F1 – 2014 the new era
Setting aside the Yuletide festivities for yet another year, Formula One teams will now be looking towards the 2013 season and the first test session at Jerez in February. During the next couple of weeks therefore, for engine suppliers this will mean final assembly and sign-off of dyno testing of the last of the 2.4 litre V8s, since come 2014 a totally new power unit design is to be unleashed. With its new-found wish to ‘assist’ the wider automotive industry, V8 engines apparently are no longer of any relevance, and like the mainstream passenger car business, engine downsizing accompanied by turbocharging is the key.
Thus the new engine regulations for 2014 specify 1.6 litre turbocharged V6 engines and, unlike many other turbocharged formulae, engine performance will not be limited by the inlet manifold ‘boost’ pressure but rather indirectly by the fuel flow rate, according to the formula Q (the flow rate in kg/h) = 0.009 x N (engine speed in rpm) + 5. This, it is stated, will encourage engine designers to extract every last bhp out of the fuel allowed at all engine speeds, and by so doing add to the general pool of knowledge available to the roadcar engine designer. With no maximum intake manifold pressure set as such, and for overall engine fuel efficiency, it is expected therefore that engines will be only mildly boosted to something around 2-3 bar.
Fuel efficiency, however, means different things to the road engine designer than the race engine designer. The former concentrates mainly on the specific legislative test cycles used to determine the engine tailpipe emissions of unburned hydrocarbons, carbon monoxide, oxides of nitrogen and of course carbon dioxide, which these days seems to the villain in the story. At these conditions, engines will be running almost totally under low-speed, part-throttle conditions, where the mechanical friction is low and the advantages of direct injection – better, more precise control over the combustion and the lack of wall wetting in the intake port zone – are undisputed.
By their very nature though, race engines run more towards the wide-open throttle envelope of their performance, and while fuel economy is just as important, this has to be delivered at altogether higher speeds and loads with total disregard for exhaust gas emissions. So while the 2.4 litre V8s were effectively mandated to run as port-injected devices (a 50 bar limit on fuel injection pressure), the 2014, V6 power units appear to be able to use either port or direct injection depending on the precise fuelling characteristics needed at the time. The only provisos as written in the 2014 Formula One technical regulations are a limit on the injector supply fuel pressure of 500 bar, only one direct injector per cylinder, and that according to rule 8.5.2 (page 24 of 77): “Over 80% of the maximum permitted fuel flow rate, at least 75% of the fuel flow must be injected directly into the cylinders.” With no emissions to worry about, and cycle-to-cycle variations under cold start, idle and warm-up, the challenge for the race engine designer is exacting but still very much different from that for a roadcar engine.
So while there may be many other areas where the red-hot technology of powertrain design may be helpful to the roadcar designer, in the case of the 2014 V6 base engine – at least in the beginning – the initial direct-injection knowledge may come from the road engine guys.
Fig. 1 - How Formula One engines used to be – the BRM 16-cylinder ‘H’ configuration engine
Written by John Coxon