2015 Bahrain GP Tech Highlights

Given that the gap between the Chinese and Bahrain grand prix was just one, tweaks to the cars were minimal and were mainly aimed at cooling as the two circuits share quite similar downforce characteristics.

However more was learnt about McLaren’s Honda power unit plus a few other additions were also visible over the course of the weekend.

McLaren (Quoted is from my piece for Richland F1)

“A lot has been disputed about the underlying technical details of Honda’s 2015 powertrain. What we have already established is that they are indeed utilising the split turbo concept that Mercedes pioneered last year, with the exhaust driven turbine and the compressor being separated by the MGU-H that sits in the V of the engine.

However, information remained scarce for some time as to how they were cooling the compressed air until the beginning of April, when it was revealed that McLaren run an air-to-air intercooler in the right-hand sidepod. This therefore meant that the radiator – uniquely placed above the engine itself and fed by the top inlet in the airbox – is used to cool the ERS package. This opened up space to pinch the bodywork inwards, tapering tightly into the “size zero” Coke-bottle region at the back of the car.

Recently, more details have been uncovered about just what McLaren are doing with their power unit to allow such tight packaging with relatively little cooling requirements. Although they are still running quite a large central outlet at the back, the overall area of openings made into the car is pretty minimal relative to the rest of the grid.


It transpires that Honda have developed a totally different compressor side to the turbo than any other manufacturer. The regulations do govern this area quite strictly which is why Mercedes, Ferrari and Renault have all converged on the same solution. Honda on the other hand have been a bit different.

The rules state that the compressor must consist of only a single stage, so the general consensus is to use a large centrifugal fan to draw air in through the airbox and onto the intercooler. The larger the fan the higher the boost pressure achieved although this is not such a big tradeoff when considering the fuel flow limit. A smaller fan, though, will spool much faster due to its lower inertia, which improves drivability.

Honda have opted to use a much smaller, axial compressor but without the multiple fan elements that would make the system illegal. Instead there is one elongated fan that stretches across a narrow tube, with perhaps a multitude of increasingly sized blades to guide air through.

There are a number of advantages in doing this: the resulting smaller compressor can be packaged neatly into the V of the engine alongside the MGU-H, removing the blockage created by a large centrifugal fan and bumping the engine up closer to the fuel tank. The emphasis on doing this is to again create more space further behind and improve the weight distribution of the car.

Secondly, a smaller fan naturally spools much faster which places less reliance on the MGU-H to generate boost under acceleration so energy can be saved instead for the MGU-K – a more dominant player in terms of laptime and an area in which Honda have struggled to make inroads in so far. Once reliability problems are sorted in this area we could see the partnership making large strides in energy recovery and deployment later in the year.

To make room for the top mounted radiator, Honda have had to create a low-lying inlet plenum which is made from aluminium rather than carbon fibre. This will have been done to resist the transfer of heat from the radiator above and also to make a more suitable shape in a crowded area. With the introduction of variable-length inlet trumpets, I imagine that this was a pretty tough component to produce.

Overall, it is these detailed changes that Honda have implemented that will eventually aid McLaren’s aerodynamic package. Once the MGU-K seal gremlins have been overcome and the power output rises further, only then will we see the true potential of the MP4-30 chassis.”

Another possible theory is the use of Honeywell’s DualBoost turbocharger, which is technically a type of axial compressor. It also utilises two inlet pipes for the compressor, with the exhaust-driven turbine spooling two fans that face back-to-back of eachother before combining the charge air into one pipe to be fed onto the intercooler. It’s a smaller solution than a conventional centrifugal fan thanks to the dual fans, so it could squeeze into the V of the engine.

Aside from the power unit, the MP4-30 featured some small aerodynamic adjustments.

Gone is the innovative ‘tubercles’ rear wing upper flap and in its place is a traditional straight-cut leading edge. The idea behind the tubercles flap was to improve flow attachment as the DRS closed (more on this here) but clearly – with a host of new faces within the McLaren aerodynamic – there has been a change of philosophy and perhaps some subtle detail work done elsewhere to improve efficiency in this scenario.

Modifications were also made to the rear diffuser. As well as upwash, the diffuser’s outer walls expand airflow out from beneath the floor, too, to suck the car further into the ground. McLaren have tweaked this area to improve this effect, which has also resulted in reducing the number of fences from three to two.

Red Bull


After introducing a new front wing in China, another small tweak was made to the endplate in Bahrain.

The red line represents the China update, with the arched section now more pronounced than before and pushed slightly inboard than the previous specification. The old wing’s arch was pushed right up against the endplate, so this change in philosophy follows more of a Mercedes pathway.

Highlighted is the new addition – a small pressure gradient vane that has become pretty common on the cars this year. The vane will cause a small low pressure zone behind, drawing air out from behind both the underside of the wing and from behind the endplate at a faster rate. This is another outwash aid which, combined with the blown front axle and the underbody effect of the wing, should help improve flow management around the front tyre.

