Talent and Innovation are two largely, even occasionally misused words, in the current financial climate. 

Every time they are used in a conversation our minds wander, from the fascinating nuclear researches to the ultimate ultra-technologic, multi purpose remedy for humankind health.

In reality, innovation is probably better explained as “a progressive and constant improvement of every day life conditions and living/working environments”. On the other side though, we or our predecessors have witnessed how sometimes is the simplest inventions that made the biggest impact.

In this case we would like to bring to the table a very “hot” topic for those involved in motor racing. The problematic temperatures generated by brakes, typical of sport-performance vehicles.

If the most advanced (and expensive) competition machineries are fitted with water cooled brakes, or simply aided by the fresh air waiving by on single seaters, all the remaining tin-top vehicles, including modern Touring/Rally Cars, are left to face the trouble of the heat, which often compromises the performances of brakes.

Such phenomenon occurs when specific tracks or rally stages demand constant and heavy decelerations, generating a huge amount of heat in the calipers which literally “boils” the oil of the hydraulic brakes, degrading its viscosity, generating some small steam bubbles and therefore decreasing the pressure level in the system, because steam is compressible.

This is communally called vapor lock, and is exactly what happened when a driver claims he was left with no brakes during the race. The pedal starts feeling “spongy”, and in the worse scenario it goes dangerously flat to the floor when he needs to rapidly slow the vehicle down.

Technology has brought relief to this problem by equipping Aluminum Wheels to race cars for their well known capacity of dispersing part of the high temperatures in the arches. Special racing purpose rims like all the EvoCorse models are particularly indicated for dealing with such conditions.

 Unfortunately this is still not enough though, on both heavy historic racing motors and light but fast modern cars, drivers often need to either lift off the throttle for preserving their brakes, or simply take the risk!

EvoCorse, a young and dynamic northern Italian factory, which is growing notoriety among competitors with its high quality aluminum rims, has now come with the solution.

 An All-Round research program, which has seen the involvement of several companies specialized on the development of new composites and materials, has given birth to “P-DEF” (Pyroclast Dynamic Energy Filter).

 The P-Def is a rigid 1mm thick plate, it easily slips in the caliper between the pistons and the back of the brake pads, working as a barrier for the massive amount of heat generated during the race, holding it inside the caliper, creating also a better environment for the racing friction materials, which notoriously give better performances at higher temperatures.

Somebody likes it hot!

 Simple to install, it does not require any further modification of any other part in the car, and it’s 100% racing legal! Let’s see if this P-Def is only another fancy gimmick, or if it can really help.

Together with Lake Racing Team, from the picturesque Como Lake area, and the Black Devil Team from the province of Venice, EvoCorse has put together a test day at the “Adria RaceWay” Circuit. The venue is particularly indicated for this sort of experiments thanks to its twisty track. Although it cannot re-create the characteristics of a real tarmac Rally Stage, there is never much of a straight line between corners here.

For this occasion Max Busardò, head of Lake Racing which runs the Grande Punto Abarth S2000 used on track, has applied sophisticated data acquisition instruments directly to the calipers, right behind the pistons. This sensors were all connected to an on-board computer for the constant live monitoring of all the brakes behaviors including temperatures, timing and oil pressure.

During the day there was also the availability of digital and laser thermometers, used mainly on the Citroen Saxo S1600 ran by the Black Devil squad, and driven on the test by the team owner.

 Three drivers have alternated on the hot seat of the Turin’s beast. Two well known gentleman competitors in the business for years, Giacomo Ogliari and the Swiss man Zoller,  who shared the experience with a real Pro; the Italian and also European rally championships winner Giandomenico Basso, who also brought a great deal of  knowledge of the Punto, accumulated during four years works drive for the Italian manufacturer.

...while the smaller French S1600 had Alcon brakes, branded Citroen.

We waited for the early afternoon hours before proceeding with the data acquisitions, after a few morning “installation laps”, and also for taking the vantage of the warmest part of the day.

Temperatures at pit lane:

The records obtained with the laser thermometer pointing at the standing still Saxo calipers were in line with what the EvoCorse men where expecting to see, but amazing for whoever was seeing the P-Def at work for the first time, including the driver Busatto.

The test has evidenced a difference of 30°-35° less, read when the little French bomb was fitted with the P-Def. Even without the P-Def on, this two cars have very rarely manifested any overheating trouble anyway, specially on a typically mild half March day in Italy (approx. 10-12°), but the test was useful to understand just how much heat the magic plates can stop, and if it can help preserving the ideal temperature where it’s needed, rather then dispersing it, letting it go where we do not want to.

