The DD made a lot of noise but didn’t get far, at least the ■■■■■■■ got down the road.
newmercman:
The DD made a lot of noise but didn’t get far, at least the ■■■■■■■ got down the road.
To be fair I think that was more about making as much noise as possible not going as fast as possible.Although it didn’t seem to say exactly which spec it was.From memory I think the VT903 was all out at around 350 hp as usual for the design at silly revs at least in civilian haulage spec.While that would have been a very low rating for the 8V92.
I prefer the rumble of the ■■■■■■■ to the scream of the Detroit, but having had a V8 with straight pipes, I am bloody glad I’m not sat on top of one any more, a beautiful noise, no doubt about that, but you can definitely have too much of a good thing as my tinnitus proves 
Hey, there was a time it went with 150hp and only 5 or 6 speeds, in the motorway area 200 and 8 speeds could hold you at 90kph loaded without wind and on flat way.
About the Fiat or Unic engine it was a good one with a short stroke but needed revs till it got a turbo on it.
A short stroke engine is for a race car, in trucks it only allowed more power with more cylinders and revs, but without turbo knowledge it was a solution. As did MB for a long time and a good solution, because all other German manufactures trying to power their engines with turbos has known a lot of difficulties.
For all it is or was a challenge to make a good V engine.
So of all, the best thing is a 6 in line, less wear, less parts and easier to work on.
Even MB with its rather young V engines moves to 6 in line, MAN the same, when will Scania do ■■?
The MB engine is heavier as the V but MAN’s is lighter as the V engine, but don’t think that weight is critical
at such big power trucks.
my opinion.
Bye Eric,
tiptop495:
Hey, there was a time it went with 150hp and only 5 or 6 speeds, in the motorway area 200 and 8 speeds could hold you at 90kph loaded without wind and on flat way.
About the Fiat or Unic engine it was a good one with a short stroke but needed revs till it got a turbo on it.
A short stroke engine is for a race car, in trucks it only allowed more power with more cylinders and revs, but without turbo knowledge it was a solution. As did MB for a long time and a good solution, because all other German manufactures trying to power their engines with turbos has known a lot of difficulties.
For all it is or was a challenge to make a good V engine.
So of all, the best thing is a 6 in line, less wear, less parts and easier to work on.
Even MB with its rather young V engines moves to 6 in line, MAN the same, when will Scania do ■■?
The MB engine is heavier as the V but MAN’s is lighter as the V engine, but don’t think that weight is critical
at such big power trucks.
my opinion.Bye Eric,
Ironically even in the case of the ultimate output race type engines,it’s still the idea of putting the priority on the stroke measurement that’s relied on more than putting it on the bore.For the usual reasons of minimising stress levels in the piston to crank componentry link for the most output.
As for the inline 6 as opposed to the V8 type choice,it’s obvious that the inline 6 cylinder design has the advantage in providing the best all round combination of cost,efficiency, output,durability,maintenance and customer acceptance.While the big V8 ( or 12 ) can provide a better combination of ultimate outputs and durability ‘if’ compromises aren’t made in regards to overall capacity limits,stroke measurements and therefore relative engine speeds.
Unfortunately in this case AEC seems to have forgotten all that in having not only made the worst type of choice of V8 design possible,But arguably made the even bigger mistake of having gone along the V8 route when it needed to be sorting out a decent inline 6 cylinder product.Thereby resulting in splitting what limited resources that it had available. 
newmercman:
I prefer the rumble of the ■■■■■■■ to the scream of the Detroit, but having had a V8 with straight pipes, I am bloody glad I’m not sat on top of one any more, a beautiful noise, no doubt about that, but you can definitely have too much of a good thing as my tinnitus proves
^ +1.While the howl of an engine firing at high frequency is always interesting.It’s the even low frequency beat of 6 or 12 cylinders running at relatively low revs which is probably best to live with every day.Or maybe I’m just getting old. 
newmercman:
So the stroke measurement would always be a compromise then, but still I bet that 3000rpm V8 would sound good through a nice free flowing exhaust system.
I don’t see why a short stroke is a compromise- the torque is proportional to the product of the area of the bore multiplied by the stroke. Increasing one at the expense of the other does not alter the performance of the engine, but the short stroke engine is shorter overall, and is capable of higher speeds, due to the centrifugal acceleration at the big end. What is the most common “blow-up” scenario? I would guess that it is a rod coming through the side of the block. Fatigue failure of the rod is a function of the peak tensile stress in the rod, which is proportional to the mass of the piston multiplied by the acceleration of the piston at TDC. OK, there is a trade-off there, in that a bigger bore will entail a heavier piston but, all things considered, a shorter stroke allows higher speeds and a bigger bore allows bigger valves, which admit more air, which means more torque. In the early sixties, before turbochargers became trusted, speed was good. Between 1960 and 1970, the speed of lorry engines, at peak power, increased from around 2200rpm to 2500rpm, across Europe. They were all at it. If one maker could have made one of this new type of engine smaller in size than the 1950s-type, slow-running 6-in-line, it would have been ideal for the small-cab British market. It was not beyond the abilities of the engineers of the day, as Unic and Fiat proved.
If noise is your thing (who does not like noise?), have a look at the Ford D-series thread- the last versions of the ■■■■■■■ Vale V8 were said to be capable of running at 4500rpm for a 5 minute period, without damage.
