Well stroke me! 
Isn’t that Gillian Duxbury?
[zb]
anorak:Carryfast:
ramone:
You keep refering to TL12s as junk but you have no figuresWhich part of you ultimately need 43% more specific torque from 7% less leverage and 5% more piston area didn’t you understand.
The Volvo TD120 had a stroke of 150mm, versus the TL12’s 142mm. Not a great difference. The TD120 had a 920lbft peak torque figure, which is a greater advantage. The difference can only be due to higher turbocharger pressure. In other words, the Volvo engine had higher combustion loads, despite a smaller bore. That is the difference, little to do with the bore/stroke ratio- the Volvo was simply more advanced, in terms of torque per litre. It was also more advanced than Scania’s DS14, in the same regard. The moral of the tale is that bore/stroke ratio was not a driving variable in the 1970s.
Of course, 50 years later, combustion pressures are much higher, and rated speeds are lower. Engines are a different shape, as a result. Only an idiot would denigrate the work of the engineers half a century ago, based on half a century of change. That’s my last sensible word on this thread. Subsequent posts will be silly.
Only an idiot, or more like working under orders from above along the lines of our 7.5 t bus engine block will also just have to do for our 32-38t truck engine block, would ignore the role of the stroke ( leverage ) side of the equation in determining the specific torque output.
Either more of it for the equivalent force applied to the piston or less force needed for the equivalent output.
The Volvo’s leverage advantage still outweighed the TL12’s piston area advantage.Why would it have needed higher cylinder pressures for equivalent specific torque output ?.
While the total difference in leverage still applies to end bearing loads.You seem to have conveniently missed the output of the TD120 FC introduced in 1981 1,140 lbft not 920.
So 38% more specific torque with 5.6 % less leverage and 4.6 more piston area = 38% x 5.6% more end bearing loads and 38% x 1% more cylinder pressure ■■.
That’s why the TL12 had to be taken out of service 10 years after its introduction.
Unlike the Eagle and TD120.
Wheel Nut:
Sent from my iPhone using Tapatalk
Typical British Leyland. Couldn’t even be bothered to find a pair of shorts that fitted her.
Wheel Nut:
A Dutch honey trap.All part of the conspiracy.They told her that 142 mm was the same thing as 6 inches and she didn’t understand metric measurements. 
[zb]
anorak:Wheel Nut:
Sent from my iPhone using Tapatalk
Typical British Leyland. Couldn’t even be bothered to find a pair of shorts that fitted her.
Ooo I don’t know!
Certainly would not get away with ads like that today.
[zb]
anorak:
Typical British Leyland. Couldn’t even be bothered to find a pair of shorts that fitted her.
To be fair in that case less = more.
Stokes is bound to get the blame for it.
The Swedes obviously missed an opportunity to get into an advertising war with Leyland.
Carryfast:
[zb]
anorak:Carryfast:
ramone:
You keep refering to TL12s as junk but you have no figuresWhich part of you ultimately need 43% more specific torque from 7% less leverage and 5% more piston area didn’t you understand.
The Volvo TD120 had a stroke of 150mm, versus the TL12’s 142mm. Not a great difference. The TD120 had a 920lbft peak torque figure, which is a greater advantage. The difference can only be due to higher turbocharger pressure. In other words, the Volvo engine had higher combustion loads, despite a smaller bore. That is the difference, little to do with the bore/stroke ratio- the Volvo was simply more advanced, in terms of torque per litre. It was also more advanced than Scania’s DS14, in the same regard. The moral of the tale is that bore/stroke ratio was not a driving variable in the 1970s.
Of course, 50 years later, combustion pressures are much higher, and rated speeds are lower. Engines are a different shape, as a result. Only an idiot would denigrate the work of the engineers half a century ago, based on half a century of change. That’s my last sensible word on this thread. Subsequent posts will be silly.
Only an idiot, or more like working under orders from above along the lines of our 7.5 t bus engine block will also just have to do for our 32-38t truck engine block, would ignore the role of the stroke ( leverage ) side of the equation in determining the specific torque output.
Either more of it for the equivalent force applied to the piston or less force needed for the equivalent output.The Volvo’s leverage advantage still outweighed the TL12’s piston area advantage.Why would it have needed higher cylinder pressures for equivalent specific torque output ?.
