Assetto Corsa Competizione ACC Blog: Car Guides (1 Viewer)

Noztra

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Bentley Continental GT3 - 2nd Gen
After the initial success of the 1st generation Bentley, during 2017 it was clear that the opponents had move to much more aggressive designs, Not even a favourable BoP to the engine power could help the big Bentley against the Blancpain GT series dominators.

Enter the 2nd generation, based on the brand new road model. Completely redesigned to every single part, focusing to maintain the strong points of the old car while improving on everything else, especially some of the most evident shortcomings.

The new car has a transaxle configuration of engine and gearbox. This means that the gearbox has moved back to the rear axle leaving room for the front mounted engine to be installed more rearwards and lower. This lowers the CoG and moves the weight bias backwards, closer to a 50:50 distribution, greatly benefiting traction and handling. It also permits for all the front radiators to move even more backwards, massively improving the aerodynamic design of the front end. Speaking of front end, it now has a much shorter overhang permitting the car to ride lower without risking of breaking the front splitter over kerbs which was one of the big shortcomings of the original car. Even though the car has a shorter front splitter, it manages to achieve the same high levels of downforce while also controlling the flow to the rest of the body of the car.

The rear placed gearbox is not without compromises. The size and depth of rear diffuser is a tiny bit smaller than the old model, but perfect design and development guarantees similar or better downforce levels. The big difference and main focus of the aerodynamic design was to minimise drag. We all know that the Bentley is a massive car with a big frontal area. Many hours in aero testing have been used to make the car as aerodynamic efficient as possible. Incredibly enough, not only they achieve great improvement but they even improved the looks, which was actually a requirement of the manufacturer as they wanted to maintain the elegant looks for their racing clients. Indeed the car is a stunner!

The 2nd generation Bentley also maintains the same twin turbo engine. A well tested engine, reliable, efficient and powerful in all the power band. It now sports even better electronic control and much improved Traction Control, one of the big issues of the old model. It also keeps the costs controlled as there was no need on developing from scratch a brand new engine.

Being a Bentley it remains a very big car, the wheelbase is almost 3 meters long! The improved weight balance, the lower CoG and the downforce, will definitely let you feel the grip in turn in, mid corner lateral grip and traction out of the corners, but the agility is not the best there is. Still, in GT racing, the gained stability from such a long wheelbase is always an advantage, making the car easy to push and exploit its full potential, especially on long fast sweeps.

The chassis is brand new, with improved stiffness while remaining light. The improved suspension geometry helps to get the most out of the big engine. It pays to setup the car in a way to take advantage of its high levels of grip and stability. You can even get alone with more neutral or even oversteery setups and control the car with the steering wheel and accelerator, out of the corners. Try to take round lines with high mid corner speed. You can force the turn in with a bit of trail braking which in the case of the Bentley will slowly over rotate the car. Don’t exaggerate of course, you still have slicks and high downforce to keep under control. The length of the car and the higher inertia will help you to control better a bit of sliding. Point the car to the exit and unleash the generous V8. As with the first Bentley, the new model also has an excellent behaviour over kerbs. Obviously the car isn’t agile and sometimes you need to be aware where the rear end will be after the turn in (sounds like a truck advice), but you can still jump over the kerbs without the car getting too much out of shape

Same powerful engine as the older model, much improved aerodynamics, brakes, chassis, electronics and suspension, one would think that the Bentley was about to dominate the new season. Balance of Performance has a different idea…
In the testing it got evident how the car was improved all around while the big engine could finally push the car in much higher speeds because of the lower aero drag. As you can imagine, the BoP acts precisely to lower the engine output and bring the acceleration and top speed of the car, back to the levels of the rest of the field. It is actually the first “big” frontal area car that has much less than 550bhp (which usually all the big cars are allowed).

Combining the unexpected BoP and the fact that the car was brand new so the team had to explore its potential, it’s not surprising the during 2018 the car performed well but not exceptionally. An updated BoP update at Barcelona, with even less turbo boost for the final race, hints that the team was finding much pace with the car, but the organisation wanted to limit them for the last race and possibly for the future… 2019 is underway and the car already performs very well.

