WEC 2018 season is moving forward providing clear figures about Toyota TS050 supremacy on LMP1 class. No discussion about flying lap capability, reliability and race pace consistency so far, nevertheless last race at Silverstone has offered an unpredictable results.
Toyota TS050 Hybrid n. 8 , the winning car driven by Fernando Alonso, Sébastien Buemi and Kazuki Nakajima, as well as sister car .7 were found to be in non-conformity of Article 3.5.6.d of 2018 LMP1-H Technical regulation that cover permitted deflection of the skid block.
Rebellion R13 n.3 take victory after Toyota exclusions following post-race scrutineering (with Steward’s decision n. 25 and 26).
Nowadays almost all race cars have a skid block mounted below the so called “reference plane” underneath the car. Reason for adopting the skid block is the simple aim of technical regulations to limit tendency to run the car at minimum ground clearance.
Small ground clearance maximizes ground effect and aero performances but causes bottoming and ground contacts with kerbs and asphalt with consequent wear of skid block. A trade-off need to be set.
LMP1 H technical rules specify a permitted wear of 5mm maximum (thickness is measure before the race and after practice sessions and race end). As seen from the picture skid block extend between front and rear axle centreline and could be made by a maximum of 4 parts. Fasteners used to attach the skid to reference surface have specified size in order to prevent misuse of these points to mitigate the wear.
Toyota TS050 - Skid block mounted underneath reference surface of the floor
Front part of the skid block may deflect vertically no more than 5mm whit a load of 2500 N applied upward in any point of the wear surface using a ram with 50mm contact surface.
The maximum permitted deflection is 15mm when an upward load, capable of lifting the front when from ground, is applied.
Toyota TS050 – details of deflection test on front part of the skid block
These requirements have not been satisfied by both car n.7 and 8 during scrutineering causing their exclusion from the race.
Small details may have huge impact on results this is very true in motorsport.