While the total difference in leverage still applies to end bearing loads.You seem to have conveniently missed the output of the TD120 FC introduced in 1981 1,140 lbft not 920.So 38% more specific torque with 5.6 % less leverage and 4.6 more piston area = 38% x 5.6% more end bearing loads and 38% x 1% more cylinder pressure ■■.
That’s why the TL12 had to be taken out of service 10 years after its introduction.
Unlike the Eagle and TD120.
So on your theory , i cant undo this tight nut i need a much longer spanner , oh this is 8mm longer that should do the trick , i cant understand how all these highly experienced engineers got it so wrong when all they needed to do was nip down to their local fire engine builder and ask the sweeper upper
Excellent ramone 
cheers Ray
ramone:
Carryfast:
Only an idiot, or more like working under orders from above along the lines of our 7.5 t bus engine block will also just have to do for our 32-38t truck engine block, would ignore the role of the stroke ( leverage ) side of the equation in determining the specific torque output.
Either more of it for the equivalent force applied to the piston or less force needed for the equivalent output.The Volvo’s leverage advantage still outweighed the TL12’s piston area advantage.Why would it have needed higher cylinder pressures for equivalent specific torque output ?.
While the total difference in leverage still applies to end bearing loads.You seem to have conveniently missed the output of the TD120 FC introduced in 1981 1,140 lbft not 920.So 38% more specific torque with 5.6 % less leverage and 4.6 more piston area = 38% x 5.6% more end bearing loads and 38% x 1% more cylinder pressure ■■.
That’s why the TL12 had to be taken out of service 10 years after its introduction.
Unlike the Eagle and TD120.
So on your theory , i cant undo this tight nut i need a much longer spanner , oh this is 8mm longer that should do the trick , i cant understand how all these highly experienced engineers got it so wrong when all they needed to do was nip down to their local fire engine builder and ask the sweeper upper
8mm longer spanner x 6 of em which have to create almost 200 lbft each during just the power stroke of every other revolution of the engine at around 1,200 rpm.I’ve provided the resulting difference in the figures that just that 8-10mm makes to head fastening and end bearing loads.Those figures are scary because the seemingly small 8-10mm deficit is a multiplying constant within the force x distance equation in which the force figure is massive and it’s why there was never a 320 let alone 400 TL12 with almost 100 lbft per litre.
Not exactly the sweeper upper.
But luckily also not a bus manufacturer with no buses to sell because it decided to stop making buses, which it was bleedin good at.
Which thought no problem we’ll just use the same bus engine design in 32t trucks.What could possibly go wrong.
Not that it made much difference because first they took out AEC then they took out us and Bedford and Scammell and Rover and Triumph all as part of the plan to make Europe and especially Germany great again.
Carryfast:
ramone:
Carryfast:
Only an idiot, or more like working under orders from above along the lines of our 7.5 t bus engine block will also just have to do for our 32-38t truck engine block, would ignore the role of the stroke ( leverage ) side of the equation in determining the specific torque output.
Either more of it for the equivalent force applied to the piston or less force needed for the equivalent output.The Volvo’s leverage advantage still outweighed the TL12’s piston area advantage.Why would it have needed higher cylinder pressures for equivalent specific torque output ?.
While the total difference in leverage still applies to end bearing loads.You seem to have conveniently missed the output of the TD120 FC introduced in 1981 1,140 lbft not 920.So 38% more specific torque with 5.6 % less leverage and 4.6 more piston area = 38% x 5.6% more end bearing loads and 38% x 1% more cylinder pressure ■■.
That’s why the TL12 had to be taken out of service 10 years after its introduction.
Unlike the Eagle and TD120.
So on your theory , i cant undo this tight nut i need a much longer spanner , oh this is 8mm longer that should do the trick , i cant understand how all these highly experienced engineers got it so wrong when all they needed to do was nip down to their local fire engine builder and ask the sweeper upper
8mm longer spanner x 6 of em which have to create almost 200 lbft each during just the power stroke of every other revolution of the engine at around 1,200 rpm.I’ve provided the resulting difference in the figures that just that 8-10mm makes to head fastening and end bearing loads.Those figures are scary because the seemingly small 8-10mm deficit is a multiplying constant within the force x distance equation in which the force figure is massive and it’s why there was never a 320 let alone 400 TL12 with almost 100 lbft per litre.