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Ferrari 488 GT3
When Ferrari decides to participate in a series, it does so without compromises. When a couple of years ago Ferrari decided to evolve and homologate the 488 GT3, everybody else was adapting road cars to the regulations of GT3 and different versions for the more extreme GT2/GTE series. Not Ferrari.

The 488 GT3 was designed from the start to be a race car able to compete in the highly demanding GT2/GTE series and with small changes to fit the rules, also in the GT3 series. The result is a highly sophisticated full blown race car. Chassis, suspension, engine and most importantly aerodynamics, everything has been designed by the highly experienced engineers of the “gestione sportiva”, the engineering department of research and development of the “Scuderia” responsible for all the racing cars and of course Formula 1 cars. All this translates to an extremely capable car in every single aspect. When the car first appeared in the tests for the Balance of Performance classification, it was instantly clear that Ferrari had build something extremely capable. Even by sandbagging and asking the drivers to keep it slow, it was evident by the tests that the car could destroy the competition. The most important aspect of the car is its aerodynamics. While the car produces a bit too much aerodynamic drag, it has also clever flow solutions to overcome this at higher speeds. The downforce is probably the best in class and the chassis and suspension offer neutral handling and very good tyre wear behaviour. The mid turn speeds are almost always the highest and the car responds even in the slightest chassis and aerodynamic setup changes.
The engine in the road car, is a twin turbo V8 that has won for four consecutive years the “engine of the year” award. It delivers over 700bhp reliably in the road car with all the emission and noise restrictions. It’s easy to imagine what it can do in race trim, properly tuned while at the same time achieving again top of the class fuel consumption. As this wasn’t enough, it’s power delivery is controlled by a first in class, traction control system, that separately control the amount of slip allowed and the amount of engine power cut for given slip, all at the disposition of the driver at any time, by two separate dials.

It really sounds like a category slayer, so how come doesn’t dominate the Blancpain GT3 grid? Enter BoP (Balance of Performance). The Blancpain BoP follows specific rules and effectively and successfully manages to balance the performance of the big variety of cars that appear in the series. It is a great equaliser but by definition it has to take some unpopular decisions to achieve the promised balance.
How do you lower the performance of a car that has great chassis and suspension design, top of the class downforce, amazing engine controlled by very advanced electronics? Turns out the most reliable method is to take advantage of the electronics of the engine management system and limit very precisely the amount of turbo boost throughout the whole power band. You can argue that the same applies for all the other cars, but if the electronics are not so advanced you can go only that far with intake restrictors until the engineers find ways to bypass this in some range of the power delivery. With the 488, you can be much more precise on what limitations you ask…

Every race results shows the same identical situation. The Ferrari 488 GT3 stuck behind one of the top cars of the series, practically pushing in the middle of every turn, digging its nose under the diffuser of whatever car at the front during the long straights, but never getting out of the slipstream to overtake. When they do, it’s almost comical to see the car losing speed because of the low power and drag caused by the high downforce. It drives almost like a prototype but then has no power to overtake in the straights. All the 488 drivers know this and really deserve our applause and reward as they fight and duel with other cars in every single race.

To be able to race and overtake, the car need to sacrifice some of the rear wing angle to generate a bit less drag. But the front splitter and diffuser generate a lot of downforce to the front, so in order to balance the car, it often needs to be run in negative rake. That means the front slightly higher than the rear. This will bring the aero balance back to the rear again making the car more stable at high speed turns. As usual for the GT cars the front suspension bump must be carefully controlled with bump stops to stop the car from pitching forward under braking and turn in and maintain stability. A bit of turbo lag might compromise occasionally the traction, but with so many options in the traction control, it’s not a big issue. The dampers are specially made on Ferrari specifics. They might not have the wide range of the Öhlins, but they do their job properly. You will also need to use them in unconventional ways. As described above, the car has a particular low CoG and race suspension geometry made specifically to save tyres life. This is a great advantage in the GTE WEC series where the tyre manufacturer creates specific compounds for every car. Unfortunately in the GT3 series the tyres are identical for everybody with just a single compound for any track, any weather combination. This is a great achievement from a tyre manufacturer and an effective cost control. Unfortunately in a combination of cold weather and slow circuit, while the other cars manage to keep the tyres in temperature, the Ferrari often finds itself not to be able to keep temperature on the tyres. Stiff springs and dampers can help with that, but obviously it badly compromises the handling of the car, which normally should be the advantage of Ferrari.

