Well I for one don't believe you got 36 mpg as a measured tank top to tank top mpg that just happened to match your dash readout after 9 miles...thats like double the mpg most get....no amount of extra cooling is going to improve it that much....in fact generally, on lots of engines, the hotter it runs (without over heating of course)the greater the efficiency ....but I can't prove it...so there you go...so it must be true and I must be wrong.
Yes you are! This, or specifically my 159, before modifying, ran hot. An over hot engine will misfire - evidence of misfires abound on this site. And coil packs melt, not because of heat, but over - current!!!!! Yet the ECU and or the coil pack drivers remain undamaged????
True, engines have to run at an optimum for best efficiency. But the margin for optimum temperature is quite tight.
This engine is direct injection and at a compression ratio unseen in previous generations of production Alfa’s. They get away with it, principally, but not entirely, because the air charge (fuel free) contributes greatly to engine/upper cylinder cooling.
But also depends very much on exhausting the spent burn swiftly. That function is performed by the VVT action on the exhaust camshafts. Early opening on warm up/pre light off, shifting quickly to late opening when under power.
The figures I have given were witnessed. But it of no consequence to you as you are never going to buy a 3.2 JTS, or a 1750 TBi.
The real point about the improvements I have made are not about making the engine any more powerful, just recovering more inherent losses, such that they appear as motive force and not as heat.
The density of the air charge, or for that matter, with inlet manifold injection, mixture, greatly effects the power output. Why else would cold charge manifolds be so much in vogue? Does not every car run better at sea level than at 5000 feet?
Ask anyone who runs an Alfa in Johannesburg then in Cape Town. One character had a Busso powered racer - rear mounted with a Porsche transaxle doing 600 in J/Burg but 750 in Cape Town.
Volumetric efficiency is very much dependent upon the density of the cylinder charge. There are plenty of charts and scientific articles to be viewed on the web which illustrate the effect of over - temperature on the specific power output of an engine.
Well worth looking up if indeed you are that interested.