Not exactly the sweeper upper.
But luckily also not a bus manufacturer with no buses to sell because it decided to stop making buses, which it was bleedin good at.
Which thought no problem we’ll just use the same bus engine design in 32t trucks.What could possibly go wrong.
Not that it made much difference because first they took out AEC then they took out us and Bedford and Scammell and Rover and Triumph all as part of the plan to make Europe and especially Germany great again.
I think your leverage theory is utter BS .because it would only be 48 mm overall and would make no difference
Carryfast:
ramone:
Carryfast:
Only an idiot, or more like working under orders from above along the lines of our 7.5 t bus engine block will also just have to do for our 32-38t truck engine block, would ignore the role of the stroke ( leverage ) side of the equation in determining the specific torque output.
Either more of it for the equivalent force applied to the piston or less force needed for the equivalent output.The Volvo’s leverage advantage still outweighed the TL12’s piston area advantage.Why would it have needed higher cylinder pressures for equivalent specific torque output ?.
While the total difference in leverage still applies to end bearing loads.You seem to have conveniently missed the output of the TD120 FC introduced in 1981 1,140 lbft not 920.So 38% more specific torque with 5.6 % less leverage and 4.6 more piston area = 38% x 5.6% more end bearing loads and 38% x 1% more cylinder pressure ■■.
That’s why the TL12 had to be taken out of service 10 years after its introduction.
Unlike the Eagle and TD120.
So on your theory , i cant undo this tight nut i need a much longer spanner , oh this is 8mm longer that should do the trick , i cant understand how all these highly experienced engineers got it so wrong when all they needed to do was nip down to their local fire engine builder and ask the sweeper upper
8mm longer spanner x 6 of em which have to create almost 200 lbft each during just the power stroke of every other revolution of the engine at around 1,200 rpm.I’ve provided the resulting difference in the figures that just that 8-10mm makes to head fastening and end bearing loads.Those figures are scary because the seemingly small 8-10mm deficit is a multiplying constant within the force x distance equation in which the force figure is massive and it’s why there was never a 320 let alone 400 TL12 with almost 100 lbft per litre.
Not exactly the sweeper upper.
But luckily also not a bus manufacturer with no buses to sell because it decided to stop making buses, which it was bleedin good at.
Which thought no problem we’ll just use the same bus engine design in 32t trucks.What could possibly go wrong.
Not that it made much difference because first they took out AEC then they took out us and Bedford and Scammell and Rover and Triumph all as part of the plan to make Europe and especially Germany great again.
I am not an engineer so can’t comment on the specific design limitations of the TL 12. I make an assumption that the engine was taken as far as it could go as by that time there would be insufficient funds to develop a completely new engine design. They {the engineers} took the best they had and did the best they could with it. Why did the Leyland group have insufficient funds to develop a new engine? Well there is plenty of information on this thread and the rest of the forum that explains that apart from the damage BMC side did to finances the truck side had 2 engines disasters in a short space of time. Why were those disasters allowed to happen? The buck ultimately must stop with the top management.
ramone:
I think your leverage theory is utter BS .because it would only be 48 mm overall and would make no difference
Which part of the all force acting on the piston and con rod assembly and head fastenings ( which is bleedin massive as in tens of tonnes per square inch ) reduced by 7% in the case of RR v TL12 for the equivalent torque output don’t you understand.
It’s not a theory it’s why the MX 13 has a bore stroke ratio of 0.80 as opposed to the DK’s 0.89.
Contrary to anorak’s bs it’s done to ‘reduce’ cylinder and piston/road assembly pressures for an equivalent specific torque output because as I said it’s a force multiplier based on the laws of leverage.
essexpete:
I am not an engineer so can’t comment on the specific design limitations of the TL 12. I make an assumption that the engine was taken as far as it could go as by that time there would be insufficient funds to develop a completely new engine design. They {the engineers} took the best they had and did the best they could with it. Why did the Leyland group have insufficient funds to develop a new engine? Well there is plenty of information on this thread and the rest of the forum that explains that apart from the damage BMC side did to finances the truck side had 2 engines disasters in a short space of time. Why were those disasters allowed to happen? The buck ultimately must stop with the top management.
