Toro Rosso have perhaps introduced the biggest update package of all teams at Barcelona, with the STR8 now being fitted with a new ramp style exhaust. The team have however not exactly copied any of the existing designs but instead opted to go their very own way and come up with a very special ramp.

Previously the team had an exhaust more similar to that of McLaren, but the new version should help draw the exhaust gases down better, or at least in a more controlled way. Just like with Lotus and Red Bull, the sidepod included an undercut that helps channel air underneath the sidepod onto the central part of the diffuser. The particular thing here is that Toro Rosso's channel is entirely open while all other versions feature a closed channel. As this is of course the initial version on the STR8, more development in this area is likely to appear in future races.

Feedback from the drivers is already positive, with both saying the car is much more stable and easier to setup.

McLaren have pinpointed their problems of 2013 to a problematic correlation of wind tunnel data and struggling to get a persistent airflow around the Pirelli tyres, which are now flexing differently than last year. Jonathan Neale even likened their problems to those at Ferrari last year, saying the Scuderia people will surely know how it feel to be in the position McLaren is currently in.

As a first step to resolve some car problems, the team introduced a modified sidepod panel that now features a bridge to connect to the shoulder of the sidepod, similar to what can be seen on the Red Bull RB9 and by now on various cars. Although not perfectly visible on the image, the bridge is actually quite thin, with a much shorter chord than the vertical panel actually is.

In the same move, the vortex generators on top of the sidepod are back, reverting from the horizontal winglet that was copied from Lotus earlier this season.

Caterham have introduced the second part of their major upgrade package for the CT03 which should help the team get ahead of Marussia again. Part of the update package was moved forward and introduced on Charles Pic's car in Bahrain, including the bulge under the nose, revised rear wing endplates and the new sidepod panels.

This time around, the focus was mainly on the front end, with a raft of updates aimed to help increase front downforce. The most obvious change of course is the vanity panel on the upper side of the nose which now hides the ugly step. Although this is likely to give only a marginal aerodynamic improvement, it's still a big improvement to the eye.

More importantly for the car's efficiency is the new front wing that finally ditches the unconventionally big stepped element, replacing it for a wider, shallower 2-element winglet similar to what other teams feature on their front wings. The main panels have also been revised, with notable changes on the inner edges and a smaller slot gap between the wing's base and the first flap.

Furthermore, the brake ducts have been revised to add a vertical fence that extends further forward and new turning vanes appeared under the nose, now more similar to the designs of Red Bull Racing and Ferrari.

After rumours emerged in the Italian press about RBR's alternator, Renault Sport have now confirmed to F1Technical that Red Bull Racing is indeed using a McLaren Electronic System alternator in combination with the Renault engine. The firm notes this is the case "for some time now", with all other Renault powered teams still using the Magnetti Marelli alternators, similar to last year.

Renault's technical director, Rob White, says this is the result of the problems during 2012: "We suffered unacceptable recurrent reliability issues with alternators fitted to the RS27-2012 engine that we supply to all our teams. At Renault, we take full responsibility for the design and integration of the engine and ancillary equipment supplied to our teams, including the alternator. We worked with the support of our teams and suppliers to develop countermeasures to eradicate last year’s problems. The work was underway before the end of the 2012 season. It was completed during the winter and validation was signed off in pre-season testing. These solutions have been implemented on alternators for all of our teams and we continue to monitor the situation closely."

While having two different alternator options now fitted on the RS27-2013, Renault also pointed out that the options to pick are still in Renault's hands, and that two alternatives are now available due to differing electrical requirements on different cars.

"The alternator generates electrical power to match the electrical consumption of the car and to maintain the charge of the battery. For chassis reasons, the electrical power requirement may vary between different types of car. In parallel to addressing the reliability issues experienced in 2012, and having consulted all our teams, we have increased the electrical power capacity of our alternators. To manage the technical and logistic risks, we have worked with two suppliers for the electro-magnetic components to provide alternator parts to our specifications. Responsibility for alternator supply to the teams and supplier choice for all components and assembly operations remains with Renault."

The options appeared to have paid off, as no issue was found on any car so far this year.

