AEC V8

[erf-ngc-european]

[zb]
anorak:

ERF-NGC-European:
Looks like the 6MW cab rebuild for the R-reg Leicester Heavy Haulage unit to me. Robert

You’re right- one of the other photos shows the forward axle position. It’s nice work, either way. The corner panel is especially nice. He’s probably used a wheeling machine to get the compound curve. That or taken a similar panel off another vehicle- I reckon the corner of a Mini roof would not take too much attention from the mallet to look like that.

Gentlemen, do please forgive this quick digression and in doing so recognise that in the great scheme of things all this is connected!

Now then, cab pictures undergoing restoration belong to a 6x4 unit. Here is an explanation of the development of the 4MW cab to the 6MW cab, provided by our own ‘ERF’ on another thread some time ago:

I also found new reference last night to a 6MW cab, a cab which had been previously illusive in all my information, including the master parts lists.
It is mentioned as a cab “…of the same dimension and structure as the set back axle 5MW, but with a forward axle and sharing the 5MW’s improved lighting, heating, ventilation, soundproofing and cab suspension system to reduce driver fatigue”.

Make no mistake chaps, ‘ERF’ really knows his stuff and has an astonishing command of our lorry manufacturing history - believe me, he contributed invaluable material to the thread in which I pursue the legacy of the ERF NGC European.

However, to get back to this 6MW-cabbed ERF, our contributor ‘ERF’ was further able, via his friend the ERF archivist, to furnish us with very precise information about this unit, which I understand is being restored. He reported, again on one my myriad ERF threads as follows:

RAN 648R is chassis number 33865 and is the very last 6MW built.
Model - MDC852.080 (66CU310)
■■■■■■■ NTC 335
Cab not recorded (in pen 6MW).
Despatch date - 29th March 1977
Customer - Leicester Heavy Haulage Ltd.
Uprated by Cossington Commercials to 121924KG on 29th June 1981

Fantastic!

By the way, for pudding, I do know that Marcus Lester (Bubbs) took some amazing pics of this vehicle - it’s possible that he may release some of them on here. In the meantime, here’s another I found online.

Thank you for your patience! Robert

[ramone]

Carryfast:

ramone:
You really are on cloud cukoo if the TL12 had have been launched in 1968 you are saying it wouldnt be able to cut it … against what because it did when it came onto the scene 5 years latter and as for the Marathon cab in 1968 most drivers would havýe given their back teeth for 1 .The Ergo was launched a few years earlier and was a huge step forward and even though it doesnt fit in with your little world the TL12 was reliable and did perform as well but more efficiently than the ■■■■■■■

Firstly how does the Marathon cab beat the 3 VTG cab ?.

As for the TL12 it couldn’t even match the Rolls 305 in terms of output.Let alone later developments of the Eagle up to the TX providing near to 8 mpg at 38t gross.

The 3 VTG was a test bed not a production cab and if you bother to read anything on here and digest BL had signed a deal with Sankey for thousands of Ergos a feal done by the people up in Lancashire so they were stuck with it .As for the TL12 it was a trouble free engine and im not sure where the 305 Rolls comes into this i thought the 220 was your latest motor . Bewick commented on a photo posted not too long ago of a 32/4 Seddon with a RR 220 and said it was the cheapest most basic thing available at the time … he never bought 1

[erf]

Thank you for your kind words above Robert.
Although with my input, I am mostly just a messenger.

I class myself fortunate to learn from many truly wonderful engineers over the years, and meet and learn from people with a fantastic level of knowledge in various fields. I count our own ‘gingerfold’, ‘cav551’ and indeed yourself in there. People with a genuine desire to compile and record accurate details from our great road transport manufacturing history, and then share that information with the rest of us.