They didn’t need a ‘new engine’.The Eagle had everything they ‘needed’ from a true 290 capability at the T45’s launch and nearer to 350 in 1984, up to 400 hp potential at which rating it was better on fuel than the DAF 400.
It was just a matter of handing over one state owned asset to another no fee required.
The government was Leyland’s ‘top management’.The government were working to a plan of making Europe great again after Germany had smashed its economy including its own.
Carryfast:
ramone:
I think your leverage theory is utter BS .because it would only be 48 mm overall and would make no difference…Contrary to anorak’s bs …
Everything I have said on this thread is simple fact, which may be checked against common knowledge, or deduced using schoolboy maths.
[zb]
anorak:
Everything I have said on this thread is simple fact, which may be checked against common knowledge, or deduced using schoolboy maths.
Tell us why more leverage supposedly means higher cylinder pressures for equivalent specific torque output.
As opposed to the exact opposite assuming a net piston area deficit v leverage.
Although I didn’t see you argue with any of my figures.You know like 7% more leverage means a corresponding 7% reduction in the massive forces required on end bearings for the equivalent specific torque output.
Also reduction in loads on cylinder head fastenings proportional with any piston area deficit v leverage advantage.
Feel free to try it bearing in mind that you seemed to have backed off the bs 2 x BMEP figure regarding those ‘forces’.
Anorak while respecting all you and other contributors with accurate information he’ll always be right you’re ■■■■■■■ against a force 9 gale the reason I’m following this is i was interested in the Leyland buffalo thread then he came in with all his anti British leyland claptrap cheers Ray 
stargazer148:
Anorak while respecting all you and other contributors with accurate information he’ll always be right you’re ■■■■■■■ against a force 9 gale the reason I’m following this is i was interested in the Leyland buffalo thread then he came in with all his claptrap cheers Ray
So exactly what is wrong with my figures and what did anorak’s figure of 2 x BMEP mean and refer to.
7% reduction in ‘a lot’ of force by multiplying it with more leverage, required to create the Equivalent BMEP, is a lot
You’re ‘following this’ to just moan and contribute nothing.
Carryfast:
ramone:
I think your leverage theory is utter BS .because it would only be 48 mm overall and would make no differenceWhich part of the all force acting on the piston and con rod assembly and head fastenings ( which is bleedin massive as in tens of tonnes per square inch ) reduced by 7% in the case of RR v TL12 for the equivalent torque output don’t you understand.
It’s not a theory it’s why the MX 13 has a bore stroke ratio of 0.80 as opposed to the DK’s 0.89.Contrary to anorak’s bs it’s done to ‘reduce’ cylinder and piston/road assembly pressures for an equivalent specific torque output because as I said it’s a force multiplier based on the laws of leverage.
140 divided by 152 equals what? and who made an engine with those dimensions? they must have been idiots too in your opinion then?
Which other manufacturer produced an engine which was so bad that it resulted in a class action in North America?
I’ll give you a clue: one you are keeping a bit quiet about and the other you have started championing.
Carryfast:
essexpete:
I am not an engineer so can’t comment on the specific design limitations of the TL 12. I make an assumption that the engine was taken as far as it could go as by that time there would be insufficient funds to develop a completely new engine design. They {the engineers} took the best they had and did the best they could with it. Why did the Leyland group have insufficient funds to develop a new engine? Well there is plenty of information on this thread and the rest of the forum that explains that apart from the damage BMC side did to finances the truck side had 2 engines disasters in a short space of time. Why were those disasters allowed to happen? The buck ultimately must stop with the top management.They didn’t need a ‘new engine’.The Eagle had everything they ‘needed’ from a true 290 capability at the T45’s launch and nearer to 350 in 1984, up to 400 hp potential at which rating it was better on fuel than the DAF 400.
It was just a matter of handing over one state owned asset to another no fee required.The government was Leyland’s ‘top management’.The government were working to a plan of making Europe great again after Germany had smashed its economy including its own.
Which particular government are you referring to?