Speed at the apex is paramount so the drivers need to adjust their driving style accordingly. Late braking, smooth lines, precision and early power application are needed in order to make the car deliver lap times, but the car actually helps the driver to achieve this. It will also take more aggressive driving styles and will remain relatively sincere, but much time is lost this way, as the car doesn’t have the power to recover from sloppy driving. Lowest fuel consumption and lowest tyre wear also helps in endurance races, although Blancpain rules force pitstops every hour and thus almost eliminating such advantages, equalising all cars. Still, using less fuel than others, taking advantage of the less tyre wear as the rules give a limited set of tyres for each weekend, can make the car shine against competitors and aim for the podium in many circuits, making it definitely one of the top cars always capable of winning. Sponsors are also always keen to be on a Ferrari…

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BMW M6 GT3
The brand new BMW M6 GT3 made quite an impression in 2018 Blancpain GT3 series.

Following the dimensions of the street car, there is no denying that the race car is also very big, even bigger than the Bentley, especially in length and wheelbase. This same aspect, together with the impressive twin turbo V8, define the handling characteristics of the BMW.

The dimension of the car, results in a very large area of the underbody aerodynamics. The front splitter is impressive and the length of the rear diffuser is massive. Even the exhausts have lateral exits so that they do not interfere with the diffuser aero flow. Many smaller or bigger details can be found all around the long bodywork, achieving impressive amounts of downforce on par with the top of the class, even though the total drag inevitably stays a bit high given the big frontal area.

Nevertheless, the absolute aero numbers tell half the story. The best feature of all this attention to the aerodynamics is the quite stable aero platform. As we have explained in other posts, the main issue for the drivers of modern cars with high aerodynamics, is the stability of the aero platform in terms of aero balance, from the effects of pitch and roll. Often, the higher the downforce, the more sensitive the car becomes to pitch and roll, forcing the engineers to big setup compromises that make the car worse at low speeds, and forcing the drivers to change their driving style at higher speeds, in order to not upset the car. The later is easier to tell than do, especially for amateur gentleman drivers that participate in the Blancpain series.
The long wheelbase and long under tray of the BMW, deliver a much more stable aerodynamic platform, especially under forward pitch (coasting, braking) that permits softer suspension setups and more natural driving techniques to be exploited. At low speed the car offers exceptional turn in and minimal amounts of understeer at power exits. A hint of understeer is present at the apex of slow turns, which is typical for such a big car with a bit of front weight bias, but it adds confidence to attack the corners at entry and can be easily controlled by the drivers. As the speed raises the big amount of stable downforce, result in a very confidence inspiring car that can be pushed at high speeds and if the driver makes the occasional mistake, it can be relatively easily corrected.
The very very fast right hand bend at the end of the long back straight at Paul Ricard is the perfect example of the car’s stability. Even if you overcook the entry going in way too hot, you can confidently raise your foot or even pinch the brakes and the car will correct it’s trajectory without big drama. Not something you can do with the much more pitch sensitive Huracan for example.
Similar situation at the Misano circuit. The very dangerous braking zone for T13 and T14(Carro) turns, must be approached in a very certain and precise way, by practically all cars. The BMW M6 showcases great stability and honest reactions, giving the driver the opportunity to attack and trust the car, without big setup compromises.
Fantastic car then, is this the best of all worlds? Not so fast.
The very very long body and wheelbase, does indeed provide stability, but predictably enough, makes the car sluggish at narrow turns, chicanes and fast direction changes. The car turns in fast but then needs some time to take a set and keep the line. The perception of the limits of the bodywork is also not so good and this is a disadvantage in close racing situations.
Worse of all, the very long overhangs touch the ground easily and they will do often do so at the very worse moment at very high speeds while trying to ride a kerb in a very fast corner. The resulting loss of tyre grip and aerodynamic stalling can bring catastrophic results. This is where compromises have to be made on the setup, by rising the ride height, using stiffer springs and dampers and so on. Drivers must also adapt and find which kerbs should ride and which ones are better to avoid. In such situation the excellent behaviour of the BMW can quickly betray you and make you spin in no time at all. Beware.
All in all, the car forgives some aggressive driving and a bit less precision, but it really shines when the inputs are smooth, both on the steering wheel and on the accelerator pedal. The smoother you drive it, the more speed it gains. The advanced traction control, is finely tuned for safe driving but lowering it to level 3 or less, will permit even more forward acceleration if you are smooth on your inputs. In a way, it is as if the looks of a grand touring coupe are mirrored one to one on its handling behaviour.

