ringo wrote:wuzak wrote:As regards the 3.5 bar (abs) manifold pressure Renault have put forward, didn't the Honda RA168E run at 3.5 bar (abs) - 2.5 bar boost - for the 1988 season achieving 680hp @ 12,000rpm?
Well if you check the fuel mass flow rate at that power level you will see why these engine's today will be different.
Compare whatever that number is to the 100kg/hr.
Source:
http://www.grandprixengines.co.uk/Egs_6 ... _Honda.pdf
Expensive is quite correct that the waste gate pressure was 2.5 bar. The engine had an R rating of 611 bhp or 455.6 kW. The consumption was 284 g/kW.h. That results to a mass flow of 35.94 g/s of the Toluene fuel, which is not comparable with racing petrol.
The source also says that the brake thermal efficiency was 30.6%. With this value we get a fuel energy flow of 1489 kW. If we divide this by 46 kJ/kg for petrol we arrive at a substitute petrol fuel flow of 32.4 g/s. That is just 16.6% more than the 2014 F1 fuel mass flow rate. Quite an impressive achievement for 1988. Part of that success was the fuel that allowed a compression ratio of 9.4. The other important factor was the design of the turbo with ceramic materials for the turbine rotor and the bearings allowing 1000°C and giving very low inertia compared to steel. Hence the driveability was excellent for a late eighties turbo engine.
The Honda engine had a red line of 13.000 rpm and max power at 12.500. So it was considerably higher revving than we expect the 2014 F1 engines to run. I do agree with X that Renault do not need 3.5 bar to run at peak power. But one can speculate that they will perhaps have a safety car setting with ultra high boost and very low rpms. It just doesn't make any sense to me. Unless you deliberately risk to under fuel the car any fuel saving in a safety car period gives you no benefits in 2014. You cannot burn the excess fuel that you save. So this 3.5 bar is a red herring to me.
