Preamble:
For the sake
of brevity and the time it’d take for the entire gamut to sink-in,
I’m splitting this Article into two parts.
Part-I deals with some basics and how the ‘condition’ of your
Car can affect the best possible results.
Part-II will deal with the ‘external’ factors that can turn
the tables – including you as the proverbial ‘Nut behind the
Wheel’!
For starters, let’s get some fundamentals cleared up first
–
i)
The 'Fuel-Efficiency' of an ICE is quoted in terms of 'Grams per Bhp per
hr'.
ii) On the other hand, the ‘Fuel Consumption’
of it is directly related to the ‘Bhp x hrs’ demanded from
it.
In general, it can also be safely stated that -
iii) A larger ‘CC’ Engine will have higher
internal frictional losses in terms of 'Bhp', though as a percentage of
its max Bhp capability it may be the same as compared to a smaller one.
iv) A larger CC Engine, therefore, would be desirable
to be fitted to a heavier and more 'wind resistant' a Car in absolute
terms. Thus to accelerate and cruise it similar to a smaller Car, it would
demand more ‘bhp’ from its engine.
v) It can, therefore, be surmised that the 'overall fuel
consumption’ of a larger engined/heavier Car would be higher as
compared to a smaller one - given the same ‘fuel-efficiency’
and operating conditions.
vi)
Given the Mandatory Compliance of all Automobile Engines in the Country
today with ‘EU-II’ Norms, it can be inferred that they are
all practically as ‘fuel-efficient’ as the other. However,
by increasing their ‘Volumetric-Efficiency’ with means such
as ‘multi-valve’ per cylinder – their ‘Bhp/CC’
quotient can be improved.
vii)
In other words, the same ‘CC’ Engine with 2-valves/Cyl when
upgraded to 4-valves/Cyl – read Esteem EU-I to EU-II – becomes
more ‘relaxed’ when producing the same Bhp and therefore,
consumes less fuel in the process. |