The big V8 placed behind the front wheels, produces massive amounts of torque and power. The favourable Balance of Performance, let the engine output around 650Nm of torque and approximately 550bhp. Most importantly the torque curve of the car seems like the great plains, or siberian plains, or Netherlands, or padania… choose whatever fits your definition of flat and infinite. Unfortunately it’s not what I would call an enthusiastic engine. Even though it pulls incredibly from as low as 3000rpm, the party ends at around 6200rpm. It feels a bit like a very big diesel engine and you need to keep changing gears as fast as possible as it arrives to the top end of the power in no time. Occasionally you won’t even be able to hear your own engine sound while changing at around 6000rpm, while an attacking Audi or Lamborghini are screaming besides you at over 8000rpm. Still, after 2nd gear and with the rear tyres finding traction, there not many cars that can beat you in a drag race down the straights.
There is some turbo lag but it is taken care of with an anti-lag feature which makes the exhaust gurgle and our sound engineer happy. All this generous torque can easily result in power oversteer at any speed and gear, which normally would make the tyres unhappy but the very advanced new generation TC, helps both amateur and professional drivers, position the car properly and at the same time results in a big smile in their faces. Don’t overdo it though because after then smooth and gentle initial drift, the long rear end starts to slide and slide and slide even more, raising the heartbeat and destroying the tyres.
Keep it all together and you’ll be rewarded with a best in class acceleration out of the turns. Yes the Huracan has amazing traction and the initial acceleration is great while the TC intervention is minimal… Yes the Ferrari 488 mid turn speed is incredible. Yes the Mercedes GT3 balance is exemplary… but keep them behind you and watch them become smaller and smaller on your rear view mirror as they can’t even keep the slipstream while you roar towards top speed. Which you will hit fast… and hard. As a matter of fact, the car arrive at a high top speed very fast and then it hits a wall. A wall of air resistance as the drag hits and stops the car. This is when the other smaller cars will start closing up to you towards the brake zone and so the play starts again… Overtaking you though, that’s a whole different story.

No surprise then that the car managed to win the 24Hours of Spa, at a track famous for it’s mid to high speed turns and long uphill straights. Look at the narrow bumpy Brands Hatch race though and you’ll get the opposite side of the coin.
That is what the Blancpain series is all about, isn’t it?

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Audi R8 LMS GT3
The Audi R8 GT3 is undoubtedly one of the dominating cars of the Blancpain GT3 series.
It’s not just that it constantly scores pole positions, fast laps and overall wins in practically every circuit. It gets these results with almost any team and any driver using it. This is the proof that the Audi R8 is a very capable car, always efficient and fast.