I have no problem making credible comparisons, and calling a failure a failure, but to be honest I do find it disappointing when credit for some really innovative thinking 50 years ago contained within that ‘failure’ is berated and treated with disrespect by some on these pages. I am sorry to bore the pants off everyone for the last two pages with BMEP, engine performance comparisons etc, but it helps put across the case of why engineers still regard the AEC V8 engine as so very close to being a success. They got so much of it right first time, including it’s exceptional power output characteristics. Never at any point in the V8 engine development did AEC engineers think they would just have the one shot at it, they were working to normal development practice of going back to the design stage after prototype testing had given them much needed information, and that never happened. Keith Roberts must have been extremely disappointed that his design didn’t get the further development it needed, and kicked himself that the prototype engines were built with too much emphasis on weight, size and cost, which compromised his design just too much, bringing it too close to the engineering limits of available materials and technology at the time.

Re the digression - the R’reg ex LHH ERF 6MW is local to me now. The cab is painted back in LHH livery, but at the moment it’s owner is wrestling with it’s seized ■■■■■■■ NT335 engine, which was unexpected to say the least!.

[gingerfold]

Following on from ERF’s well presented post above, and thank you for your kind words, by the way. My own experience is at the sharp end of vehicle operations and the day-to-day problems, and satisfaction that brings to the job. When I was involved with the AEC Society for many years I was fortunate to meet and talk to several former AEC employees from various departments within the company. These were people ranging from Regional Depot Managers, and remember AEC was no small company, it did have its own Regional Service Depots with full workshops facilities. After the Leyland takeover some of AEC’s depots were merged with Leyland’s regional depots and one or two AEC men were in charge of the combined depots. I also met service engineers, men on the road who visited operators of AECs and Leylands to learn of any operational issues and deal with them, passing feed back to Southall or Leyland. I also met men from the Southall design, development, and testing departments. ALL these people were skilled, qualified and experienced engineers, either coming up through the ranks via apprenticeships, or through engineering graduate intake. These were some of the most critical people of AEC products I have ever met because their one aim in their working lives was to make their products better. Surely this is what engineering is all about. Never to be complacent and always to strive for improvement? So yes, we can criticise the failures but as ‘railstaff’ so aptly commented “they were triers”. But there is never any place for endless and needless derogatory comments about anyone’s working life and career when none of us outsiders know now, or will ever know what it was like to be involved at the sharp end of a company such as AEC or Leyland, or ■■■■■■■■ or Rolls Royce, or Gardner.

[dave_docwra]

After reading the CM article on the V8 which I thank ERF for taking the time to share, I am convinced that Mr Roberts was a very forward thinking engineer & has to be credited with some great advancements in diesel engine technology.

Dave.

[ramone]

dave docwra:
After reading the CM article on the V8 which I thank ERF for taking the time to share, I am convinced that Mr Roberts was a very forward thinking engineer & has to be credited with some great advancements in diesel engine technology.

Dave.

Yes i agree , ERF is putting some great information on here and Keith Roberts certainly seemed to know his stuff .

[carryfast]

ramone:
Roberts certainly seemed to know his stuff .

Let’s get this right Robert’s gets the credit for its design and Stokes gets the blame for its failure.

While the supposedly equally clever Perkins designers took an opposing view to his and turn out the 510 which has a specific torque of 45 lb/ft per litre v the 13.1 litre AEC V8’s best shot of 48 lb/ft per litre.All that with around almost 25% less bore size and the same stroke.Notwithstanding any test standards differences which won’t account for that discrepancy v the Robert’s script of piston area supposedly being king.Also bearing in mind that the 510 was a much earlier design that the 13.1 litre AEC and also bearing in mind that we supposedly can’t compare the Rolls Eagle 220 Mk 2 let alone the Mk3 with any AEC V8 because that supposedly ain’t fair according to the AEC fan boys.

[cav551]

ERF:
Thank you for your kind words above Robert.
Although with my input, I am mostly just a messenger.

I class myself fortunate to learn from many truly wonderful engineers over the years, and meet and learn from people with a fantastic level of knowledge in various fields. I count our own ‘gingerfold’, ‘cav551’ and indeed yourself in there. People with a genuine desire to compile and record accurate details from our great road transport manufacturing history, and then share that information with the rest of us.

