Aston Martin wants hyper-car to be faster than F1 cars

[humble sabot]

So, thinking about the rear suspension. I was wondering, would it make sense to fit a long control arm setup? Or is it conceivable that they might be going a similar way to Ron Mathis, who's also a race car designer working on a road car platform:

I do wonder if it would still be so light if it was engineered to deal with 4g of cornering, but it apparently works pretty well on the 900-1000lb Edison 2


Pretty sure the GTR LM Nismo setup isn't germane since it's unpowered and the geometry doesn't fit.

[joseff]

http://www.thedrive.com/supercars/4400/ ... 1-hypercar

“This will be an all-new V-12, much smaller than the DB11 motor,” Reichman told me. “It takes all of the knowledge of Formula One that Adrian has gained, not only at his current employer, but at Williams and McLaren as well.” Reichmn said it will rev to an astounding 11,000 rpm. “We may be saying farewell to this kind of powertrain, so we plan to produce the best of the species.”

[ChrisDanger]

So, thinking about the rear suspension. I was wondering, would it make sense to fit a long control arm setup? Or is it conceivable that they might be going a similar way to Ron Mathis, who's also a race car designer working on a road car platform:
http://static3.consumerreportscdn.org/e ... ension.jpg
I do wonder if it would still be so light if it was engineered to deal with 4g of cornering, but it apparently works pretty well on the 900-1000lb Edison 2


Pretty sure the GTR LM Nismo setup isn't germane since it's unpowered and the geometry doesn't fit.
http://www.racecar-engineering.com/wp-c ... upnis6.jpg

Isn't that bad for unsprung weight (1st photo) and moment of inertia (both photos)? I thought that was why F1 had as much as possible near the centreline of the car.

[humble sabot]

Both good questions. The shock absorber being right next to the wheel does suggest a very decentralized mass, but at the same time even fancy F1 control arms are not super light in absolute terms. The Edison 2 design (1st) works out to being significantly lighter than a typical roadcar suspension in terms of unsprung weight, but being designed around less than 100hp and even less car weight than the amrb001 the advantage may disappear once it needs to deal with the higher loadings. The second one doesn't impact moment of inertia nearly as much as the first but the suspension geometry is a little compromised with the really short arms.

[godlameroso]

That´s true. But batteries have the advantage (compared to a ICE) they can be splitted in several packages and placed at different locations to optimize CG. Maybe not enough with a design this aggressive tough

A Model S drags north of half a ton in batteries alone. Another 170kg for motor and inverter. The ICE would probably run below half that weight on a full tank.

The Model S with old battery packs sure. The new one is just over 1,300lbs(~600kg). The motor and inverter are actually very compact and light for the power level. An LS3 all aluminum crate engine weighs ~190kg, then add oil, coolant, transmission, drive shafts, differential, prop shaft, and you're looking at roughly 285kg powertrain. The big issue is energy density, gasoline is much better than batteries are right now. Cutting 1/3 off the weight of the battery pack for the same power makes electric cars seem very attractive.

With the efficiency of an ICE being roughly 40% most sporty cars have ~85-140kWh worth of gas in the tank. My street car with an engine rated for 170kW will burn through a 12 gallon tank in about 30 minutes going flat out which works out to about 85kWh's. The weight of the powertrain is ~690lbs(313kg) with a full tank of gas and full fluids. So my car's powertrain is half the weight of the Tesla S. Again if they could cut the weight of the battery pack by 1/3rd I'd seriously consider a pure electric car.

[ME4ME]

With the efficiency of an ICE being roughly 40% most sporty cars have ~85-140kWh worth of gas in the tank.

40%, is that accurate? Sounds on the high side to me, or are we talking hybrids?

Anyway I agree with your assessment, although I think for a hypercar, people would want the range and general excitement of a combustion engine. Range is managable in case of roadcars, such as the Tesla Model S, but not for a car that will been driven on track. Nobody wants to suspent a track day in order to recharge the cars' batteries.

[godlameroso]

I'm being purposefully conservative, as I find it's easier to make a point when using conservative estimates.