You’d been forgotten to think that the Audi R8 is a Lamborghini Huracan GT3 in disguise, or vice versa. After all the cars have the same chassis and the same engine. The wheelbase is also identical. But this is where the similarities end. There are differences in suspension geometry, there are differences in the engine tune and power delivery and there are many differences in the aerodynamic efficiency and performance. It is evident by the base setups of the car, that are quite different from the Huracan counterpart.
The Audi usually likes stiffer rear end, it helps it rotate it and it maintains the rear suspension movement under control. Even the rear antiroll bar is pretty stiff as it keeps under control the, lack of, camber gain when the car rolls. A good amount of negative static camber helps.

Obviously when you drive the car, some traits are similar. The power delivery, the electronics, the sound… all things that are truly very similar to the Lamborghini. But then, the differences start to come up to the surface. At turn in the car wants to oversteer like the Huracan but does gives a bit more confidence while doing it. At mid turn and exit the front end is willing to follow the steering inputs better. This means the engineer is not forced to use extreme setup to rotate the car and the driver doesn’t have to abuse the car to follow the line. All in all, where the Huracan is on the edge, the Audi seems more composed and steady. I won’t say it inspires confidence, because it really doesn’t when pushed to the limits, but you have a better idea of where the limit is, or at least that’s the impression.
Is this a better car than the Huracan? Well no, it’s different. The neutral handling in mid turn will bite hard at you when you try to ride kerbs. You can compromise, you can set the car more stable and it works, but if you really want to go fast then watch out riding the inner kerbs. The car will rotate fast and at the very best case scenario you will lose lot’s of time trying to control it. Otherwise you’ll spin out of the track with your tyres flatspotted and many places lost. It’s best to approach turns with a V line. Brake late and go for an early apex without turning it too much to keep the rear end stable. Once you’ve passed the early apex and the speed is slower, rotate the car fast, away from the kerb and point to a second late apex and a straight exit, taking advantage of the rear weight bias traction. This kind of turn approach keeps the mid engine architecture traits under control. Great agility and grip, nasty behaviour when unsettled.

The engine seems a bit less powerful than the fastest Huracan team, which is strange because it should be the same engine, but the feeling is that it is more docile at power application out of the corners at the expense of a somewhat slower acceleration. We’re talking really minimal differences though.

Audi’s great experience in the LMP1 category has paid dividends in the car’s aerodynamic efficiency. As a matter of fact the rear wing comes straight from the LMP1 car design and it has very well documented aero map so it needs less adjustments to be efficient and helps the teams by avoiding unnecessary complexity. The results are evident as the Audi is always on the top of max speed traps at high speed circuits, without losing much downforce. This is indeed a great advantage in the middle of a race. Not only the car can keep up in terms of handling and overall grip, but it can also get out of the slipstream and still keep accelerating, obtaining a great position before the braking zone. If you feel uncomfortable with the aero balance of the car, you can always add a bit of rear wing, confident that your top speed will still stay competitive with the other cars.

Another advantage of having so many cars on the grid, by so many different teams, is that there is a lot of knowledge regarding the car, its traits and the setups needed to go fast. Information does go around in the Blancpain paddock and when the “Audi armada” decides to attack, the combined knowledge does give a competitive advantage.

So is the Audi the car the car to chose if you want to win? It is a good candidate, and with the help of somewhat surprisingly favourable BoP, it can win on almost every track, but it’s not alone and if other cars push it to choose different racing lines, it might show its ugly face. Be sure that there are other cars out there that can really push it to its limits.

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Noztra

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Lamborghini Huracán GT3
The 2017 champion car, arrives in the 2018 season in an almost identical form. The Huracan GT3, proved in the 2017 season, to be the car to beat in terms of absolute performance. Nevertheless this top level performance was the result of a very professional team with very talented and fast pro drivers that especially on some tracks were able to destroy the competition. The result of this was a very severe Balance of Performance handicap for all the Huracan cars, that heavily penalised the champion team but most importantly all the other teams using the car, further down in the grid and classification.

