Quarter mile

It's only a matter of time before someone cracks the 918 ecu and extracts more power. I am pretty sure there is an extra 100 hp on the table with the gas/electric motors. I know its a super fast car to being with but for some it's almost impossible to leave it stock knowing that there is more power waiting to be unleashing with just a software update. Will it happen? And how much extra power is available?

Exciting stuff!

Whoopsy

The engine itself is already pretty highly stressed, not much left to be squeezed out. And Porsche only guarantees them to make a minimum of 608HP, they could already be making more than that but only Porsche itself have the exact output on file for each engine.

The e-motors 'could' in theory be squeezed to extra more, at a cost of reliability. Don't think anyone is interested in doing it.

Quarter mile

Knowing porsche there is room to make more power in both gas and electric motors. I agree that there isn't much power to be gained in the gas motor but the electric ones surely have an extra 15-20%. I wouldn't want to be the first one but I am game for mods if it's proven on someone else's car. I know it's selfish but it is what it is, at least I am honest 😊

Scuderia980

Even though the exhaust setup from factory is pretty high end, there is still headroom there with more efficient cats and silencers. Stock setup still has to meet emissions and noise constraints. Breathing is already near optimal from factory, so for more HP, max engine speed would need to be increased and mapping adjusted accordingly. The stock motor with current internals should be good for 10k rpm, which is also the same range Ferrari engineers have indicated that their V-8's are at, but the desired balance of power vs reliability is set at 9k rpm. Cost no object and long service life not a priority, full 'race' internals--crank, rods, pistons, etc, using conventional spring cam set up, 12-13k rpm is attainable before any 'serious' valve float concerns would even set in, with hp/rpm curve based on 3.4 litre RS Spyder engine (11k rpm limit for power/reliability as raced), you'd be looking in the region of 750hp from the petrol V-8 alone. Also, for reliability desired, the e-motors are operating below the threshold of maximum kW available from the battery systems. Even for such an incredible machine, there are still margins to be exploited if you are willing to live with unavoidable trade-offs.

Whoopsy

Squeezing another 23+% of power out of a highly stressed NA engine? 23% is not even easy to do with a turbo-ed engine.

At 750HP, the engine will be putting out over 163HP/L, and at 132HP/L, it is already the 2nd highest output per litre engine behind the Speciale engine.

The exhaust has no sound constraint, it is a hybrid so the majority of the testing is done on battery. At full song, Laguna Seca will kick the 918 out because it is too loud.

Here is a shot of the pair of cats on the 918, for comparison, that 2 white pieces of bodywork is the panels between the roll hoops, behind the cabin, on either side of the rear window.

The other shot is the exhaust headers coming out of the engine, normally hidden under the cats and mufflers.

CW-VIESOCK

She has enough reliable go already. The little that can be found with what's there now, is negligible, if not silly, in any world. Porsche would be the only entity that could add anything significant to the platform, without a lot of grief.

WSH

Why ????

Whoopsy

Perhaps some people thinks it's better to put some touch up on the Mona Lisa.

Quarter mile

Why not?

Extra 100 horsepower would make the car that much more fun. The awd/chassis can handle it without safety issues (imo). Porsche is always conservative and I sure there an extra 80-100 hp in the electric motors alone. We only need a test car to experiment and it won't be mine 😊.

Apolo1

The last thing a 918 needs is more power imv

Whoopsy

An extra 30+% out of the 2 e-motors? You on drugs?

There might be another 10% in the e-motors, but as a owner I don't even think I want it. It is fine as it is right now.

E-Man

Have you DRIVEN a 918? The car pulls so hard it's difficult to wrap your head around it. Plus who would be willing to void their warranty on a $1M plus car? Makes no sense.

Scuderia980

incredible engineering work of art. as per extracting more power, i was just spitballing based on what i remember from Racecar Engineering some years ago. As with any NA engine that is pretty much maxed per atmospheric efficiency, increasing engine speed is the only way to increase hp. Based on 3.4L RS Spyder architecture...and given this 918 specific lump's displacement and breathing, it's a good est. of approx. 50-60hp per every extra 1k rpm. However, with each 1k rpm increase, the internal stresses grow exponentially, thus necessitating completely bespoke and new class of internals. With that comes a new set of compromises in reliability/service life and driveability (this aspect has improved a lot over the last decade however...with advances in coatings tech and metallurgy), Owners of such a car (such as yourself) may or may not be inclined to what amounts to turning an already costly machine into an even more costly RSR type. My point was merely that depending on how far one is willing to go, there is more to be had. I know that's not what the OP was getting at, but I'm merely suggesting extreme. Years ago, a friend of mine had this crazy idea of really owning a street legal race car...set out to build a 10k plus rpm M3 GTR. When it was all said and done, that engine was really turned into a rabid monster. It was an absolute rush hammering that straight six to 10k rpm. To this day, I've yet to experience that kind of 'zero inertia' response and high rpm rush in a street car, because it essentially was turned into a race motor. He thought he could live with the 'short' rebuild cycle that was inevitable...but he was wrong. it just turned out to be A LOT more costly than he thought it would be...both money and time wise. The full race internal engine components alone ran more that the orig cost of that second hand M3 he used. He was nuts. But I had a blast every time that I got to drive it.

Scuderia980

doesn't Porsche official numbers have the emotors (combined) operating around 50hp below the absolute max of the battery system's output? The car is so fast as is, the extra hp that us non-owners and bench racers want in theory is merely useful only for magazine racing at speeds over 150mph.

btw, my 'perfect' 918 would sound like this. This 3.4l unit IMO is the best sounding V8 engine ever (sounds like a hybrid of F1 V10 and V12). It actually sounds more F1 than a actual F1 V8 engine. the exhaust was specifically routed to achieve this desired sound.

Whoopsy

Hmm, no.

The architecture of the 918 engine was derived from the RS Spyder's V8, but outside of being a flat plane 90 degree V8, they have nothing in common.

Porsche cast a brand new block to enlarge the displacement to 4.6l, removed all auxiliary power take off, and swapped the intake and exhaust side. Basically a brand new engine.

Because of the bigger displacement, it can't possibly rev as high as the RS Spyder V8, so it's not easy to just add another 1000 rpm, the max speed is dictates by the peak piston speed and the total mass of the internal components. Making it go to 9150rpm right now is already a great achievement. There is no free lunch in tuning an engine, if they do manage to squeeze another 1000 rpm out of it, yes the HP will increase, but there will be a corresponding drop in low-mid range torque, something that's not desirable as the low-mid range 'punch' is what the 918 is famous for. The engine, as it stands right now, doesn't really have a lot of head room left, neither on the intake nor the exhaust side. It already breath through 2 giant K&N style air filters with some form of ram air effect from the side pods, and the exhaust is already coming out through equal length tube headers into a pair of giant cats, some 10 inches in diameter.

For the e-motors, Porsche while Porsche has rated them at a specific output, I believed those are sustained, not instantaneous. The battery pack will supply a sustained amount of current to the e-motors for their rated output, but has a higher peak current output and that could be counted as 'bonus' power, can't be sustained for long but momentarily will exceed the rated power.