Carryfast:
gingerfold:
Carryfast:
For me the whole topic revolves around the question of what stood in the way of the obvious possibility,of the AEC V8 being a 130 x 142 design and put in the 3 VTG job done.How difficult could that have been.
[/quote]Until someone digs out the ■■■■■■■ V8 patents that Keith Roberts and Bob Fryars studied, reads them, and understands them, then we will never know the answer to your question. No doubt they would have also taken the proper legal advice from patent lawyers.
If I’ve read it right that was all about some obscure deals with Guy and/or BMC which supposedly meant the need for a silly short stroke V8 to fit under their obviously equally silly cab designs.With the result that they settled on an even sillier 130 x 114 engine design to meet the spec.Although we know that Guy at least went on to fit a 14 litre ■■■■■■■ under their the Big J.However we know that by 1964 all that no longer existed.However we also know t
hat Roberts and co were ‘delighted’ when they were told to resurrect their silly BMC/Guy design project and to fit it under the Mandator Ergo cab instead.While Fryers also says elsewhere in a CM article that they were actually ‘horrified’ at the instruction.In which case no my question still stands.In that we know during this time the 3 VTG was also on the drawing board meaning that the original long gone and luckily still born possible BMC or Guy tie up no longer existed and with it the need for the silly engine to sit under the silly cab.So what did they do.They ditched the 3 VTG and any idea of making a proper V8 along the lines of the Scania and carried on with the idea of making the silly short stroke engine to fit under the equally silly Ergo cab.Bearing in mind that there was no big market out there for a 300 + hp V8 dustcart even if by some miracle they succeeded in extracting that amount of reliable power from their silly motor.
On that note what if the whole unbelievable story above is actually totally bs to cover what actually happened.In that Scania held enough of a financial interest in AEC to have been able to scupper the Leyland deal at any time if AEC dared to tread on Scania’s toes by making a proper 130 x 142 V8 and then put it in the 3 VTG.
Just an observation of no particular relevance, the larger capacity version of the Mercedes OM440 series was 130 x 142 but that was 1990. Used in all the normally aspirated versions and the turbos when fitted with EDC.
ERF:
The history of both Mr Roberts and Mr Porkess are both very interesting…1
0
The bloke in the top photo looks a right nasty ■■■■■■■■ I know, I know ! Looks aren’t everything but surely the AEC publicity dept. could have got a better shot ! But maybe this was the best they could get ! I wouldn’t mind seeing the ones on the cutting room floor then 
Bewick.
So if I understand this correctly, the AEC design team sat down for tea and biscuits and decided to make a V8 engine to compete with a Scania 140, which was to be released to the market some years in the future.
Or…
At the time the average power rating in heavy trucks was around the 180hp range and the motorway network was yet to exist.
The British road haulage industry was largely dominated by BRS, who were also supping tea over at Scammell and coming up with a replacement for their preferred choice of lorry, the Bristol. They settled on the Crusader, with a day cab and the Rolls Royce Eagle engine at 220hp as their Jack of all trades tractor unit.
Meanwhile in Southall the idiots at AEC decided not to build something that would blow the doors off the Scania that didn’t yet exist, no they decided to make an engine that would fit under the soon to be released Ergomatic cab, this made it necessary to be of a compact design, a relatively large capacity engine, but one that would take up less room under the low mounted Ergomatic cab than an inline 6 of similar capacity.
In order to achieve this and not infringe the copywrited bore and stroke dimensions of the ■■■■■■■ engine, they decided on an oversquare design, yes it would have to be high revving, but as the go to transmission of the time was a 6spd, that wouldn’t be a problem, quite the opposite in fact.
On the surface, a sound philosophy, creating a range of lorries, sharing the same cab, from a 4x2 16ton rigid and 24/28ton tractor unit, through 6x2, 6x4, 8x2 and 8x4 chassis to the tractor units in 4x2, 6x2 and 6x4 format, with options of an inline six and V8 engine. Pretty much a horse for every course, keep up with demands of existing customers and win some new ones.