Objectively the Huracan GT3 is a very capable car, but at the same time it has some very unique and distinct characteristics that often make it difficult to handle for less experienced teams and drivers.
The car is very compact resulting in a very small frontal area and thus very low drag figures. Top speed is almost everywhere amongst the highest achieving cars, often topping the results. The downforce production is also very high, maybe not on par with Ferrari, Audi and Mercedes, but not that far either. The resulting efficiency is top of the class confirming the qualities of the Lamborghini aerodynamic design aided by the famous Dallara engineering. The compactness of the car dimensions, result on a very small under tray area that is quite pitch sensitive. At high speeds the car will become quite unstable under coasting or even worse, braking. As an example the very fast right bend after the long back straight at Paul Ricard has gave me some of the most violent slap tanks in my whole real and simulate driving life. Brake a bit too hard and a bit too late from 280kmh top speed and try to turn in and I can guarantee you, you’re going to change your mind very fast and thank Paul Ricard circuit designers for implementing those very wide runaway areas with blue and red lines that give even higher grip than normal asphalt (at the exchange of massive chunks of tyre tread flying around…). Small amount of ride height change at the front or rear, will move the aero balance quite a bit back and forth. To counteract this, the suspension setup must be adequate to aid the stability under such conditions, with high front stiffness and good damping work in front bump and rear rebound, more similar to a single seater setup, than a more conservative GT racer. The stiff setup will usually make the car jolt and jump around over kerbs and bumps, but surprisingly enough it will stay quite stable if the driver is precise and remains on power.

The mechanical balance of the car is also particular. The road car has an AWD setup that adds weight to the front axis from the axles and differentials. The GT3 car, by rules, has to be RWD and so the elimination of all the AWD mechanical parts, results in a very rear weight bias. As a matter of fact, the Huracan starts with about 60% of its weight at the rear tyres making it practically a very rear heavy car, similar the Porsche 911 that, let me remind you, is rear engined! A car with such weight bias, would need a staggered tyre setup. This means that the rear tyres should be wider than the front, to handle better the different loads. Unfortunately the tyres offered by the rules, have very similar dimensions for both front and rear which means the mechanical grip is a bit unbalanced with more tyre at the front, than what the car needs.
To the uninitiated, this might sound like a non issue. The car seems to understeer constantly, so more tyre to the front, can only fix the things right? Why does it make it worse then? To have balanced handling characteristics you need to have a predictable rear grip, so that you can shift the weight with your driving inputs and you get back predictable feedback and reactions. If you have more rear grip than front, then you can use the power on the exit of the turns to rotate the car and it will do so gradually, because even if you lose some lateral grip, you still have plenty to handle. But if you have more grip at the front, the moment you get power understeer (and you’ll get it because of the weight bias to the rear), then trying to power oversteer will subtract important amounts of grip from the rear and it will make it skittish and nervous. On top of that, add a quite sensitive aerodynamic platform that we described above, that moves the aero balance heavily to the front and to the rear every time the pitch of the cars changes by mere millimetres and you get a more clear view of why the car requires skills and respect from its driver.

Sounds like a difficult car to handle and it is when you try to push it hard on the limit. Setup must be balanced and on the stiff side, especially at the front. Don’t try to overcome the power understeer with a more oversteer setup, because you’ll end up with a nervous turn in that will make the car slower. Embrace a hint of understeer, be more precise in your inputs and driving line and learn to take advantage of the aero platform and mid turn speed. You can brake late, start to turn in, but get off the brakes as soon as possible and let the car coast to the apex or with a very very slight brake input, anything more and it will understeer at turn in too. Learn to do the coasting part properly and you’ll be surprised by how much speed you can carry inside the turn, which will be translated in time gains outside of the turn. This is taking advantage of the aero platform, leaving the car as flat as possible instead of forcing it to turn by braking and pitching. The results might surprise you.

If properly setup and driven, the Huracan GT3 showcases a very fast turn in and high mid turn speeds. Exceptional traction and agility makes it perfect for slow narrow turns and chicanes. There’s always an understeery behaviour on power at the exit of the turns and generally the car doesn’t like to change its line once in the turn. Precise driving and proper racing techniques are required to make the car deliver, but even thought it might not feel “fun” and requires lots of self control, concentration and commitment, it is capable of blazingly fast laptimes that reward all the hard work.