I read that about the D Series, interesting, I imagine the manifold was probably a bit too warm for heating at your pie at those rpms
[zb]
anorak:newmercman:
So the stroke measurement would always be a compromise then, but still I bet that 3000rpm V8 would sound good through a nice free flowing exhaust system.I don’t see why a short stroke is a compromise- the torque is proportional to the product of the area of the bore multiplied by the stroke. Increasing one at the expense of the other does not alter the performance of the engine, but the short stroke engine is shorter overall, and is capable of higher speeds, due to the centrifugal acceleration at the big end. What is the most common “blow-up” scenario? I would guess that it is a rod coming through the side of the block. Fatigue failure of the rod is a function of the peak tensile stress in the rod, which is proportional to the mass of the piston multiplied by the acceleration of the piston at TDC. OK, there is a trade-off there, in that a bigger bore will entail a heavier piston but, all things considered, a shorter stroke allows higher speeds and a bigger bore allows bigger valves, which admit more air, which means more torque.
I think the analogy would be that your hands,wrists,arms,shoulders and back will all ache a lot more and/or possibly fail at any or all of those points if you try to shift a heavy load using a too short lever than if you use the longest one possible.
Especially in the case of trying to wind a truck up a hill using a too short stroke starting handle. 
Trying to sell an engine that develops hp at such high rpm removes a large section of the “loose” engine market from the equation.
Gensets run at around 1600rpm and must have fast recovery. I realise the variable frequency generator concept is now around, but big power producers still prefer the stable rpm design.
Also marine propulsion. No one can stand a high revving marine engine for too long.
Swapping a worn out slogger with a high revver immediately means gearbox ratio changes and prop/pitch changes. You’d have to weigh those extra costs up carefully.
Were there ever anyone who wanted to take AEC from Leyland , or was it a case of Leyland wouldn`t sell even if there were.?
ramone:
Were there ever anyone who wanted to take AEC from Leyland , or was it a case of Leyland wouldn`t sell even if there were.?
Ramone,Frank Zetters who was garage manager at A E Evans Barking depot and Len Shardlow his counterpart at Sheffield would have bought AEC off Leyland if they’d had the cash.They both said the writing was on the wall,AEC was doomed. Not sure if AEC was ever offered for sale by Leyland.
Chris Webb:
ramone:
Were there ever anyone who wanted to take AEC from Leyland , or was it a case of Leyland wouldn`t sell even if there were.?
Ramone,Frank Zetters who was garage manager at A E Evans Barking depot and Len Shardlow his counterpart at Sheffield would have bought AEC off Leyland if they’d had the cash.They both said the writing was on the wall,AEC was doomed. Not sure if AEC was ever offered for sale by Leyland.
I suppose from a competitors point of view it was the best solution ,another manufacturer out of the way ,no point in buying them to shut `em down just leave it to Leyland to ruin them
Evening all, it was tipical of british leyland to get ride of the best products AEC which in my experience of runing them they were far better than the rest in the group.We ran mandators for many years and when the V8 came out the rep at tillotsons in bradford Peter Lobley would not sell us one until they were developed properly,but as we all know that never happened.they did go well though far better than the 760,if they had been sorted out and as reliable as the760 they would have had a motor equal to any of the european stuff.
Cheer,s Richard.
I have absolutely no clue on what type of AEC the picture shows. What I do know is that the picture
is from 1956 and the operator is related to Kemper-Van Twist, importers of AEC and Perkins also
assemblers of the Seddon-VanTwist. Probably the trailer is from Ploeg, later known as PACTON.
Thank you for posting this photo. It is an AEC Mammoth Major 6 Mk.III with locally built cab.
Carryfast:
ramone:
Not entirely accurate but not far offIt ‘would’ be all but spot on ‘if’ only everyone would stop blaming Leyland’s management for the failings of AEC’s designers in the basic design of the thing.While realising that financial limitations on British industry meant that there was never going to be any second chances to get it right.Getting it right in this case meaning a totally different engine with a totally different much longer stroke measurement amongst other obvious architectural shortcoming improvements.In which case how many buyers would then have bought the resulting big power Scania 140 competitor.Even if by some miracle the money could have been found for the required engine upgrades let alone a competitive cab design to go with it.
The fact is the AEC V8 was an example of the job needing to be done right first time no ifs no buts but it’s designers let it down even before it had even left the drawing board.Even if they hadn’t the ‘real’ problems would have been then making the right truck to put it in let alone finding enough customers for it when they’d done it.Putting the blame for all that on Stokes won’t change those facts.
Good point , maybe if they made one one with a double dyper spring valve retraction plunger they might be still about today , simply they all got left behind , end ov
That is an AEC Majestic, basically a bonneted Mammoth Major 6 that spanned the Mk.111 and Mk.V era. It would probably have been fitted with an 11.3 litre engine. This and the four-wheeler version (Mogul) were export market models.
gingerfold:
That is an AEC Majestic, basically a bonneted Mammoth Major 6 that spanned the Mk.111 and Mk.V era. It would probably have been fitted with an 11.3 litre engine. This and the four-wheeler version (Mogul) were export market models.
Thanks for that. I must say lives up to its name, standing there under the palms! Robert