Then a merger with Leyland and cash flow was serverly compromised, meaning the flaws that showed up during testing of the V8 were not addressed and the project was shelved. Until a message came down from above to put the unfinished project into production.
But it’s not ready said the idiots in Southall, don’t worry about that said the big wigs at BL, you won’t believe the balls up of the fixed head inline six we’re about to release, just get it built and we’ll sort it out as we go, the Standard Triumph purchase is killing us and we need a few quid in the bank.
We can’t said Southall, it’s a dog, it needs a lot more development and testing, it will be a disaster. Oh yes you can said BL, don’t worry about upsetting customers, where else are they going to buy lorries from? Atkinson and the other lot from Cheshire can’t get enough engines from Hugh Gardner and Rolls Royce are in cohorts with BRS and Scammell. What are the lorry men going to do? Buy lorries from the bloody Germans and the white flag wavers across the channel? Just get it done.
The rest as they say, is history…
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That’s about right Mark, we’ve provided Carryfast with the facts, from the horses mouth so to speak, in post after post, yet he still doesn’t accept any of it. What a pity, but I’m sure that there are many members of TN who will have learned something new from this thread, whether they have contributed or not.
Carryfast:
gingerfold:
Yes, very true. One of the parameters of the Leyland design brief given to Michelotti for the Ergomatic was low entry for ease of access for the driver. However, with the 500 engine and later developments for the Marathon they soon found out that the low entry idea was a mistake. Perhaps that’s why the Berliet cab was considered for the Marathon, but all manufacturers would go to the high cab idea, not for the aesthetics of cab design but for the very good reasons of engine placement and chassis layout.I must say the modern high cabs are a pain in the posterior if I have to shunt half a dozen trailers or so in our yard, as I have to do every Friday morning to fit everything in for weekend. Climbing up and down all those steps! If there’s a DAF CF handy I always use that, fewer steps. Probably an age thing.
Just think what might have been if Scania had ditched the 140 on the grounds of it being too high to make a good yard shunter or dustcart or local delivery wagon.
The clue being that you don’t need a 300 hp + V8 powerd truck for that job.
So there we have it the 3 VTG with a 130 x 142 V8 in it would never have been viable because it would have been no good as a yard shunter or a dustcart or local delivery wagon.
Then some people say it was all the fault of the workers.
Carryfast you’re a scream, but you obviously have no sense of humour yourself. Go and lie down in a darkened room for a day or two, you’re seriously embarrassing yourself.
gingerfold:
That’s about right Mark, we’ve provided Carryfast with the facts, from the horses mouth so to speak, in post after post, yet he still doesn’t accept any of it. What a pity, but I’m sure that there are many members of TN who will have learned something new from this thread, whether they have contributed or not.
You beat me to it!
I have seen previous topics here on TN that have been ‘cleaned up’ by our moderators removing irrelevant waffle and repetition. If it were removed from this thread, leaving in just one post out of the 400 (or so it seems!) giving an entitled opinion on 130mm bore x 142mm stroke, we would probably have the most concise and readable history of the Mandator V8 since your book!.
Bewick:
ERF:
The history of both Mr Roberts and Mr Porkess are both very interesting…1
0The bloke in the top photo looks a right nasty [zb], I know, I know ! Looks aren’t everything but surely the AEC publicity dept. could have got a better shot ! But maybe this was the best they could get ! I wouldn’t mind seeing the ones on the cutting room floor then
I dare bet you wouldn’t be late for work more than once with him as your boss Dennis!.
newmercman:
So if I understand this correctly, the AEC design team sat down for tea and biscuits and decided to make a V8 engine to compete with a Scania 140, which was to be released to the market some years in the future.Or…
At the time the average power rating in heavy trucks was around the 180hp range and the motorway network was yet to exist.
The British road haulage industry was largely dominated by BRS, who were also supping tea over at Scammell and coming up with a replacement for their preferred choice of lorry, the Bristol. They settled on the Crusader, with a day cab and the Rolls Royce Eagle engine at 220hp as their Jack of all trades tractor unit.
