To be clear, we would not know the optimum temperatures for the fuel and charged intake air of a 2014 engine from the RA168E.
In 1988, the only reason Honda pre-heated their fuel, and kept the charged intake air at 70*C for their RA168E was to help with fuel vaporization.
The factors controlling vaporization would include:
- The chemical composition of the fuel
- The fuel pressure at the injectors
- The design of the injectors
- The thermal environment inside the cylinder during intake and compression strokes
- The bore size, stroke length, and cylinder head design
So while it's not safe to assume that today's 2014 F1 engines require 70*C intake air, gruntguru is certainly right to show us the example of Honda finding that it's possible to lose efficiency by over-cooling the charged intake air of a turbo-charged engine. Thanks for that!
A snippet relating to this discussion, from Autosport.com today:
The Red Bull has also been seen without bodywork in the garage. The large size of the cooler package and in particular the turbo intercooler, which is split into two with one part in each sidepod, is immediately apparent. The intercooler is about four times the thickness of the radiators and far larger than other teams' set-ups. That suggests the Renault unit needs a far lower charge air temperature to make power reliably, which of course comes at the price of the aero penalty of larger sidepods.
And this, also from Autosport.com:
With the all-new power units being so different to each other this year, it's worth noting a design detail on the Mercedes engine. As far as we can see, the turbo installation on the Ferrari and Renault engines places the entire turbo low down behind the engine.
By contrast, the Mercedes turbo is split. The exhaust-driven turbine is still mounted behind the engine, but the larger compressor is mounted ahead of the engine. The two units are linked via a shaft passing through the 'V' of the engine, most likely with the MGU-H mounted between them. The placing of the large aluminium compressor at the front of the engine means it's far removed from the extreme 900 degrees C heat of the turbine, which will reduce charge air temperatures.
Edited by RogerGraham, 15 March 2014 - 12:52.