I would have to ditto the mileage on the red engine. It was always fairly
good considering the size of the car. Yeah you _can_ get better mileage by
thinning the mixture till the head glows, or running a higher compression
with a smaller engine and winding it up further or cutting the tin out and
running skinny tires.
Or you can tweak the gearing, or you can use more modern drivetrain
management, or you can design the car to be more aerodynamic, and so on,
and so forth. Everything's a tradeoff, but not all tradeoffs are equal.
If you're leaning the mixture to the point that the head(!) is glowing,
you're way past peak efficiency. Similarly, an overly rich mixture will
do wonders for overheating your catalytic converter and possibly washing
the oil off of the cylinder walls, increasing engine wear.
As was pointed out, a Camry is of a similar power to weight ratio as a
240. Yet, the four banger Camry will handily get significantly better
mileage than a 240. There are a few things working in the Camry's favour.
At legal highway speeds, my friend's 87 Camry was turning under 2000 RPM.
Try that with a 240. Similarly, the Camry also had a lockup torque
conveter, something that a 240 never got (yet a lockup transmission is
hardly new, exotic, delicate, or complicated).
If you do that you increase your depency on electronics to manage all
that crap, increase the wear on the internal parts causing shorter total
engine life, and have a car that you can't drive confidently in hard
city driving. A Volvo would make a good taxicab, a camry would make a
good recycled pepsi-can under the same driving conditions.
They use Camrys as taxis out here (California, home to some of the
shittiest roads ever built). If you've got such a fear of electronics,
why are you driving a 240? You realize that 240s in the US all have
electronic ignitions, most have electronic idle control, and most have
electronic fuel injection? If what you say is true, we should see a whole
lot more 140s on the road than 240s.
Let's not forget that Volvo switched to electronic speedometers in the US
(in 86) well before many other companies. Yet, the real speedometer
problems were mechanical (with the odometer gears breaking and such).
The 240 is/was just one of the most balanced systems ever put into sheet
metal. Everything went together so that the car was just right. Not
sporty, or luxury, but right.
Hardly. If that were true, IPD wouldn't make a killing selling upgraded
anti-sway bars to handle the pretty lousy stock suspension setup.
I think the real problem is that most people are waving their hands in
despair... fretting over these newfangled 850s. When in reality, you're
seeing more and more high mileage 850s on the road, in pretty darn good
shape, getting much better fuel economy out of a similar sized engine to
boot.
Did I mention that a non-turbo 850 has a similar power to weight ratio as
a 700/900 series turbo?