I have no problem making credible comparisons, and calling a failure a failure, but to be honest I do find it disappointing when credit for some really innovative thinking 50 years ago contained within that ‘failure’ is berated and treated with disrespect by some on these pages. I am sorry to bore the pants off everyone for the last two pages with BMEP, engine performance comparisons etc, but it helps put across the case of why engineers still regard the AEC V8 engine as so very close to being a success. They got so much of it right first time, including it’s exceptional power output characteristics. Never at any point in the V8 engine development did AEC engineers think they would just have the one shot at it, they were working to normal development practice of going back to the design stage after prototype testing had given them much needed information, and that never happened. Keith Roberts must have been extremely disappointed that his design didn’t get the further development it needed, and kicked himself that the prototype engines were built with too much emphasis on weight, size and cost, which compromised his design just too much, bringing it too close to the engineering limits of available materials and technology at the time.

Re the digression - the R’reg ex LHH ERF 6MW is local to me now. The cab is painted back in LHH livery, but at the moment it’s owner is wrestling with it’s seized ■■■■■■■ NT335 engine, which was unexpected to say the least!.

Thank you ERF for your kind comments.

I am sorry but I am going to repeat something I mentioned before even though it was off topic, because it illustrates a very similar story and the above reminds us that this is what happens with a new design… In this instance the project did eventually come right, but there were so many returns to the drawing board with fundamental changes in design that the team must have wondered if it would ever come right… I am NOT repeat NOT talking about the length of anything, but far more significant changes in design. The start of the project as said before shows stubborness, arrogance and repeated failure. It took many, many attempts to get it right. It took input from another manufacturer to help make it a success.

The article is a little hard to follow with just one quick skim through, but the first paragraphs which set the scene are important. Figure 13 need particularly close study to appreciate the scale of changes made. The story also indicates just how long the engine had been in production before the basic number of castings was decided upon. Also very clear is that there were considerable problems in service.

Today all this is virtually forgotten with the engine viewed through those rose coloured glasses which time and the subsequent story overshadow. It was eventually a phenominal success thank God, but it took some getting there.

enginehistory.org/Piston/Rol … /RHM.shtml

[carryfast]

cav551:
I am sorry but I am going to repeat something I mentioned before even though it was off topic, because it illustrates a very similar story and the above reminds us that this is what happens with a new design… In this instance the project did eventually come right, but there were so many returns to the drawing board with fundamental changes in design that the team must have wondered if it would ever come right… I am NOT repeat NOT talking about the length of anything, but far more significant changes in design. The start of the project as said before shows stubborness, arrogance and repeated failure. It took many, many attempts to get it right. It took input from another manufacturer to help make it a success.

The article is a little hard to follow with just one quick skim through, but the first paragraphs which set the scene are important. Figure 13 need particularly close study to appreciate the scale of changes made. The story also indicates just how long the engine had been in production before the basic number of castings was decided upon. Also very clear is that there were considerable problems in service.

Today all this is virtually forgotten with the engine viewed through those rose coloured glasses which time and the subsequent story overshadow. It was eventually a phenominal success thank God, but it took some getting there.

enginehistory.org/Piston/Rol … /RHM.shtml

The better analogy in this case would be blind alley of the Vulture.When they could have put all that wasted effort into getting the Griffon up and running and in the Spitfire hopefully by 1940.The difference being that they ditched the Vulture long before it could take out bomber command and not only did the Mk XIV Spit actually happen they did it in time to provide the essential air supremacy over the FW 190,especially D9,in the skies over Europe after D Day that the Mk 9 and Mustang couldn’t.

IE go big or go home and the leverage part of the equation is just as if not more important as force at the piston and con rod.No surprise either that,like the AEC V8,supposed ‘lack of development’,is often used as an excuse for a crap basic design and architecture in the case of Vulture.As opposed to the solid foundation of the Griffon’s architecture and even to a lesser extent Merlin.No rose tinted specs there.

youtube.com/watch?v=MGOda-uWRHw

[dave_docwra]

Interesting read on the Merlin engine, I think we have to remember these guys were designing all this with slide rule,paper & pencils & certainly no PC’s, so to be fair a lot of this stuff was trial & error.

The only question I have was the PV-12 ever fitted in a GUY .

Dave.

[erf]

Very interesting re the RR Merlin.

