Renault engine fuel advantage

[CHT]

According to Renault, Renault powered cars can run with 15 to 18L less fuel.
How much advantage is that per lap?

http://www.planet-f1.com/driver/18227/7 ... -less-gas-

[ESPImperium]

Thankfully i went back to 2009 and re did my data charts over the winter break, they are running at least one lap less in fuel in comparison to the Mercedes and three laps less to the Ferrari.

If you take an average lap arround any track as 2.51kg, its probably closer to 8Kg to 10Kg at any race.

He states its in Litres [Petrol weight 1Litre = 0.711kg (at 60 deg F)] so it would be arround 10.6kg less in fuel thay would have. 10Kg is wourth rough 4 tenths a lap as a general rule of thumb, so they save roughly that in lap time.

In 2009 the fuel to the average first stop values were as follows:
Mercedes FO108W 60.6
Ferrari 056 65.9
BMW P86/9 64.1
Renault RS27-2009 58.2
Toyota RVX-09 64.2
(All values in Kg and were when refueling was permitted)

[NonNewtonic]

From these stats it seems like Mercedes is te best choice in terms of fuel efficiency and HP. Although Renault is the most fuel economic engine put they are about 5 to 6 HP short compared to Mercedes

[CHT]

From these stats it seems like Mercedes is te best choice in terms of fuel efficiency and HP. Although Renault is the most fuel economic engine put they are about 5 to 6 HP short compared to Mercedes

what about the impact of the extra fuel load on tire wear?

[JohnsonsEvilTwin]

In 2009 the fuel to the average first stop values were as follows:
Mercedes FO108W 60.6
Ferrari 056 65.9
BMW P86/9 64.1
Renault RS27-2009 58.2
Toyota RVX-09 64.2
(All values in Kg and were when refueling was permitted)

Where was this sourced?
And, If I may, what is the "fuel to the first stop" actually mean?
Is it influenced by strategy? ie short first stints, compared to longer ones?

[Just_a_fan]

There are three advantages that come to mind:
1. For a given number of laps the team can use less fuel so they carry less weight at the start. This gives a lap time advantage on every lap.
2. For a given number of laps they can use a smaller tank. This gives packaging advantages.
3. For a given number of laps they can either run more laps at high power and use the same total fuel as the others or they can run the same amount of high power laps but start with less fuel and make 1. and 2. work for them.

[JohnsonsEvilTwin]

@just a fan

Suppose the Renault unit is slightly(ever so slightly) down on power, but more frugal.

What of the less spoken tangent... Packaging?
Look at caterham and Williams along with red bull and lotus, and see how that engine sits so tidily.
It gives aerodynamic benefits by simply being easier to package.
Mercedes may have had the top engine for a few years but 2011 saw Renaults v8 evolve onto a par with the merc all factors considered IMO

[raymondu999]

In 2009 the fuel to the average first stop values were as follows:
Mercedes FO108W 60.6
Ferrari 056 65.9
BMW P86/9 64.1
Renault RS27-2009 58.2
Toyota RVX-09 64.2
(All values in Kg and were when refueling was permitted)

Where was this sourced?
And, If I may, what is the "fuel to the first stop" actually mean?
Is it influenced by strategy? ie short first stints, compared to longer ones?

I think (though I don't know) that this was calculated based on post-qualifying fuel weights. I think (possibly) ESPI went and took all the Renault engine runners; and compared the lap on which they did their first stop; versus the post-qualifying fuel weight - 605 (the then-minimumweight of the cars)

[the EDGE]

perhaps one of the brighter users could provide a graph comparing power to weight ratios of the 2 engines and how that changes as the fuel load decreases

then we could see who has the advantage and when

I think the renault unit would be better at the start but that advantage would swap at about half distance

[raymondu999]

power to weight? I take it you mean weight in terms of fuel + engine? All the engines weigh 95kg

[Just_a_fan]

I'm still not convinced that the Renault is that far off the Merc and Ferrari units in terms of power. Maybe a handful of bhp, if that. And what about driveability? It might be that its power is delivered in a slightly more benign manner which would offset the supposed power disadvantage by making more power available more of the time, in effect.

One of the reasons that Newey argued for the use of the Renault is that it has, apparently, got a better heat rejection figure. This would also allow smaller rads.

So the Renault may give better packaging in a number of ways. It's entirely possible that Newey could not have built the RB7 if he'd had to to use the Merc or Ferrari units...

[the EDGE]

power to weight? I take it you mean weight in terms of fuel + engine? All the engines weigh 95kg

Good point, yes, car + driver + fuel

assuming the merc cars start about 12kg heavier and have an extra 15HP, obviously the fuel will decrease whilst the HP should remain constant

[Pup]

I think we saw the result of this all last year. The first lap pace of the Red Bull was staggering - even after taking into account what we'd expect from their qualifying advantage. Given a clean run, they'd pull over a second on the field every time.

[raymondu999]

power to weight? I take it you mean weight in terms of fuel + engine? All the engines weigh 95kg

Good point, yes, car + driver + fuel

assuming the merc cars start about 12kg heavier and have an extra 15HP, obviously the fuel will decrease whilst the HP should remain constant

Yep; the weight difference would decrease linearly and ideally, in an ideal world; they'd all finish the races at 640kg.

[the EDGE]

power to weight? I take it you mean weight in terms of fuel + engine? All the engines weigh 95kg

Good point, yes, car + driver + fuel

assuming the merc cars start about 12kg heavier and have an extra 15HP, obviously the fuel will decrease whilst the HP should remain constant

Yep; the weight difference would decrease linearly and ideally, in an ideal world; they'd all finish the races at 640kg.

okay I crunched some numbers...

assuming car + driver = 640kg
fuel weighs .711kg/litre
Mercedes uses 250 litres of fuel for the race
Mercedes uses 18 litres extra of fuel per race
Mercedes produces 765BHP
Mercedes produces 15BHP more than Renault
the race is 60 laps long

and produced a great graph on EXCEL but unfortunately I'm too thick to be able to publish it on here (any advice welcome)

however what it shows is at the start of the race REDBULL have a tiny advantage
0.9595 as oppose 0.9567 (BHP/KG)

by lap 11 however the advantage has switched to Merc
0.9896 as oppose 0.9894 (BHP/KG)

and by the end of the race Mercs advantage has grown significantly
1.1903 as oppose 1.1675 (BHP/KG)

Now I understand what Jean François Caubet, Renault's F1 director means when he says 'as far as drivability and fuel economy go, the Renault engine is out in front'

the Renault ways less for the entire race so uses the tyres better and creates less G through YAW movement (maybe I just made that up), however I now also understand why the Merc cars performance gets better as the race goes on