Meanwhile in Southall the idiots at AEC decided not to build something that would blow the doors off the Scania that didn’t yet exist, no they decided to make an engine that would fit under the soon to be released Ergomatic cab, this made it necessary to be of a compact design, a relatively large capacity engine, but one that would take up less room under the low mounted Ergomatic cab than an inline 6 of similar capacity.
In order to achieve this and not infringe the copywrited bore and stroke dimensions of the ■■■■■■■ engine, they decided on an oversquare design, yes it would have to be high revving, but as the go to transmission of the time was a 6spd, that wouldn’t be a problem, quite the opposite in fact.
On the surface, a sound philosophy, creating a range of lorries, sharing the same cab, from a 4x2 16ton rigid and 24/28ton tractor unit, through 6x2, 6x4, 8x2 and 8x4 chassis to the tractor units in 4x2, 6x2 and 6x4 format, with options of an inline six and V8 engine. Pretty much a horse for every course, keep up with demands of existing customers and win some new ones.
Then a merger with Leyland and cash flow was serverly compromised, meaning the flaws that showed up during testing of the V8 were not addressed and the project was shelved. Until a message came down from above to put the unfinished project into production.
But it’s not ready said the idiots in Southall, don’t worry about that said the big wigs at BL, you won’t believe the balls up of the fixed head inline six we’re about to release, just get it built and we’ll sort it out as we go, the Standard Triumph purchase is killing us and we need a few quid in the bank.
We can’t said Southall, it’s a dog, it needs a lot more development and testing, it will be a disaster. Oh yes you can said BL, don’t worry about upsetting customers, where else are they going to buy lorries from? Atkinson and the other lot from Cheshire can’t get enough engines from Hugh Gardner and Rolls Royce are in cohorts with BRS and Scammell. What are the lorry men going to do? Buy lorries from the bloody Germans and the white flag wavers across the channel? Just get it done.
The rest as they say, is history…
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FFS it was a conspiracy to kill off BL , and it doesnt matter that the V8 Scania didnt exist AEC should have known that they would build one pretty soon so needed to build something to compete. A one size fits all cab will never work and thats why they never sold any . It`s just a suprise or even a miracle that AEC lasted so long in the industry. What AEC really needed was someone who could predict the future and make a flawless engine , infact a flawless range of vehicles that would be as good if not better than vehicles being produced 50 years later then they may have stood a chance .
newmercman:
So if I understand this correctly, the AEC design team sat down for tea and biscuits and decided to make a V8 engine to compete with a Scania 140, which was to be released to the market some years in the future.Or…
At the time the average power rating in heavy trucks was around the 180hp range and the motorway network was yet to exist.
The British road haulage industry was largely dominated by BRS, who were also supping tea over at Scammell and coming up with a replacement for their preferred choice of lorry, the Bristol. They settled on the Crusader, with a day cab and the Rolls Royce Eagle engine at 220hp as their Jack of all trades tractor unit.
Meanwhile in Southall the idiots at AEC decided not to build something that would blow the doors off the Scania that didn’t yet exist, no they decided to make an engine that would fit under the soon to be released Ergomatic cab, this made it necessary to be of a compact design, a relatively large capacity engine, but one that would take up less room under the low mounted Ergomatic cab than an inline 6 of similar capacity.
In order to achieve this and not infringe the copywrited bore and stroke dimensions of the ■■■■■■■ engine, they decided on an oversquare design, yes it would have to be high revving, but as the go to transmission of the time was a 6spd, that wouldn’t be a problem, quite the opposite in fact.
On the surface, a sound philosophy, creating a range of lorries, sharing the same cab, from a 4x2 16ton rigid and 24/28ton tractor unit, through 6x2, 6x4, 8x2 and 8x4 chassis to the tractor units in 4x2, 6x2 and 6x4 format, with options of an inline six and V8 engine. Pretty much a horse for every course, keep up with demands of existing customers and win some new ones.
Then a merger with Leyland and cash flow was serverly compromised, meaning the flaws that showed up during testing of the V8 were not addressed and the project was shelved. Until a message came down from above to put the unfinished project into production.