Have a look at this ATV news clip from April 1974.
No AEC V8’s of course, but plenty of new Marshal’s!.
The subject matter is…’interesting’ !?

macearchive.org/films/atv-to … orry-sales

[newmercman]

I like his hat.

Sent from my SM-G950W using Tapatalk

[gingerfold]

Well he got that bit wrong about the future of British Leyland. Surprising, because Mr Richardson was a very astute businessman and I believe that he developed the Merry Hill Shopping Centre. No doubt some of our West Midlands contributors will know more.

[erf]

Carryfast:

ramone:
Roberts certainly seemed to know his stuff .

Let’s get this right Robert’s gets the credit for its design and Stokes gets the blame for its failure.

While the supposedly equally clever Perkins designers took an opposing view to his and turn out the 510 which has a specific torque of 45 lb/ft per litre v the 13.1 litre AEC V8’s best shot of 48 lb/ft per litre.All that with around almost 25% less bore size and the same stroke.Notwithstanding any test standards differences which won’t account for that discrepancy v the Robert’s script of piston area supposedly being king.Also bearing in mind that the 510 was a much earlier design that the 13.1 litre AEC and also bearing in mind that we supposedly can’t compare the Rolls Eagle 220 Mk 2 let alone the Mk3 with any AEC V8 because that supposedly ain’t fair according to the AEC fan boys.

You really do spew out the most inaccurate nonsense within your venomous diatribe CF.
My posts have nothing at all to do with being an …‘AEC fan boy’ (although there might be a T-shirt line in there… )

Having had a very strong association with one of the most successful commercial vehicle products that this country has produced, I have tremendous respect for ALL engineering development because I have a comprehensive grasp of the monumental effort, expense, trial, error and innovative thinking that it requires, and a comprehensive grasp of credible engineering comparisons.

So, reeling from recent failure, you have now moved on from comparing AEC V8 vs Rolls Royce Eagle engines, to Perkins of all makes!. Very good. As you know, we like a trier here!.
Last week you were completely adamant that BMEP was king. Now we are back to this rather odd torque vs capacity analogy, strange as last week you were the one hammering home the point that BMEP is directly related to torque…!

No matter, as you like.

So, forgetting for now the 13.1 litre AEC engine, because that will just make your position worse, we will take the 12.1 litre AEC V8 AV740 with a BMEP of 115 psi, against the Perkins V8 510 with a BMEP of 112 psi.
The AEC engine achieved its higher BMEP through clever and innovative combustion using a compression ratio of 16:1.
The Perkins, much more traditional in it’s design, used a higher compression ratio of 17.5:1 to achieve a lower BMEP.

Not looking good for you so far, is it?.

The Perkins produces it’s maximum torque at 1500 RPM, 100 RPM higher than the AEC.
Maximum BHP for the Perkins is achieved at 2800 RPM, 200 RPM higher than the AEC.

Your analogy is really starting to look shaky now, isn’t it?.

So, lets look at your ‘bespoke’ comparison.
Perkins V8 510 - 45.45 lb/ft per litre.
AEC V8 AV740 - 51.32 lb/ft per litre.

So that is actually a 13% increase in relative torque over the Perkins, all within a much heavier engine that is producing it’s maximum performance figures at 7+% lower speed.

…back in the REAL WORLD it’s all gone terribly wrong for your comparison. Again.

And just for the record, Perkins were still playing around with indirect injection V8 prototypes until well into 1963. The AEC V8 design had already mandated the use of direct injection a full year previously, so you can’t possibly say that the Perkins 510 is a ‘much earlier design’.

[carryfast]

ERF:

Carryfast:

ramone:
Roberts certainly seemed to know his stuff .

Let’s get this right Robert’s gets the credit for its design and Stokes gets the blame for its failure.

While the supposedly equally clever Perkins designers took an opposing view to his and turn out the 510 which has a specific torque of 45 lb/ft per litre v the 13.1 litre AEC V8’s best shot of 48 lb/ft per litre.All that with around almost 25% less bore size and the same stroke.Notwithstanding any test standards differences which won’t account for that discrepancy v the Robert’s script of piston area supposedly being king.Also bearing in mind that the 510 was a much earlier design that the 13.1 litre AEC and also bearing in mind that we supposedly can’t compare the Rolls Eagle 220 Mk 2 let alone the Mk3 with any AEC V8 because that supposedly ain’t fair according to the AEC fan boys.

