One of my old school, eco power trains was the 1.6 carb in my 89 golf 'driver' - 4+E box (25mph/1krpm top cog) running a 38dtml weber and not much else I got 51mpg(imp) out of it cruising at 65 to and from Crewe. it may have had the aero of a barn door but it was it was one of the last true 'peoples cars' VW's. Built cheaply but built right - before they got all middle class after german re-unification
designed to ferry kids'n'crap from one end of Deutchland to the other quietly and simply
no real gimmicks to the engine just torque with LONG gearing and it was sub 1000kg in weight. oh and they had the suspension off a GTi to help 'keep up momentum' on the twisty bits.
loved the A-series in my minis, think the PSA group's 1.4 tu engine deserve a mention too except for when mated to the 4 speed wand gearbox in a 205 where you chased the cogs around the floor and third would be in a different place everytime you looked for it.
OH - and the unburstable nissan micra 16v engines of the mid nineties - especially the 1.0 that will rev to 8k (witnessed it) and when driven normally will easily average 55mpg even though its an SPi I think? don't quote me. they're still in production even though they have evolved slightly
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good things come to those who wait, sh*t turns up pretty much instantly
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