This article will look at the newly released for 2018 Ferrari 488 GTE Evo and compare it to the previously used 488 GTE.









Ferrari 488 GTE Evo





From afar, these two look very similar, it is only up close you can see the main differences to the exterior of the two cars. To the left is the 2017 488 and the right is the 2018 onwards Evo variant.





The most noticeable difference to these two cars is the front splitter. This generates front downforce, to increase grip for cornering and braking from the high pressure produced on its top surface.

The proximity of a splitter to the ground influences the downforce produced; this is due to the contraction between the lower face and the ground accelerating the air and reducing its pressure. This combined with the high pressure above increases the total downforce produced. Past a certain point however, the downforce drops significantly.





Relationship between downforce, drag and proximity to the ground

488 GTE used in 2017

The central portion of the splitter for the 488 is raised to allow a larger quantity of air under the car through the diffuser at the rear of the car. The central portion is a compromise between the splitter and diffuser airflow.





2018 488 GTE Evo

The Evo spec 488 has a wider central portion with a more gradual/blended transition between high and low sections of the splitter. This should allow more airflow through the diffuser, which can provide a balanced front/rear downforce increase.





488 GTE used in 2017

The diffuser of the outgoing 488 consisted of a stepped design with a larger central portion corresponding with the raised splitter. There are also turning vanes behind the rear wheels to clean up the messy flow in their wake.





2018 spec 488 GTE Evo with vortex path highlighted

The 2018 Evo spec car has a larger diffuser to correspond with the wider raised section of the splitter. The central section has horizontal winglets to seal the low pressure from the higher pressure either side, these lower corners house the vortex produced by the pressure differential (vortex path highlighted in blue).

The intermediate channels are taller than previously, as it presumably is fed a higher flow rate of air. As this is taller, the exhaust is flattened to fit in a smaller gap.

The turning vanes are more aggressive behind the rear wheels, with a much higher angle.

These create their own vortices, which can help seal the outer edge of the diffuser from the higher pressure are around it, making sure it works as it should.

As these are now unsupported at the bottom, lets hope they can handle the contact sustained in tough endurance racing.





Lastly we'll take a look at the front bumpers, and the area ahead of the front wheels.

The 488 has always had sculpted bodywork in this area, with the car used in 2017 having nice curves.





Left: 2017 spec 488 GTE and Right: 2018 spec 488 GTE Evo





The Evo car has a larger undercut increasing the area available on top of the front splitter for high pressure area to act upon.

A downside to this undercut is that it introduces a higher angle directing flow outwards around the front wheel. This increases the out-wash around the wheel potentially increasing drag.

Aston Martin have gone in a different direction by running with a bumper that has a flat side in this area, shown below.





2018 Aston Martin Vantage GTE with much flatter sides to the bumper

We will have to wait and see if this area will be changed for the Le Mans rounds that require low drag rather than high downforce due to its long straight sections. I wonder if any teams will ever decide to go in a direction used by

road cars

and vent air to the lip of the wheel well to help straighten the air around the front wheel, like the image below. I know some road car manufacturers are looking at active/deform-able panels that look similar (but less aggressive)

to the Vantage GTE solution at speed, but return to their better looking sculpted form at low speed/when parked.





Bumper vent design to help straighten messy flow around front wheel



After the Paul Ricard Test we can compare the speed trap data and lap times between all the GTE competitors. Unfortunately the 2017 WEC Prologue was held at Monza, so we will have to wait for at least the first race to compare speed trap numbers between the 2017 and 2018 spec cars.