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Bentley Continental GT3 - 1st Gen
The first-gen Bentley Continental GT3 car is... a tricky beast to say the least. The car is heavily based on the street version and this translates in certain aspects of its handling characteristics.

Although the big V8 twin turbo engine is placed behind the front wheels, the car still has more front weight bias. This, together with a higher center of gravity than other GT3 cars, makes the car more prone to roll during turns and results in more weight shifting. On the other hand, the Blancpain Balance of Performance (BoP) permits bigger front tyres for FR cars and those do help the Bentley to have a surprisingly good turn in.
The front weight bias provokes a moderate understeer in mid turn, but it is easily manageable by pressing a bit more on the accelerator and letting the big engine rotate the rear end and point the nose towards the exit of the turn.

Speaking of which, the 4.0-liter V8 twin turbo engine is obviously heavily restricted, but the BOP permits higher torque and power outputs for cars with significant frontal area and thus high drag. As a result, the engine delivers more than 650Nm of torque for a very wide range of revs and around 550bhp of maximum power.
This is both a blessing and a curse as they say. The massive amount of torque is putting under big stress the fat rear tyres and more often than not, manages to break traction, aided by the fact that the rear end is lighter than the front. The traction control does help a lot but it is very intrusive doing so. Lower TC levels are needed in order to get all the potential performance of the car, but it seems that its response is not linear and at lower levels the torque and power can be delivered very violently and can make the rear wheels spin a lot before intervening. When this happens, the very big body of the car can become quite a handful to control, showcasing a completely different aspect of its handling characteristics and becoming much more difficult to control.

The aerodynamics, as usual, play a big role in the performance of any GT3 car. The Bentley is big, there is no denying about it. The frontal area creates a lot of drag and this is only partly counterbalanced by the powerful engine. Certainly the car accelerates very fast out of the slow to medium speed turns, but at higher speeds it simply hits a wall. Not much that can be done about it.
The very long front splitter is another aspect that you must consider. Although it produces quite a big amount of downforce, it is very prone to touch the ground and especially the kerbs. The splitter is very strong to be able to sustain the downforce but on the other hand it means that when you hit a kerb with it, if it not breaks, it can make the front end jump and instantly lose all grip from the front end. Take into consideration this fact when setting the front ride height and the rake of the car. A compromise is needed to keep the splitter off the ground while still producing enough downforce. The very same compromise might introduce a moderate understeer at high speed turns, when the power isn’t enough to make the rear end aid the turning.

Finally, the high drag figures, certainly do not help much with fuel consumption, and the tyres might suffer from all the torque available. Nevertheless, with the proper TC and ABS levels, the car can easily achieve impressive laptimes, but in order to find out the extra hidden performance you need to lean less on the electronic systems and more on your driving skills.
 

Noztra

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Porsche 911 GT3 R
The Porsche 911 has always been a top competitor through the years. The unorthodox architecture with the engine hanging at the rear giving heavy rear weight distribution combined with the short wheelbase, has always been judged as extremely unstable for street use. Yet, in the hands of an experienced professional driver, the extremely fast turn in, the agility in changing direction and the best in class traction, always delivered top performance. Sure everybody would complain of instability at turn in and terminal power on understeer at corner exit. Still professional drivers knew how to deal with such characteristics and adjust their driving style to make good use of the advantages. In a class where the cars were heavy and grip was generally lacking, being able to put the power down and change direction quickly was always an important advantage.
The choice of the word “was” is not casual though. Modern GT racing have brought to the grid cars with big aerodynamic improvements, electronic systems for traction control and ABS are adjusting traction and grip circles and modern tyres provide more grip. Speaking of which, because GT3 racing is “client racing”, in order to keep costs low, the tyres are identical for all cars with tiny dimension changes.
The end result is that the Porsche ended up without being able to make a difference with its architectural advantages, while it become even more unbalanced from the tyre dimension availability that often keeps the front tyres out of the operation range.