You really do spew out the most inaccurate nonsense within your venomous diatribe CF.
My posts have nothing at all to do with being an …‘AEC fan boy’ (although there might be a T-shirt line in there… )

Having had a very strong association with one of the most successful commercial vehicle products that this country has produced, I have tremendous respect for ALL engineering development because I have a comprehensive grasp of the monumental effort, expense, trial, error and innovative thinking that it requires, and a comprehensive grasp of credible engineering comparisons.

So, reeling from recent failure, you have now moved on from comparing AEC V8 vs Rolls Royce Eagle engines, to Perkins of all makes!. Very good. As you know, we like a trier here!.
Last week you were completely adamant that BMEP was king. Now we are back to this rather odd torque vs capacity analogy, strange as last week you were the one hammering home the point that BMEP is directly related to torque…!

No matter, as you like.

So, forgetting for now the 13.1 litre AEC engine, because that will just make your position worse, we will take the 12.1 litre AEC V8 AV740 with a BMEP of 115 psi, against the Perkins V8 510 with a BMEP of 112 psi.
The AEC engine achieved its higher BMEP through clever and innovative combustion using a compression ratio of 16:1.
The Perkins, much more traditional in it’s design, used a higher compression ratio of 17.5:1 to achieve a lower BMEP.

Not looking good for you so far, is it?.

The Perkins produces it’s maximum torque at 1500 RPM, 100 RPM higher than the AEC.
Maximum BHP for the Perkins is achieved at 2800 RPM, 200 RPM higher than the AEC.

Your analogy is really starting to look shaky now, isn’t it?.

So, lets look at your ‘bespoke’ comparison.
Perkins V8 510 - 45.45 lb/ft per litre.
AEC V8 AV740 - 51.32 lb/ft per litre.

So that is actually a 13% increase in relative torque over the Perkins, all within a much heavier engine that is producing it’s maximum performance figures at 7+% lower speed.

…back in the REAL WORLD it’s all gone terribly wrong for your comparison. Again.

And just for the record, Perkins were still playing around with indirect injection V8 prototypes until well into 1963. The AEC V8 design had already mandated the use of direct injection a full year previously, so you can’t possibly say that the Perkins 510 is a ‘much earlier design’.

Firstly I was mainly using the Perkins to make the case for go large or go home ( supposed clever Perkins designers ).IE a comparison of two lame ducks just that one was worse than the other and the Perkins doesn’t seem to have been aimed out of its league in the max weight long haul sector.Like the AEC should have been used in lesser weight rigids.But no Roberts’ counterpart Fogg decided that the 500 was the best way to sort that out.

However the other basic premise remains.The AEC ended up with a specific torque figure of around just 3 lb/ft per litre more than the Perkins with around 25 % more piston area.Which, together with the example of the Scania V8,blows Roberts’ dodgy ideas out of the water.It’s also clear that,unlike the Scania,there never was a turbocharged AEC V8 production example,let alone one from day 1.Not because of Roberts’ lame excuses that it would come later,but because the thing would have been throwing con rods out the side of the block,or at least melting its end bearings,before it finished its durability runs ( see starting handle v crankshaft analogy ).

As I said limited formula race car design thinking applied to heavy truck engine design.In that it’s torque and lots of it which is used to move a truck down the road.Not silly peak power figures made by equally silly high engine speeds.

While to be fair Roberts’ failed piece of unconventional ‘thinking’ did help to bring down a massive part of the uk truck manufacturing sector and all the resulting job losses that meant for loads of innocent workers.While many of his AEC fan admirers then put the blame for that on Leyland and Stokes and Leyland’s supposed militant workers. Which really deserves nothing less than a venomous response in their defence.