2015 Chinese GP Tech Highlights

Note: Due to a lack of time (as explained in my Announcements 5 blog post) most of this has been copied off my analysis piece for Richland F1, with some added extras that I worth noting.

Shanghai is a bit of a tricky track to set the car up for as the corners are predominantly medium speed with long traction zones (especially the large banked turn onto the huge back straight), but there are plenty of straights to make up time on.

It is for these reasons that we tend to see a compromised aerodynamic package which will later be seen in races such as Canada, where the trade-off between downforce and top speed is constantly being assessed throughout the weekend.

The lengthy corners also put a focus on front tyre life, particularly the front left, so you can’t take too much wing off the car or else you risk putting the tyres in jeopardy. Even if you have slightly too little downforce the tyres won’t stay in their optimum temperature because the straights cool them down before the driver even reaches the braking zone – you could say that it is one of the toughest rounds of the year regarding setup.

To solve these problems teams bring upgrades, which are ideally more efficient at producing downforce than the outgoing component.


As promised by Mercedes, an array of new parts made their way onto the W06 right from FP1 after being beaten by Ferrari two weeks earlier.

W06 FW China

Front wing development has stabilised slightly over the past season but this new wing has once more upped the game by introducing an even more aggressive outboard region concept.

The elements – which remain at a total of six – arch aggressively at the extremities of the wing to form two distinctive sections: the inboard and outboard. The inboard is composed of the main plane which is split into two planes, and the upper two flaps and these are responsible for creating the Y250 vortex and controlling airflow around the front suspensions members.

Outboard, Mercedes have further expanded on the vortex tunnel design by almost isolating it entirely from the rest of the wing. The leading edge of the tunnel is shaped such that the air curls over on itself and accelerates. This coupled with the introduction of higher pressure flow through the slot gaps on the upper surface of the wing coils up the air to form a powerful vortex that is shed around the front tyre. This generates a huge amount of downforce and helps the endplates push flow around the front tyre too – the outwash effect.

These vortices tend to break up once they have come around the tyre as the turbulent wake behind the rotating wheel mixes with it and disperses. Contrary to popular belief these vortices never reach the Coke-bottle section of the car – the designers want to keep this area full of clean laminar flow to work the top of the diffuser, which is why we see the large vanes the hang off the shoulder of the sidepods to protect air passing through the ‘pod’s undercut.

Additionally, more tiny vortex generators on the individual planes of the wing were also evident. Again, this is to help air pass through the slot gaps and aid how the main vortex in the tunnel forms.

Mated with the new wing was an updated pair of front brake ducts. The previous large vane that hung off the guide plane of the duct has been deleted in favour of a more fluid-looking flick-shaped vane that branches neatly from the leading edge of the duct. This will work more favourably with the updated front wing.

As mentioned above, top speed is also important in China so a revised rear wing was also brought in. The wing has a slightly lower angle of attach and the wing tips cut triangularly to reduce drag.

Red Bull

Renault’s power deficit was always going to be more evident here than any other track so far in 2015 so Red Bull had a number of rear wing options to play with. A lower angle of attack version was used by both drivers during qualifying and the race, both of which feature their more intricate endplate design with the extended slot along the leading edge.

On the front wing, the Milton Keynes outfit have now officially departed with their long-standing endplate design in favour for a Mercedes-style solution, featuring a single fence with a small flick at the trailing edge to entice flow around the front tyre.

However the most important change Red Bull have made so far this year is returning to Brembo discs and calipers from China onwards, swapping out the Hitcos used since winter testing. The team opted to use Hitco at the start of the year following Sebastian Vettel’s feedback before he headed off to Ferrari, but cooling issues have resulted in them being ditched in favour of what they has last year.

The Brembos work like no other brake on the grid – they are not the most powerful but they are extremely consistent across the braking phase. However they also require less cooling inlets and are generally easier to manage than most of the other manufacturers out there, which is why we saw the issues the team had in Malaysia.

Swapping back to another brake supplier is pretty difficult, though. Daniel Ricciardo was having visible difficulty to stop the car during the race, which can be put down to the team not finding the sweet spot between the brake bias and the pressure versus the harvesting capabilities of the MGU-K. It’s more of a setup issue than an inherent car problem, so expect it to be addressed soon.


C34 FW

Like Mercedes, Sauber also had a front wing/front brake duct update. The new wing is a quite the departure from its predecessor as the promising C34 begins to undergo significant development.

Designed during early 2015, this wing was meant to be introduced in Bahrain but it was fast-tracked thanks to funds coming through quicker than expected.

Whilst the cascade winglet remains very much the same as the last edition, the accompanying ‘r’ vane has been moved closer with a small aerofoil join sandwiched between them.

The wing itself has been upgraded from four to five elements, with a more conventional divide between the inboard and outboard sections similar to that of Mercedes. Metal clips have been formed into the carbon fibre at the inboard region to stiffen up the wing as it undergoes load, allowing for a more consistent formation of the Y250 vortex across a range of speeds.