But it’s not ready said the idiots in Southall, don’t worry about that said the big wigs at BL, you won’t believe the balls up of the fixed head inline six we’re about to release, just get it built and we’ll sort it out as we go, the Standard Triumph purchase is killing us and we need a few quid in the bank.
We can’t said Southall, it’s a dog, it needs a lot more development and testing, it will be a disaster. Oh yes you can said BL, don’t worry about upsetting customers, where else are they going to buy lorries from? Atkinson and the other lot from Cheshire can’t get enough engines from Hugh Gardner and Rolls Royce are in cohorts with BRS and Scammell. What are the lorry men going to do? Buy lorries from the bloody Germans and the white flag wavers across the channel? Just get it done.
The rest as they say, is history…
Sent from my SM-G950W using Tapatalk
Oh wait.
It’s 1964.
They all sat down for tea and biscuits with the conclusion that we need a ‘’ 300 hp + ‘’ V8 powered long hauler’'.Let’s say having foreseen the need for 10 hp per tonne before anyone else had.
All that’s more or less documented fact.
Between then and 1968 they are also working on a nice big cab over Pete knock off cab which is also there and in place by 1968.Which of course would go perfectly with the proven 690 based 130 x 142 V8 to meet the aforesaid spec.
The first production example is ready in mid 1969.Just in time to beat Scania’s 140 onto the market which Scania are known to have been working on since 1962.Also taking full advantage of the recently completed North/South and East/West and still rapidly expanding motorway network.The point being enthusiastically hammered home by AEC’s marketing dept to rapturous applause by CM’s journalists.The recently introduced Scammell Crusader is now to be stopped with production capacity given over to helping AEC in making the new truck which will also use the Rolls Eagle as offered in the outgoing Crusader.All further development of the 760 is therefore to be dropped.BRS’s fleet engineer is said to be over the moon with the surprise new updated tilt cab and retention of the Rolls Royce engine option.With all further AEC development budget going into further development of its groundbreaking V8.While the futuristic American type 3 VTG cab is foreseen to meet all of Leylands max weight premium truck needs for at least the next decade possibly beyond.With interest in the new AEC V8 already being expressed by specialist hauliers looking for suitable products for use in the rapidly growing International and even Middle East road transport market sectors.
The rest is history if only. 
Make no mistake either you’re saying that Scania got it wrong in the case of the 140 and AEC got it right with the V8 Mandator or vice versa there’s no middle ground or ifs or buts in that.Bearing in mind the question how can you possibly fix the basic problem of trying to make a 114 mm stroke buzz bomb compete with Scania’s ( or Merc’s ) train engine ?.
gingerfold:
That’s about right Mark, we’ve provided Carryfast with the facts, from the horses mouth so to speak, in post after post, yet he still doesn’t accept any of it. What a pity, but I’m sure that there are many members of TN who will have learned something new from this thread, whether they have contributed or not.
Yes, most of it has been very interesting even though I had no experience of the engine. We did run 505’s in Marshall’s before my time at Tilcon and apparently they blew head gaskets regularly! I occasionally used to attend motorcaravan rallies with the designer of the Perkins V8 which was an engine I did have some dealings with when fitted in Mastiff’s. We both had VW campers and he was interesting to ‘talk shop’ with as well, but of course he was enjoying a weekend away from work so I didn’t mither him too much! Keep up the good work.
Pete.
reading the facts & the history of AEC on this thread has been very educational, I would like to thank all the learned contributors for their input.
Thanks Dave.
Carryfast, I don’t believe anybody has said that the AEC V8 was a success, neither in design or operation. It is a belief that it could, with further development, have been a success, after all, that’s what engineers do, they come up with methods to make things work, there are countless examples of engineering triumphs to prove this, take a Porsche 911 as an example, in its current form it’s said to be one of the best handling sports cars ever made and yet the whole concept of the 911 is flawed, an engine mounted behind the rear axle should be a recipe for disaster, yet thanks to engineering it is not.
So with a bit of development and a few fundamental changes, there is no doubt that the V8 could have been engineered to overcome its faults, as we know, it never happened.