[zb_anorak]

ERF:
…The AEC engine achieved its higher BMEP through clever and innovative combustion using a compression ratio of 16:1.
The Perkins, much more traditional in it’s design, used a higher compression ratio of 17.5:1 to achieve a lower BMEP…

The AEC may have been helped by its overquare geometry allowing bigger inlet valves, to the end of superior volumetric efficiency. We’re right in the detail now. I feel the need to read a bit more on the subject of IC engine design.

Carryfast:
…While to be fair Roberts’ failed piece of unconventional ‘thinking’ did help to bring down a massive part of the uk truck manufacturing sector and all the resulting job losses that meant for loads of innocent workers.While many of his AEC fan admirers then put the blame for that on Leyland and Stokes and Leyland’s supposed militant workers. Which really deserves nothing less than a venomous response in their defence.

The simple fact is that the engine was forced into production with at least another year of work still to be done. It’s all down black and white in this thread. The only possible culprit for that is the MD. A professional engineer in Stokes’ position would never have allowed such a foolish risk to be taken. All of the people who have experience of the engine report that it would have been fine if the extra development work had been done. The decision to develop a high speed overquare diesel was indeed ambitious, but four other makers got it right.

[newmercman]

You were doing well for a while Carryfast, then you revert back to your old self and your posts become, to put it bluntly, annoying. To the point that I get to a certain phrase and move on to the next post, a strategy that many of us adopt. So really, you’re wasting your time with everything you say from that point onwards.

And… to help you further, between you and I, you’re talking out of your arse, you keep comparing the V8 with full production engines, using all manner of different parameters to prove a point that only exists in your disturbed mind.

Now, read this and let it sink in, then read it again and again until you understand how it sheds a completely different light onto the AEC V8 design from the one you mistakenly have now. THE AEC V8 WAS A PROTOTYPE ENGINE, IT DID NOT GET THE NECESSARY DEVELOPMENT WORK TO TURN IT INTO A FULL PRODUCTION ENGINE. IT WAS FLAWED IN MANY WAYS AND NEEDED SOME SIGNIFICANT CHANGES TO OVERCOME THE PROBLEMS DISCOVERED DURING PRE PRODUCTION OPERATIONAL TRIALS CONDUCTED WITH SEVERAL MAJOR CUSTOMERS.

Nobody knows who made the decision to put it into production before it was ready, but someone did and as Stokes was top man at the time, the blame lies at his feet, if A ship sinks, the captain goes down with it. Nobody has said that he personally made the phone call to Southall, just as nobody has said that Southall gave any indication that the V8 was ready to go into full production, quite the opposite in the case of the latter.

it’s beyond question that any of the engines that you have used in your comparisons were better, but each and every one of them had been through the complete research and development cycle and had all the kinks ironed out, so any comparisons between a full production engine and the AEC V8 are like comparing an iPod to an 8 track.

Sent from my SM-G950W using Tapatalk

[cav551]

[zb]
anorak:
The AEC may have been helped by its overquare geometry allowing bigger inlet valves, to the end of superior volumetric efficiency. We’re right in the detail now. I feel the need to read a bit more on the subject of IC engine design. :

Exactly, you can have the greatest leverage advantage possible, but if you cannot get the air in and out again it is going to be a lemon. Which is exactly what happened with the type HOE7 Crossley diesel engine. The thing was strangled and asthmatic. IIRC when Crossley Motors were taken over by AEC the parent company’s engineers set to work on sorting out the breathing problems. However the engine like its predecessors already had a bad reputation and Crossley chassis were very soon powered by AEC engines.

[erf]

Carryfast:

ERF:
So, lets look at your ‘bespoke’ comparison.
Perkins V8 510 - 45.45 lb/ft per litre.
AEC V8 AV740 - 51.32 lb/ft per litre.

So that is actually a 13% increase in relative torque over the Perkins, all within a much heavier engine that is producing it’s maximum performance figures at 7+% lower speed…

…The AEC ended up with a specific torque figure of around just 3 lb/ft per litre more than the Perkins with around 25 % more piston area…

Errr - I think the battery is flat in your calculator on both counts there.
I’m sure if you need ‘[zb] anorak’ to help you with the maths, he will…

[erf]

M