martynv8
Well-Known Member
I am not talking large and small engines running at different RPMs for the same power output, with different gear ratios, different cars with different aerodynamics and body weights, of course there is a difference. I was talking a 4.0 litre Land rover V8 as opposed to a 4.6 litre Land rover V8. Same car, same weight, same frontal airflow resistance, same gear ratios. At any given RPM the 4.6 will use more fuel than the 4.0 litre. That is where the simples comes in. Land rover seem to agree with me, as the mileage figures for the 4.6 are marginally worse than those claimed for the 4.0 litre engine under all conditions. So your argument is out of the window i am afraid.
Unless i'm mistaken, the point being made (very simply put) is that even though the 4.6 will obviously use more fuel at the same RPM as a 4.0, the 4.6 under many circumstances needs less RPM.
I suspect real world figures would show little between them, but who cares, they are both thirsty petrols. The 4.6 having a gearbox that's actually up to the job & generally better trim levels won it for me.