Underpromising and overdelivering is a viable strategy.

[graham.reeds]

I'm being purposefully conservative, as I find it's easier to make a point when using conservative estimates.

Underpromising and overdelivering is a viable strategy.

A normally aspirated engine of a roadcar is roughly 29% efficient and has been for years. The first season of the new F1 formula they managed to get 40% efficiency, prior to the switch they had stagnated at 29% also. They are now (according to Mercedes blurb) about 45% efficient.

The next chunk of power will probably be recuperating front brakes.

[Tim.Wright]

So, thinking about the rear suspension. I was wondering, would it make sense to fit a long control arm setup? Or is it conceivable that they might be going a similar way to Ron Mathis, who's also a race car designer working on a road car platform:
http://static3.consumerreportscdn.org/e ... ension.jpg
I do wonder if it would still be so light if it was engineered to deal with 4g of cornering, but it apparently works pretty well on the 900-1000lb Edison 2

I don't get the point of that axle. From a bit of reading up on their blog it claims to "significantly reduces mass, complexity, parts count" and "We believe we can replace the twist beam suspension, even in existing cars". However, looking at this suspension it looks heavier, wayyyyy more expensive, has more parts and obviously a restricted wheel travel compared to a twist beam.

Anyway, a suspension which replicates a twist beam has no place on a proper sports car. Far to many compromises in weight and kinematics.

[Andres125sx]

I'm being purposefully conservative, as I find it's easier to make a point when using conservative estimates.

Underpromising and overdelivering is a viable strategy.

A normally aspirated engine of a roadcar is roughly 29% efficient and has been for years. The first season of the new F1 formula they managed to get 40% efficiency, prior to the switch they had stagnated at 29% also. They are now (according to Mercedes blurb) about 45% efficient.

50% efficiency improvement, and people complain about the sound... I know many people is a lot more sentimental than myself, but since I´m a very pragmatic person I simply can´t understand people complaining about sound when the engine is producing 50% more power with same fuel, in just 2-3 seasons. When I see people complaining I can´t stop myself thinking... "do you consider more important sound and tone than power and efficiency". That´s the way I see it.


High revving engines have expiring date, like ICEs itself, but this one is much much closer. If you really enjoy that sound so much, you should be purchasing a car with such an engine to enjoy it while they last, seriously

[Tim.Wright]

I think its to do with the fact that no-one gives a crap about the fuel use and the thermal efficiency but this is a completely different argument.

[Andres125sx]

Agree... for the average F1 fan. But I was talking about F1T members, and here in F1Technical I assumed people had an interest on engineering, so should be interested on a new technology/rulebook wich caused such a great step forward in efficiency. 50% improvement in just 2-3 seasons looks unreal to me

Probably my mistake

[Tim.Wright]

As an engineer/technical enthusiast I see F1 powertrains as an overcomplicated-suboptimal solution forced upon the teams by skyrocketing minimum weight requirements - developed at a completely unsustainable cost for purely commercial reasons which all in all has had a negligible effect on the actual racing.

That's not engineering - it's politics and marketing.

Something I like about this AM-RB tie up is they aren't so attached to this political nonsense. And in effect you can't be if your final target is performance.

[rjsa]

As an engineer/technical enthusiast I see F1 powertrains as an overcomplicated-suboptimal solution forced upon the teams by skyrocketing minimum weight requirements - developed at a completely unsustainable cost for purely commercial reasons which all in all has had a negligible effect on the actual racing.

That's not engineering - it's politics and marketing.

Something I like about this AM-RB tie up is they aren't so attached to this political nonsense. And in effect you can't be if your final target is performance.

Haven't seen a better summary of the current engine formula. =D>

[bill shoe]

I see F1 powertrains as an overcomplicated-suboptimal solution forced upon the teams by skyrocketing minimum weight requirements...

=D> =D> =D>
One quibble with your superb rant. I had the impression the ever-fatter cars are caused by the heavy hybrid powertrains, not the other way around.

Here's a thread on the Tyrrell 003, a beautiful F1 car at 1100 lbs: http://www.f1technical.net/forum/viewto ... 15#p638515