It is worth noting that the flap adjuster lies on the inboard section. More commonly this housing is placed on the divide between the two regions as this is more aero neutral. However keeping the outboard segment cleaner can certainly benefit the overall outwash effect of the wing and is also slightly more efficient.


Some subtle changes were made to the Lotus front end, minutely changing the aerostructures to suit components downstream.

The nose pylons were extended downwards at their base, removing the transitional step between the pylon itself and the wing’s mounting bracket to form a smooth profile for air to pass over.

This was accompanied by a small adjustment to the inboard flap section that is responsible for controlling the Y250 vortex. These were extended further inwards and curled down towards the main plane in a similar fashion to those on the Mercedes. However this this wing configuration was not raced on Sunday although expect it to turn up in Bahrain this weekend.


For all the raving about Williams’ front wing during the weekend, it appears as if it was just a minute alteration to the under-wing turning vanes that was the only visible sight of anything new.

But do not let that fool you so quickly. So much work is done through the layup of carbon fibre that has a dramatic effect on how the wing performs across all air speeds. Williams are one team in particular who are ‘bending’ the letter of law with some extremely flexible wing flaps, as evident on the onboard nose camera shot. Getting the wing to flex in a desired manner can be worth multiple tenths of a second per lap when working correctly. Expect this to be an underlying feature of the 2015 season as the designers run out of areas to play with.

Announcements 5…

I have been generating content for this blog for just over two years now and I have already gathered a significant following. I have enjoyed, and still do enjoy, writing on here and expressing my knowledge (which increases all the time) of engineering in motorsport and I hope you also like my content.

However lately I have had to take a bit of back seat from the blog and F1 in general. You may have noticed I’ve been less active on social media as well.

I still love the sport and the technical side always excites me but I am struggling to find time to juggle a social life, earning a bit of income to pay for that social life, studying at degree level and – most importantly – finding enjoyment out of all of these things.

This all means that I have much less time to write on here. This is also due to an underlying feeling of a lack of motivation at the moment – we all go through it and hopefully I’ll be fired up again fully in the near future.

I continue to religiously watch all the races (as I have done since 2007) because at the end of the day I fell in love with F1 as a fan, not as a journalist. The same applies to all the good journalists out there because they apply emotion to their writing that others simply can’t translate.

It’s gutting because I don’t like not posting on here, I promise you that! My blog is my pride and joy and it has propelled me to places I never thought were possible in motorsport journalism and we’re just scratching the surface…

Ultimately my ambition is for other people to be writing about what I have designed on the cars and to reach that I have to prioritise things. So this is just an announcement to say that there will be less on here than normal for now as I get on top of things.

I have promised an LMP1 car comparison piece between Audi’s 2015 R18 e-tron quattro and Nissan’s intriguing GT-R LM NISMO, so I’ll get that sorted soon! But for the time being it might just be Technical Highlights posts only, plus a bit extra for Richland F1 as they are fantastic website heading in a strong direction.

I hope you appreciate this decision.


Silverstone Single Seater Driving Experience


Not a tech related post but I thought I’d share this with you.

As some of you may know, my parents gave me a single seater driving experience at Silverstone for my 18th birthday, all the way back in 2013! Unfortunately – thanks to the miserable British weather about 90% of the time – it took me three attempts to complete the damn thing: the previous two occasions had been called off due to excessive rainfall and poor visibility. Continue reading

2015 Malaysia GP Tech Highlights

Traditionally the Malaysian GP comes just one week after the opening round in Australia. However this year a two week gap has allowed teams to fine-tune their cooling packages ahead of what is one of, if not the most challenging places to race a Formula 1 car.

Impressively, most teams managed to retain a relatively tight rear end despite track temperatures peaking at 61.4 degrees Celsius. If we compare how open the bodywork was this time last year there is clear evidence that this year’s power units are another step forward in terms of efficiency. Closing up bodywork reduces drag and allows the aerodynamics to work at their maximum potential, rather than being disrupted by hot air vents and larger outlets. Continue reading

2015 Australian GP Tech Highlights

The opening round of the season in Melbourne produced few technical upgrades, although most of what was brought to the final test session was intended for the opening races of 2015. Whilst we can expect a few more bits for Malaysia, this Technical Highlights post runs through a couple of the larger developments from the teams from the final Barcelona test and the minor detail changes made for Australia. Continue reading

The Mercedes W05: How it dominated in 2014 – Part 2


Part 2 of mine and Matt Somerfield‘s eBook on how the Mercedes W05 dominated in 2014 is available to buy on the Google Play store for just over £4. It explains all the aerodynamic details of the (statistically) most successful F1 car to date and also runs over topics such as FRIC suspension (pictured above). Please purchase it – a lot of effort went into this part of the eBook so we would really appreciate your support.