However, it did go into production and as such it’s part of history, that history has told us that when it was running right, it went like the clappers and was a huge leap forward in performance compared to the previous engines from AEC and many others.
This is the point that everybody except you seems to realise, it was an experiment that went wrong, with more development it would have been better, but it never got it, so in both engineering and commercial terms, it was a failure, that is beyond doubt, long before you came along with all your ridiculous theories and comparisons, we all knew that.
But thanks for the entertainment, some of the stuff you have posted has genuinely made me laugh out loud and I’ve learned a lot from those who do actually have factual knowledge as they attempt (in vain) to correct the nonsense that you post.
Sent from my SM-G950W using Tapatalk
newmercman:
So if I understand this correctly, the AEC design team sat down for tea and biscuits and decided to make a V8 engine to compete with a Scania 140, which was to be released to the market some years in the future.Or…
At the time the average power rating in heavy trucks was around the 180hp range and the motorway network was yet to exist.
The British road haulage industry was largely dominated by BRS, who were also supping tea over at Scammell and coming up with a replacement for their preferred choice of lorry, the Bristol. They settled on the Crusader, with a day cab and the Rolls Royce Eagle engine at 220hp as their Jack of all trades tractor unit.
Meanwhile in Southall the idiots at AEC decided not to build something that would blow the doors off the Scania that didn’t yet exist, no they decided to make an engine that would fit under the soon to be released Ergomatic cab, this made it necessary to be of a compact design, a relatively large capacity engine, but one that would take up less room under the low mounted Ergomatic cab than an inline 6 of similar capacity.
In order to achieve this and not infringe the copywrited bore and stroke dimensions of the ■■■■■■■ engine, they decided on an oversquare design, yes it would have to be high revving, but as the go to transmission of the time was a 6spd, that wouldn’t be a problem, quite the opposite in fact.
On the surface, a sound philosophy, creating a range of lorries, sharing the same cab, from a 4x2 16ton rigid and 24/28ton tractor unit, through 6x2, 6x4, 8x2 and 8x4 chassis to the tractor units in 4x2, 6x2 and 6x4 format, with options of an inline six and V8 engine. Pretty much a horse for every course, keep up with demands of existing customers and win some new ones.
Then a merger with Leyland and cash flow was serverly compromised, meaning the flaws that showed up during testing of the V8 were not addressed and the project was shelved. Until a message came down from above to put the unfinished project into production.
But it’s not ready said the idiots in Southall, don’t worry about that said the big wigs at BL, you won’t believe the balls up of the fixed head inline six we’re about to release, just get it built and we’ll sort it out as we go, the Standard Triumph purchase is killing us and we need a few quid in the bank.
We can’t said Southall, it’s a dog, it needs a lot more development and testing, it will be a disaster. Oh yes you can said BL, don’t worry about upsetting customers, where else are they going to buy lorries from? Atkinson and the other lot from Cheshire can’t get enough engines from Hugh Gardner and Rolls Royce are in cohorts with BRS and Scammell. What are the lorry men going to do? Buy lorries from the bloody Germans and the white flag wavers across the channel? Just get it done.
The rest as they say, is history…
Sent from my SM-G950W using Tapatalk
That is the crux of it. This was the V8 vehicle was to complement the range. Neatly sidestepped during every criticism of the engine and vehicle because it doesn’t fit with the argument, is what is made abundantly clear in the very first CM article, namely the torque capacity - roughly 600 lbft- of gearboxes commonly fitted to UK vehicles of the time. The choice at the time (1962) would have been the AEC’s own heavy duty gearbox, Leyland’s (241■■) HD 'box, Moss, David Brown and ZF all offering five or six speed 'boxes or in some cases 10 speed variants. The alternative which was on the option list being the SCG ( Leyland owned) planetary gearbox. By the time production commenced the close ratio Fuller 0600 series box was being fitted by other manufacturers - the clue to its torque capacity being in its name. AEC themselves did at a later date offer this as an option for the 760 powered Mandator, but notably not for the engine at its highest output rating. The only gearbox commonly fitted at the time with a higher torque rating was IIRC Fodens 12 speed which would have been an unlikely alliance.