“Another story was when”, as Luca Meneghetti of EvoCorse explains, “back in 2010, during the first developments of the project we tried the P-Def on few R3 Rally cars, like the Renault Clio Rs MkIII and the Honda Civic R3. They notoriously suffer from too high temperatures, but with this new barrier we have seen differences of up to 50°!”

Moreover, by taking a look at the charts reported here below, we can notice yet one more benefit gained from the use of the P-Def system.

As we initially suspected the P-Def do not “eat” or magically make the heat disappear, but simply hold it in between the pads making them working at higher temperatures as well. This is generally not good news on road vehicles, but represents instead a better environment for racing synthesized brake pads which can now constantly give their best, even on the long course, or when we drive on long stretches between severe curves.

So far we have reported the interesting discoveries made from the use of P-Def on the little Citroen Saxo S1600.

Even more interesting, and well surprising too, was the outcome from the live on-track monitoring of the “Lake Racing Team” Abarth S2000.

We have analyzed all the datas dividing the circuit on all its bends, assigning a different letter to easily identify each corner, as the drawing shows.

For our convenience, we have analyzed for this article only the data acquisitions from the laps ran with Giandomenico Basso on board.

Temperatures:

We can note a clear difference between the datas recorded at pit stop and the continous recording on track: temperatures differences with and without P-DEF are smaller during the peak of the braking, around 10-20°C, meaning that in that moment the quantity of heat produced is so high that can pass the P-DEF barrier. But after that very short moment, the insulation effect came back and the heat filter became more efficient.

If during the peak moment of each intense braking the gaps aren’t so significant (Fig.1), it’s however interesting noticing how the external side of the calliper quickly cools down (Fig.2) on the short straight lines. This thanks to the plates stopping the extra heat popping off, which certainly would also result on “Vapour Lock” happening on such stressing conditions in many cars.

We immediately understood how P-Def is beneficial to the entire system, allowing the callipers to hold the heat inside where is needed, rather then letting it go and degrade the brakes oil.

We can clearly see that the calliper without P-DEF need much more time to cool down at the same temperature of the brake with P-DEF, with the risk to arrive at the next braking still too hot and so already stressed.

Pressure and lengths of the breakings:

When we thought we unveiled every secret of this revolutionary element, another surprise caught us and, by their own admission, the EvoCorse engineers too.

Technology nowadays gives us the opportunity to record what is happening all around the car during every single competing centimetre of road. Due to the cost of this technology however, not every competitor can afford to have his car all wired up. Thanks to the professionalism of the “Lake Racing Team”, together with EvoCorse we also had the chance to monitor the brakes pressure behaviours for the first time using the P-Def.

Looking at the figures (Graph. 3) we notice a smoother and more regular use of the pedal, which also comes into action a fraction later on the “C” corer, as well as being released earlier.

Amazingly the P-Def has also allowed Basso to brake less and with a more regular use, giving also less pressure to the pedal. We do not know exactly in how many seconds this can be translated in pure stage/lap time, sure is a fact that with the P-Def, drivers who know how to slow down a car properly can also complete their test in a shorter time.

 Sure having lapped few times before has helped the driver using the brakes more efficiently, but there is also another fact we need to consider when explaining such impressive results.

Those 15-20° difference recorded on the brake pads (Ferodo DS3000 in this case) are the key, in a hotter environment they simply find themselves in the ideal working conditions, and they can reach it much earlier thanks to P-Def which also preserves them from unwanted cooling between corners.

If the benefits are very clear and unmistakable at our eyes after this test, there are also other considerations we feel like doing. EvoCorse has tried its new product on many different conditions, and if the most immediate results have come from asphalt runs, we also like to think about the possibility of using the P-Def on hot (or very cold) gravel events, specially with “left-foot breaking” drivers. When we thought about repeating the experience on a loose surface, they have confirmed they will receive the first impressions from a new test which will be soon carried out during the Argentinean round of the Wrc.

Our conclusions are that, such simple invention can make the difference and can help improving braking performances on many specific grounds or cars, by thermo-isolating the callipers and balancing the distribution of the heat. If it seems absolutely free from bugs, it must be said that in some cars, when installed in between brand new pads and discs, there may be the need of a little wearing off on this two parts, before the P-Def pads find their perfect positioning.

The correct use of P-Def for sorting specific situations out is of course left to the final users, whoever drivers or mechanics they may be, but EvoCorse is more then happy to offer advice or suggestions to this and all other products they make.