Datatek
Well-Known Member
Before manadatory cats, Ford ran fuel air ratio's of up to 21 to 1 and 17 to 1 was not uncommon.Difference here is i know what i'm talking about and you don't. You obviously still do not understand the required mixture ratio needed in petrol engines for clean efficient burn. A larger cylinder has more air in it at any given time and therefore needs more fuel than a smaller cylinder would under the same conditions, simple as that. Is that so hard to follow? We know the difference in the 4.0 and 4.6 engine is only 600 cc that is why the difference in fuel used is comparatively small as well explained by Ant. By your reasoning if they increase the 4.6 to 5.0 litres and give it more torque maybe it could beat the consumption figures of the 4.0 litre engine. It simply does not work that way. In general terms the larger the engine the more fuel it needs.
Folowing your logic, it would never have been possible to get the improvements in economy that have been achieved by better control of fuelling, the same amount of bang is being achieved from considerably less fuel these days.
As for the antique LR V8 I can't see there would be much difference between to two engine except the longer stroke and increased torque should make it a more relaxed drive. I would guess there is a bigger difference in consumption between Gems and Thor and that could answer whay the 4.6 appears better than some 4.0's.