So in 1962 while it might have been possible to have produced an engine which produced more torque, there was a good reason not to do so at that time. That option being left to the planned AV800 and the follow ups which never materialised.
Are we to conclude that the A2 heads cured the poor circulation/hot spots problem? Could it be that the flow restriction (causing the excessive water pump back pressure) was reduced with these heads? Must we await Mr. ERF to do some testing?
If the later blocks also helped with the above issues, combined with the raised header tank and high datum cab, then that is the cooling system sorted, is it not?
newmercman:
Carryfast, I don’t believe anybody has said that the AEC V8 was a success, neither in design or operation. It is a belief that it could, with further development, have been a success, after all, that’s what engineers do, they come up with methods to make things work, there are countless examples of engineering triumphs to prove this, take a Porsche 911 as an example, in its current form it’s said to be one of the best handling sports cars ever made and yet the whole concept of the 911 is flawed, an engine mounted behind the rear axle should be a recipe for disaster, yet thanks to engineering it is not.So with a bit of development and a few fundamental changes, there is no doubt that the V8 could have been engineered to overcome its faults, as we know, it never happened.
However, it did go into production and as such it’s part of history, that history has told us that when it was running right, it went like the clappers and was a huge leap forward in performance compared to the previous engines from AEC and many others.
This is the point that everybody except you seems to realise, it was an experiment that went wrong, with more development it would have been better, but it never got it, so in both engineering and commercial terms, it was a failure, that is beyond doubt, long before you came along with all your ridiculous theories and comparisons, we all knew that.
But thanks for the entertainment, some of the stuff you have posted has genuinely made me laugh out loud and I’ve learned a lot from those who do actually have factual knowledge as they attempt (in vain) to correct the nonsense that you post.
The point being that they couldn’t possibly have developed something with that crippled stroke length into something which could meet its original design aims of competing in the 300 hp + big power truck league.While they probably could have made it into something which might have worked in the 500’s intended design league.Thereby solving two problems at once.
Although that isn’t much help when AEC really needed that 3 VTG cabbed 15 litre Scania 140 competitor in CM’s pages before the 140 got there.
Which leaves the question why not ?.So far with only gingerfold attempting to answer the question with some totally irrelevant bollox concerning the V8’s original very early 1960’s design premise,in the requirement for a silly small capacity,short stroke V8,that had to fit under an equally silly obsolete and irrelevant BMC cab.
As for the over powered Volkswagen.As I said the relevant comparison here would be a Cosworth DFV powered Zodiac Mk4 used to tow a caravan and the resulting argument at the dealer where it was bought and Ford saying FFS let him return it and have all his money back just to avoid all the bad publicity and warranty payments.I can just imagine all the Ford fan boys saying what a brilliant idea it was at the time and would have worked with a bit of development. 
On that note how could it possibly have ‘gone like the clappers’ with around just 250 hp and around similar torque to the 690 compared to even the 8 v 71 powered Crusader with its around 800 lb/ft and 300 hp ?.IE with the exception of the tilt cab what was the point of the AEC V8 either v the Crusader V8 or the Scania 140 ? even if it could have been made to stay together at 250 hp max rating let alone its 300 + design aim ?.
For God’s sake man, do you not absorb anything you read. At the time of the testing there wasn’t a 140 Scania and if the DD powered Crusader existed it was only in Miltary spec. The V8 Mandator may have been the most powerful lorry on sale in Britain at the time, the only thing that came close was the Scania Vabis LB76.
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cav551:
That is the crux of it. This was the V8 vehicle was to complement the range. Neatly sidestepped during every criticism of the engine and vehicle because it doesn’t fit with the argument, is what is made abundantly clear in the very first CM article, namely the torque capacity - roughly 600 lbft- of gearboxes commonly fitted to UK vehicles of the time. The choice at the time (1962) would have been the AEC’s own heavy duty gearbox, Leyland’s (241■■) HD 'box, Moss, David Brown and ZF all offering five or six speed 'boxes or in some cases 10 speed variants. The alternative which was on the option list being the SCG ( Leyland owned) planetary gearbox. By the time production commenced the close ratio Fuller 0600 series box was being fitted by other manufacturers - the clue to its torque capacity being in its name. AEC themselves did at a later date offer this as an option for the 760 powered Mandator, but notably not for the engine at its highest output rating. The only gearbox commonly fitted at the time with a higher torque rating was IIRC Fodens 12 speed which would have been an unlikely alliance.So in 1962 while it might have been possible to have produced an engine which produced more torque, there was a good reason not to do so at that time. That option being left to the planned AV800 and the follow ups which never materialised.
