ERF:
Carryfast:
In which case even by those {torque} figures if piston area is worth more than leverage the difference between the Perkins v AEC would be expected to be a lot closer to the difference in bore size ( well over 20% ) than just 16%. {torque}In just that one statement you demonstrate your complete lack of understanding for Diesel engine dynamics.
To help with your maths again - 108 mm to 130 mm is 20.37%.
Is that “well over 20%” in your world?.Carryfast:
The obvious question then is what was the difference which made the Eagle able to stand up to going way past 100 lb/ft per litre but the AEC V8 failing at less than half that ?.That question has been answered in detail so many times over these pages.
I really do give up now…
I was going by the 13.1 litre engine’s 135 mm bore and 638 lb/ft AU 141 1967 figure ‘including’ any test standards differences. 
Apologies if I’ve confused that with the 12.1 litre 580 lb/ft figure although even that conparison is still more than a 20 % difference in bore size regardless.
While no the question as to how you’re going to increase,the AEC V8’s torque output,without breaking it,hasn’t been answered because it can’t be answered.With development and production of it predictably and unarguably having stalled then halted at 638 lb/ft and less than 50 lb/ft per litre to AU 141 1967 standard.
With the Rolls Eagle only going ever upwards from that figure including AU 141 1971.As for the Scania V8’s output with just a 127 mm bore don’t even go there.