Aerodynamic advancements are also limited by the architecture. Much of the aerodynamic downforce gains are made from a big rear diffuser that has to be wide and deep enough. Unfortunately for the Porsche, that’s exactly where the engine sits, so the actual diffuser is very shallow and short. That means the engineers have to work a lot on the front splitter and the rear wing. They manage to create substantial downforce, but it is still not enough. It also generates a lot of drag as it needs the rear wing to work in high angles and most importantly, the resulting aero platform has a very narrow window of operation and a very non linear downforce production that creates unpredictable results. In the paddock, you can often hear the drivers complain that the car works strangely whatever the try to do and the engineers complain that they can make the car “work” in a given circuit or condition. As if things couldn’t get worse, most of the cars have their fuel tank near to their Center of Gravity, so that the fuel load only affects the weight of the car but not the overall balance and handling. Not the Porsche; 120 litres of fuel hanging under the front bonnet. Which means that even if you manage to make the car work with a good setup, the whole balance is going to change when the fuel load will change. The car needs quite different setups for race and qualifying sessions. Often teams will add more fuel during qualifying, to help the drivers with a more predictable handling. During the race, the car will change handling characteristics and the drivers must be ready for it. It’s not uncommon to see the car being competitive during one part of a stint, and then get slower for the rest of the same stint as the fuel load changes, or vice versa, depending on the setup compromise the team opted for.

Another limiting factor is the engine. This amazing powertrain screams up to 9000 rpm and it is one of the most praised engines in the road car. So how this can be a problem?
Even though the BoP is not very restrictive, it still has to limit the power to around 500bhp, similar value to the other small frontal area cars. Incidentally this is the same outcome of the street engine. Surely race engines could go higher, but when you start analysing the engine capacity, you realise that there’s not much margin available. The flat 6 engine is normally aspirated and has “only” 4 litres capacity. The smallest engine of the grid is the one of the Honda NSX, 3.5lt but twin turbo. All the other normal aspirated engines vary from 5.2lt V10 of the Lamborghini and Audi, up to the massive 6.0lt V12 of the Aston Martin and the gargantuan 6.2lt V8 Mercedes. Which means that those cars can generate similar amount of power but also massive torque from very low revs. The Porsche engine has to climb up to 9000rpm to achieve the same power and obviously the power band is more peaky. Surely the gearbox ratios can cover the problem, but then again the GT3 series demands a single gearbox ratios homologation that then is used on all the circuits. Some serious compromises must be taken.

Seems like the Porsche has serious disadvantages and predictably the performance of the car was not adeguate of the name in 2018, with the occasional spark under wet conditions where the traction can make a difference and the top speed is not so important. Porsche focused its efforts on the WEC GTE 991 RSR car which was highly modified with the engine rotated by 180° and practically transformed in a mid engined architecture. The car performed much better and surely the engineers learned a lot from that experience. The 2019 Porsche GT3 R car already won the Monza race and is looking good for the rest of the season. So if you want to win with the Porsche, you need to be a bit patient until we release the 2019 version of the car.

Still, all said and done, when you get to drive the Porsche, the shortest wheelbase of the grid, the scream of the flat 6 at over 9000rpm, the amazing turn in, while the rear starts to rotate, the fast and constant workout needed with the steering wheel to keep the car from over-rotating and the sublime lightness of the front end when you put all the power down and the front raises up, makes you forget the shortcomings in performance. The car keeps you alive and alerted at any moment. Brings back memories of vintage racing cars when the driver could make all the difference. When finally you manage to drive it properly the level of self reward reaches new heights.
Forget about top speed, you know you’ll be the slowest anyway. Add rear wing to get downforce, stiffen the rear end to make it rotate, play with the brake bias that can be set way to the rear and start working that steering wheel. The Porsche won’t forgive lazy drivers, it won’t make it easy for you. It demands your total dedication, yes even if you have to race it for 24 hours and doesn’t care if you’re tired. Show the respect it asks for, and you’ll get a different kind of reward that only special cars can give; and if it rains… you might even have a chance for something special.

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