The project was actually stopped when it was realised that the supposed BMC deal was off.It was only then later in the early-mid 1960’s ( '64 ? ) that the idea was resurrected with a design requirement for at least a 300 hp powered vehicle.So far so good.Assuming that Fuller couldn’t provide anything with more than a 600 lb/ft rating then what rating were they using in the 8v71 powered '65 KW as shown here ?.Bearing in mind that 12v71 Brockway 359’s weren’t unheard of by '66 either.
youtube.com/watch?v=huS1LPk7F2E
and what was Scammell using in the 8v71 powered Crusader.Number 1 off the line reportedly being an 8v71 powered 6x4 in '68 ?.
You really need to raise your sights here regarding what was available and when and whatever stopped AEC from putting a 320 hp,690 based,V8 in the 3VTG by '68-'69 it wasn’t because Fuller couldn’t have provided them with a box to handle it. 
coachbuilt.com/bui/b/brockway/brockway_2.htm
youtube.com/watch?v=pQnA6nsgZEo
newmercman:
For God’s sake man, do you not absorb anything you read. At the time of the testing there wasn’t a 140 Scania and if the DD powered Crusader existed it was only in Miltary spec. The V8 Mandator may have been the most powerful lorry on sale in Britain at the time, the only thing that came close was the Scania Vabis LB76.
Firstly we know that the 140 was on the drawing board by 1962.Why would there have been pre production prototypes in the case of the AEC but not the 140 with the 140 in production by '69 so as near the AEC as makes no difference.Also I might be wrong but if I’ve got it right military Crusaders were Rolls powered not 8v71 with an 8v71 version reportedly being number 1.The fact remaining that the AEC was never going to meet its 300 hp + spec with a BMEP figure of less than the 690 nor without risk of grenading with such a short stroke.While Scammell already obviously had as close as it got anyway so what was the point and why did they waste all the potential contained in the 3 VTG package in favour of the poxy Mandator and its silly predictably inferior motor ?.
[zb]
anorak:
Are we to conclude that the A2 heads cured the poor circulation/hot spots problem? Could it be that the flow restriction (causing the excessive water pump back pressure) was reduced with these heads? Must we await Mr. ERF to do some testing?If the later blocks also helped with the above issues, combined with the raised header tank and high datum cab, then that is the cooling system sorted, is it not?
I think the word would be ‘improved’.
The ‘A2’ heads certainly have modified water channels, but my engine has them and still suffers with the pressure and restriction, hence fitting wire reinforced hoses to the back of the block. Whether it would be worse with the old ‘A’ heads, I can’t say for certain as we didn’t ever test an engine with them fitted, but I would expect it would.
It’s very difficult to know for sure exactly what causes the poor coolant circulation in these engines, but when you study the path the coolant takes (with the thermostat open) from the bottom radiator hose, around the engine, and then back out the top hose it is incredibly convoluted. It is no real surprise that hot spots could develop in the block, particularly around No 4 cylinder, but to cure it would require a redesign of the entire block casting including the water pump location and the coolant path, something I am sure AEC had on the drawing board before the engine even went into production. This would be the only way to fully sort it. No amount of different cabs or larger header tanks would cure the compromised design, although certainly increasing the coolant capacity could only have helped.
ERF, you’re good and patient at digging for information, I have found a reference to AEC in “The Engineer” journal, dated 1968/05/24, but I haven’t found a means of accessing it. As that date is bang on coincidental with the launch of the Mandator V8, then it could be about the vehicle and engine. If it is it would be interesting to read that journal’s take on the V8.