Despite only having a 7 day gap since the Chinese GP, Ferrari have brought another update to their F138. The team fitted new sidepod panels on both their cars during the entire weekend, increasing the volume of the sidepod around the UPS logo. The difference is clearly visible when you focus on the joint of the foremost panel - with the Shell logo - that was unchanged and the new panel with UPS on it.

The previous design had fairly visible downward ducts, still somewhat similar to their "Acer duct" naming of 2012, although they would now have to be called "UPS ducts". Now, the underside of those ducts has been beefed up. While it is hard to say what exactly the team is aiming for, it is possible that Ferrari wants more air to flow alongside the UPS logo rather than pushing it down towards the floor.

Also visible in the picture are the new shark gills close to the car's floor. These are added to increase cooling performance but are likely to disappear again at events with lower ambient temperatures.

Caterham F1 have brought the first updates to their CT03 since the beginning of the season. The team urged a few updates as soon as it appeared that there were considerably issues with the car that would make it unable to put up a fight to any other team. The updates seem to have had an immediate effect, with Charles Pic saying after free practice that the team were to adjust the car set-up as the updates immediately brought in understeer thanks to increased downforce at the rear of the car. A more comprehensive number of updates will be added at the Spanish GP in 3 weeks time.

So far, the updates were only tried on Charles Pic's car, including a new bulkier nose that copies an idea pioneered by Lotus last year to help clean airflow underneath the high nose. Sauber and Force India are teams that have followed that trend before, with Red Bull trying it on last year's car as well.

Perhaps more importantly is the new Red Bull style panel aside of the sidepod. This greatly helps control how air ends up at the back of the car.

Red Bull introduced a new beam wing on its RB9 this weekend at Bahrain. The new version will generate a little bit less downforce than the more conventional one used during the first 3 races of the season. Although a smaller beam wing it itself is nothing special, the roundings on the trailing edge of the wing are interesting indeed. The element is aimed at generating more downforce close to the centreline of the car while the reduced frontal area will cause less drag and downforce closer to the rear wing endplates.

Also new on the RB9 is the different cut-out on the central hot air outlet, aimed at keeping the car's internals at acceptable temperatures in the heat of Bahrain.

Red Bull Racing have copied Williams' hollow front wheel axle and wheelnut to allow air to pass through. Identical to the Williams version that was used since winter testing, the wheel nut is empty in the middle, which allows air caught by the brake ducts to flow out in an attempt to control the front wheel's wake. The latter is an important factor for rear downforce and also explains why teams are not using a similar system on the rear wheels, where it is more beneficial to have smaller brake ducts.

The system was only seen in the Friday practice sessions on Sebastian Vettel's #1 car.

Already since the Chinese GP of last week, Mercedes are running a slightly different front wing which includes a tiny lip on top of the stacked element support.

Also marked in the image are some interesting details which show how much attention Mercedes have put into this new front wing after basically struggling with that part of the car for several years. The support for the stacked element for instance is not as simple at it may initially appear as it is clearly shaped differently long its height.

One other thing that is remarkable is the shape of the flap support, including the front wing adjuster. At most teams these are two separate element or a more solid item, but Mercedes have clearly put effort into making this item as small as possible to create the least possible effect on the airflow.

Lotus Technical Director James Allison has revealed that the team will introduce a new element in the front suspension that is mainly aimed at better controlling the ride height at the front of the car: "We will trial a suspension modification – internal rather than to the wishbones – which is an evolution of something we ran to good effect during pre-season."

Allison does not reveal what exactly will be tried, but his further comments claar up a few things: "You’re always trying to find the right compromise between the mechanical grip that the suspension’s articulation offers to the tyres and holding the aerodynamic platform at the optimum height from the road, and we believe this is a step forward in helping us achieve that."

Indeed, each team is aiming to attain the best possible ride to make sure the tyres keep into contact with the track over their entire width. Even though that is possible by softening up the suspension, doing so at the front would induce the need to raise the front as brake dive would be more pronounced. This on the other hand will adversely affect aerodynamic performance. Lotus' new system, whatever it may look like, is certainly different to the system that was banned in January 2012 but similar in its purpose. The new update is therefore either aimed to improve the frontal ride or to maining the same suspension behaviour while allowing to the run the car a little bit lower than before. Either way would help the car's performance and will raise interest from other teams if the modification proves effective enough to use in races.