,if not square,design than the 680 was,as expected of an engine designed to operate at higher engine speeds.

Which seems to add more weight to the Knowles documented scenario of the 500 being specced by Spurrier and Mueller as a 500 engine from it’s outset and therefore having no connection whatsoever with the Dr Fogg designed 700 other than both coincidentally using the fixed head idea to circumvent the obvious issues concerning high forced induction boost pressures.Therefore it would be interesting to find out what the gazzette was referring to in regards to the specifics concerning the so called ‘downscaling’ of the 700 engine design and the exact timeline concerning the secret 700 prototype as opposed to the 500’s development :question: . :confused:

All the evidence seems to show that it was a matter of backing the wrong choice between two possible engine designs and I’m betting all the ‘secrecy’ and misinformation surrounding the 700 happened ‘after’ that wrong choice had been made by the bean counters together with the ERGO cab and had inevitably proved to be the wrong one in both cases. :bulb: