The introduction of the Mulsanne nameplate in 1980 provided Bentley with the opportunity to flex its plushest and most luxury-focused model. In the pursuit of refinement, the original Le Man winning engine was bored and stocked to the famed 6.75Litre V8 displacement for the production model. Later replaced with the Arnage throughout the years, only to return in 2009 with the current model as a 90th-anniversary celebratory model.
Given the new 11-year model run and the L-Series 6.75Litre V8 beginning to be rather difficult to get past stricter emissions regulations and smaller VAG V8 Hybrid powerplants balancing power and fuel economy far better. In commemoration of the momentous 60 years of service, a limited production final edition dubbed the ‘6.75’ will be created. Just 30 of these bespoke models will be conceived by coachbuilders Mulliner. Based on the current Speed Model power remains the same at 375kW and 1100Nm from the Turbo V8. Keen eyes will note the subtle notes that pay homage to the celebration of Bentley engineering history.
A centre console-mounted 6.75 Edition metal placard with the “One of thirty” demarcation the same mantra is hinted throughout the interior and even through to the LED illumination. The choice of four interior colours, contrasted with the silver and high gloss fascias through the front console.
Externally the changes are equally as cunning by Bentley as some fender-mounted rosettes with an L-series specific design and some gloss black accents carried throughout the vehicle are the only telltale sign of the heritage.
Production of the Mulsanne will end in the second half of 2020 and hand the First Class monarchy over to the Flying Spur until its return in 2023
Meet the car which has been banned from the Drag Strip: Dodge Challenger Demon
Power corrupts and absolute power corrupts absolutely. American vehicles in South Africa have always been niche and I personally think that that is a good thing, but with this new Dodge Challenger Hellcat, it’s proving to be somewhat difficult for me to digest. As a spiritual man, the word Demon has bad connotations. You see, no matter how you spin it, in my world, a demon can never be a good thing, even if this demon has a rumored figure of 804 hp that’s 617 kW in South African!
American vehicles have a reputation of being fast in a straight line and lacking in the corners. The new crop of muscle cars seem to negate that but the scales are still prejudice to the straight-line side. This is a muscle car that is rumored to destroy the oh-so American quarter mile in 9.65 seconds at an exit speed of 224 km/h! 0-100 is blitzed in 2.3 seconds and 0-160 km/h in 5.1 seconds. This is courtesy of a stupendous torque figure of 1 043 N.m, and it’s the first road legal vehicle to lift its front axle on take-off. Rears are shod with 315 rubber to make sure that your “11s” can been seen from the international space station.
This ridiculous amount of power comes courtesy of a supercharger that’s bigger than your Golf 7 GTI’s motor at 2.7 liters which is then bolted onto a 6.2 liter V8 motor, resulting in 1.8 Gs on launch. That’s guaranteed to blur your vision while making sure that your eyes are securely lodged at the base of your skull.
All this power and numbers come from the wizardry of computers and you see this in the technical specifications. The de.. Hellcat has specific software to shift weight to the rear to optimize launches, all the while playing with how much torque it lets the rear wheels – yes no four-wheel-drive here – have to minimize wheelspin. The induction process has liquid to air induction to keep that air going to the intake manifold cold and to make sure that you can take on Vin Diesel in the next Fast movie, it re-routes the air-conditioning air to the charge cooler to reduce temperature by up to seven degrees Celsius. I told you a lot of wizardry has made this car into what it is!
I can go on forever as to what the car will bring but the only way I can make this make sense to you is to urge you to click on the link at the end of this article and see for yourself what we are talking about. This is a street legal drag car which was the idea when the team at Dodge decided to do a marathon omnibus of all the race movies ever made including Fast and Furious. Ironically and for what it’s worth, it’s been banned from the drag strip by the American NHRA (National Hot Rod Association) as any vehicle that can complete the quarter mile in under 9.99 seconds would need a roll cage as well as some other safety measures that could be done in house, but I’m sure that Dodge is enjoying the “banned” status that it currently has.
If this is what ‘Merica is bringing to the table in terms of what can be done with some trick computers and some raw power, to the other manufactures across the Atlantic, your serve!
Watch the video here: https://www.youtube.com/watch?v=3vD6A6NxySQ
Do you remember that one tough guy at school? Yes him. The one that had six or seven brothers and all of them were untouchable! The brothers that were tighter than industrial super glue and if one of them got into trouble, you had to deal with all of them.
Well in a modern sense, that is what has happened to the Mercedes AMG brothers. All of them are a force to be reckoned with but together, they form the vehicular equivalent of the Avengers. The latest of the Mercedes brothers to get the in-house horse power treatment is the GLC and before you say, “but hang on we know that this variant has the uber smooth V6 270K 520 NM 43 version”, you would be mistaken! Mercedes AMG has now come out with a 63 version of the GLC. Yes, the motor that sounds like Zeus coming down from Mount Olympus, has now being shoehorned into this this Midrange Mercedes SUV. Claimed figures from the 4.0 liter V8 twin turbo is quicker that your five-year-old daughter asking, “Daddy (mommy in my household) is that a Ferrari?” That’s four seconds just FYI.
The “regular” version will get the “standard” 350 KW and 650NM and the S version will get then 375KW 700NM upgrade. In this vehicle, little Hannah won’t even get to finish her sentence at 3.8 seconds. This torrent of power and torque will be send through the familiar 4Matic system, aided by a rear limited slip differential, guaranteed to make those trips to the shop VERY entertaining.
With the GLC 43 starting at R 1 070 900.00, we estimate that you won’t get much change for your R1.7M. Competition will be tough with direct opposition from the Porsche Macan Turbo, Jaguar SVR and the upcoming Zebra stripe wearing BMW X3M. With SA’s economy hitting junk status, the older brother GLE might be out of range so this will be a steal under R2M!!
It would seem that Ford’s baby hot-hatch is quite a lot hotter than we had originally anticipated, with the recall that affected 4 556 Ford Kuga’s making use of the 1.6-litre GTDi EcoBoost motor now trickling down to the Fiesta ST which makes use of that very same motor. This comes mere moments after Ford issued a press release noting that 63% of the affected Kuga’s have been tended to.
The expansion of the recall affects some 1 078 Fiesta ST models, produced between September 2012 and December 2014. This makes one wonder, then, what change was implemented to models produced from December 2014 onwards and, more importantly, for what reason these changes were put in place…
In their statement, Ford SA said: “a lack of coolant circulation could cause an engine to overheat, resulting in a crack in the cylinder head. A cracked cylinder head can result in a pressurized oil leak. Oil that comes into contact with a hot engine surface increases the risk of a fire in the engine compartment.”
To resolve this, affected vehicles will receive hardware and software upgrades, consisting of the fitment of a coolant level sensor with supporting hardware and software changes, free of charge to customers. These parts will, however, only be available by the fourth quarter of 2017 which could mean a toasty winter for many a ST charna. Boets will all be informed as soon as they are able to book their cabbies in for repairs.
Ford say that these vehicles are safe to drive, however, at the first signs of overheating, be it warning lights or rising coolant temperatures, the vehicle should be pulled to the side of the road, debussed and the engine compartment left closed.
Owners are also urged to conduct regular inspections of the cooling system and should endeavour to maintain a 50:50 coolant-water ratio as an added precaution.
In the event of an emergency, emergency services should be contacted immediately, followed by Ford’s Roadside Assistance (0861 150 250) a service which is available 24/7.
Polo 1.0 TSI R-Line vs Ford Fiesta 1.0 EcoBoost Powershift in South Africa
The newly launched Volkswagen Polo 1.0 TSI R Line is a nifty little thing. The exterior look of this car is one that will pique the interest of many buyers. It’s marketed as a “performance” Polo despite it only having a 1.0 litre engine with 3 cylinders, but after driving it we can confirm that its nippy. The question then for you as a buyer is what’s the better buy, this new Polo TSI or perhaps the also-very-good Ford Fiesta 1.0 EcoBoost PowerShift Titanium?
The Ford has been around for a while as consumers have loved the 3 cylinder 1.0 litre EcBoost engine it offers. With 74kW and 170Nm, the little Ford produces good numbers for both city and open road driving thanks to turbocharging. Equipped with the 6 speed PowerShift gearbox, it makes being stuck in traffic bearable since your left foot can rest. The Volkswagen Polo 1.0 litre TSI R Line has similar figures in terms of displacement and forced induction. It too has 3 cylinders but produces more power with 81kW and 200Nm. The difference is not huge but will be felt by keen motorists who love to drive in a hurry. Since both these cars have tiny engines, you wouldn’t be wrong to assume that they would be frugal on fuel. The Fiesta has a great claimed combined fuel consumption figure of 4.9 litres/100km, but the Polo edges ahead with a claimed figure of 4.4 litres/100km, again very closely matched.
In this segment, aesthetics play a huge role as cars like these are aimed at youthful individuals and let’s face it, the youth “like things”. In that case then choosing between the Ford and the Volkswagen may be a challenge as they both look great. The Fiesta has ST bits on it, making it look nice and sporty. The Volkswagen on the other hand comes equipped with the R-Line package, giving it too a racier look. On the inside is where the Polo has the slight upper hand as the cabin layout is simpler whereas the Fiesta is a bit too busy. Both cars offer connectivity such as Bluetooth and USB as well as auxiliary input. The new infotainment screen on the Polo is the nicer of the two but Fords SYNC system is quite good to use as well. In terms of overall appeal, the cars are again closely matched but the Volkswagen has a disadvantage. The fact that there are so many on the road may make the car seem more “common” but the R-Line kit can set it apart. Both cars are also four doors so they’re on par when it comes to space and access into the rear.
The spikey nature of the Fiesta has always been something we’ve enjoyed about the car, it’s an engine with character. As mentioned having an automatic gearbox makes the car easy to live with day to day, so it will be a dream in the city. The Polo however is more of an angry little car. The DSG gearbox in the car has changed the character of the vehicle, giving it an immediacy that’s quite surprising. The way the VW handles too is something you don’t expect from a little 1.0 litre car. The Fiesta will be the one you want if you’re of a more relaxed disposition, whereas the Polo wants to have more fun.
Both these cars are great vehicles indeed. At the end of the day it all comes down to preference and of course price. At R290 000, the Volkswagen Polo 1.0 TSI R-Line is not exactly cheap, the Fiesta 1.0 EcoBoost PowerShift Titanium comes in cheaper at R274 900. That price tag comes with a 4 year/60 000km service plan which is a good deal. The Polo only comes with a 3 year/45 000km service plan. So what will you buy? These cars are marketed differently but offer very similar specs. If you’re more of a thrill seeker, we recommend the Polo, but if you want to save some bucks and still have a banging little cool car, the Fiesta is a very good choice too.
In my mind, Audi’s RS5 has always had a unique appeal in the very sporty small coupe segment. While BMW’s M3 has always been the nimble and dynamic youth in a hoody and Mercedes-AMG’s C63 the grandpa in All Stars, the last generation RS5 suffered from an identity crisis and was neither supremely comfortable nor tekkie squeaking fast, but it was one of those cars that you wanted and preferably without a roof.
The same could be said for each of the above’s fan bases with the Audi, again, sucking hind-teet while the C63 and M3’s were scooped up by young millionaires and old folk recapturing their youth. Every time I see an RS5, I struggle to place its driver into a category and be mean, but is this such a bad thing?
Stereotyping aside, the RS5 was great when it launched 7 years ago, a time when the E92 M3 reigned supreme and grandpa sported a 6.2-litre masterpiece in his AMG All Stars. The RS5’s 4.2-litre V8 was a meaty and burbly unit and as a whole, the RS5 was the weapon of choice for those who preferred to be discreet, yet dashing. Unfortunately, on the performance front at least, the RS5 has been left behind in recent years by the turbocharged F82 and W205.
Fast forward to 2017 and the new RS5 has again befallen the recently tabooed fate of all engines – downsizing. Harkening back to the days of the B5 RS4, the all-new RS5 sports a 2.9 litre doubly force-fed V6, putting out an M3/4 Competition Package matching 331 kW and 170 N.m more than the old naturally aspirated V8 at 600 N.m. This should be good for a 3.9 second 0-100 km/h sprint, accompanied by one of motoring’s all-time favourite soundtracks, an Audi V6. The motor is in fact the same unit found in the new Porsche Panamera, and will undoubtedly blend performance and economy in a typically Germanic and clinical fashion.
While the engine is big news, the indistinguishable crowd of people who buy RS5’s will perhaps swoon over its blacked-out LED headlights, beefy bumpers and oval holes that house the exhausts. It’s actually 17 mm wider than the model it replaces yet 60 kg lighter which is about as much as a fat child. Accompanying the reduction in weight is a multi-link suspension set-up at the rear which replaces the trapezoidal-link from the previous model.
Consumption is also vastly better than before with a claimed combined average of 7.2 l/100km.
There’s no word yet on local availability or pricing but a good guess would be the first quarter of 2018 for a million and a bit.
Rewind 20 years and anyone claiming to have had a vehicle with a 1.0 – litre 3-cylinder motor producing 81 kW and 200 N.m would have been labelled a madman. If they were to continue, stating that this revolutionary vehicle would sip just 4.4 l/100km and exhibit refinement to match the then contemporary E39 5 Series, the automotive community would have locked them away in a Corolla in solitary confinement until they came around.
Having now grown accustomed to the trend of downsizing, most of the above doesn’t really come as a surprise to both the public and motoring scribes alike. What does come as somewhat of a surprise is that the vehicle boasting all of the above figures isn’t even a brand new vehicle, but rather an updated version of a car that’s been on sale in South Africa for the past 8 years. There’s no denying that the Volkswagen Polo is the most impressive vehicle within its segment and now it has been given quite a nice little final hoorah if you will.
Its full name is the Polo 1.0 TSI R-Line and it features VW’s hugely impressive 3-cylinder 1.0-litre unit, mated to the 7-Speed DSG gearbox we’ve come to know and love. Along with its the drivetrain, the Polo has also been visually tweaked with a smattering of R-Line goodness in the shape of R-Line design front and rear bumpers, R-Line sill extensions, a rear diffuser, chrome exhaust tip and 17” alloys. 8 years on, the Polo is still a handsome thing and while the interior on this model is much the same as the rest of the range, it remains a superlative example of build quality and tactile pleasure.
Set to make its way into a number of VW Group Products, the 1.0-litre unit features active balancing shafts which cancel out the inherent vibrations within a 3-cylinder motor. It’s a very smooth unit which delivers maximum torque from just 2 000 rpm. Due it being lighter than the locally produced 1.2-litre unit alongside which it is offered, it’s a free-revving and spritely motor and is surprisingly characterful thanks to the triple thrum emanating from behind the bulkhead. A claimed consumption of just 4.4 l/100km is 0.5 l/100km less than that of the 1.2-litre motor, yet 25 N.m more torque is on offer.
While pottering around town, the low-down torque and the slickness of the DSG transmission really do make it all a bit effortless and brisk bursts between traffic lights actually bring a smile to one’s face. Dynamically, the chassis handles the twisties with aplomb and the sometimes rough and constantly undulating roads along our test route in the countryside of Port Elizabeth were where the Polo did better than expected. Its high-speed stability is far superior to that of its competitors and again, this is all thanks to a well-sorted chassis and incredible refinement, as well as the use of Volkswagen’s XDS Electronic locking diff which you can certainly feel doing its bit in the corners and comes as standard on this model. If I were to briefly sum up how the Polo drives, I would have to say that it is confidence inspiring and effortless, and can be different things to different people. The R-Line package adds an impressive duality to the Polo in that it can be sporty and playful if that’s what you ask of it, as well is comfortable and docile if its economy and a leisurely drive you’re after.
Other standard features include the usual raft of safety features, rest assist, 4 airbags (6 optional), air-conditioning, multi-function steering wheel, Bluetooth connectivity, sports seats with drawers beneath them and a front-centre armrest with storage compartment.
Priced at R290 200, it comes in at the same price as the already available 1.2 TSI Highline Auto but offers a different box of frogs to that vehicle. Yes, it is rather pricey, but you certainly get your money’s worth – just remember that if you were to tell someone in 1998 that your Polo would be able to match their 523i in all but size and thirstiness, it’d be back to the Corolla for you!
In days gone by, Mercedes-Benz were the last word in refinement. Silky smooth straight sixes were the order of the day and while slightly less practical to package than a V6 motor of equivalent capacity, the inherent benefits of a straight six over a V6 made it worth the long bonnet. Because people hate long bonnets.
It would seem, however, that BMW are the only big manufacturer to produce straight six motors these days. Ford Australia did for a while, but they don’t exist anymore and neither do TVR…
This is strange because while a V6 motor makes packaging a breeze thanks to its compact dimensions, it becomes very complicated due to the inherent vibration issues caused by two banks of cylinders with yaw moments on different axis. Balancing shafts can easily cancel out these vibrations but this means that more inertial mass is required to spin the engine – ie: you need more power.
The great news, then, is that Mercedes-Benz are back on the straight-six train as announced towards the end of 2016 and the new M256 promises to be a powerhouse of note. A part of their new range of modular engines, the new six will arrive alongside petrol and diesel straight-fours, straight-sixes and a petrol V8. They all have identical bore spacing and interfaces to vehicle which cuts production costs.
Back to the M256, it features a host of new technology, most notable of which is the Inline Starter Generator or ‘ISG’. The ISG is a 15kW electric motor which drives the crankshaft, starts the internal combustion engine when start/stop is enabled, recovers energy during coasting and braking and acts as a generator for the 12v electrical system. It can also reduce the load on the engine which aids performance and economy.
It is also part of the 48v electrical system which comprises an electric air-conditioning compressor, electric auxiliary compressor and electric water pump which means there is no need for a belt-driven accessory drive. This means that engine length is reduced which, as I have already mentioned, causes packaging issues with the straight-six motor.
Another brilliant up-side to the whole electrification thing is that the 48v compressor is essentially a supercharger which doesn’t have a parasitic effect on the combustion engine. So at low RPM’s, the compressor kicks in and provides boost up until the big exhaust driven turbo kicks in. Expect figures of around 304 kW (407bhp) and 501 N.m and remarkable efficiency, we hope.
Expect to see this exciting new motor in the updated Mercedes-Benz S-Class before trickling down into the rest of the Mercedes-Benz stable.
Gas flowing, or porting of cylinder heads, is viewed by most laymen as being more mysterious than the US foreign policy. What does it actually mean? How is it done? Does it even work? Of course, there’s no short answer. But hopefully, this article will serve to clear the murky waters somewhat.
The function of the cylinder head, and the inlet ports in particular, is to introduce air from the inlet manifold into the combustion chamber with as little restriction as possible, and hopefully take advantage of the velocity of the fast moving air in some way. The exhaust ports must do the same as they get rid of the burnt products of combustion.
Now, a mass produced cylinder head will have ports which are left “as cast”, so they have a rough finish and various casting flashes which will all cause a disturbance to airflow. They will also often be of a less than optimal shape. This is particularly true of the older designs like the Ford Kent Crossflow or cast iron Chev V8 heads, which have all sorts of undesirable lumps of metal in the wrong places. And you only need a brief glance at an MGB head to see that it’s about as free flowing as a blocked drain. So, with these older heads, it’s a relatively simple matter to remove the offending lumps, and gain a heap of airflow. This is normally done with a pneumatic handheld porting tool or die grinder turning at 5 or 6 thousand RPM, and is extremely easy to make a complete mess of, which would result in the cylinder head being chucked in the bin. For this reason alone, it’s worth leaving it to a professional cylinder head shop. Outfits which habitually do large numbers of the same heads might CNC mill the ports, but in this country, we never see these volumes, so it’s all done by hand.
Generally, after removing metal with an abrasive mounted point or tungsten carbide burr, the ports are polished with fine grit sandpaper, again mounted in a die grinder. The ideal finish of the ports is the subject of much debate – some tuners prefer to leave the intake ports slightly rough, and some prefer a smooth, almost mirror finish. Bench testing seems to indicate there is not much difference to airflow either way.
But what about the size of the ports? Does it make sense just to make them as big as possible before one goes right through the port into the water jacket? No. There is definitely an optimal size, based on the intended speed range of the engine, the capacity of the engine, the valve head size, the camshaft, carburation, etc. In fact, some standard ports are already too big, and more adventurous tuners have filled in these ports with special epoxies. The problem with very large ports is that gas speed drops as a result of the increased port area, and bottom-end power suffers. This may not be an issue in a racing engine which never goes below 4000rpm, but it certainly is in a road car.
The shape of the port is equally important. Material may need to be removed in some places and not in others. Generally one would try to “straighten out” the port as much possible, removing material from the roof of the port and leaving the floor more or less untouched. The area just below the valve seat, called the throat, is also important as it needs to accelerate the gases as they enter the chamber, taking advantage of the venturi effect caused by slightly reducing the cross sectional area of the port just before the exit into the chamber.
The valve seats are then cut using a specialised machine (usually known as a Serdi), giving it a smoother profile and a narrower valve seat which will aid gas flow at small valve openings.
The valve itself is also reshaped to aid gas flow – a particularly critical area, as all the gas must pass over the back of the valve. If one compares a typical valve from 20 years ago to a valve from any modern high-performance car, it is obvious how much development there has been in this regard.
So if all this works on older cars, does that mean it doesn’t work on newer engines? No, of course, it works; it’s just a bit harder, and the gains may not be as big. And if the application is totally different, for example, building a full race engine from a normal road car engine, then bigger valves and bigger ports will be needed to allow the engine to breathe at the higher RPM it will be operating at. There are some exceptions, like an E90 M3 V8, for example, which has big, beautifully-shaped CNC-machined ports, which most sane tuners wouldn’t dare touch.
Measuring the changes in airflow can be done using a device called a flow bench, which measures the flow rate of air through a port at a constant vacuum. It provides a useful yardstick, but is by no means a sure way of predicting the power increase, as the actual conditions in the engine are quite different to what is happening on the flow bench. For example, the vacuum in a combustion chamber is nowhere near constant. It’s also a very time-consuming exercise. And there’s always the infamous story, no doubt greatly exaggerated by now, of a 1950s works Jaguar Le Mans team, which measured each gas-flowed six cylinder head on the flow bench and obviously kept the higher-flowing heads for themselves, selling the others to the customer teams. Imagine their surprise when the customer cars turned out to be faster than the works cars down the Mulsanne straight! Back to the drawing board…
There are other aspects to gas flowing or modifying a cylinder head; one may want to impart a circular motion to the gas as it enters the combustion chamber which will aid cylinder filling. This is known as “swirl”, and is most often associated with 2 valves per cylinder heads.
Obviously, this subject could have several postgraduate theses written about it, so it’s only possible to lightly scratch the surface on these pages, but hopefully it’s enough to enlighten the average armchair enthusiast. Just don’t be tempted to get out your Dremel and start hacking away at your ports on the weekend…