It has not been a long winter for Formula 1 fans. Truncated by a stateside cameo for F1’s resident Jack-of-all-trades, frenetic racing in Formula E and a handy reminder of David Coulthard’s skills in the Race of Champions; F1 fans have not been short of things to talk about over the bleak winter months.

Whatever winter vacuum there was would soon abate as the pleasantly familiar cycle of anticipation and debate heralded the launch of F1’s 2018 challengers. However despite the F1’s community’s ravenous appetite, there were limits to how informative a collection of predominantly rendered images could be. Talk would soon turn to how the 2018 cars would fair in their debut outings at the first Barcelona test.

A Renault-powered McLaren, ominous murmurs from Brixworth, a youthful driver line-up at Williams, more aggressive tyres and the ever divisive halo: 2018 promises one of the most intriguing pre-seasons for many years. This is Read Motorsport‘s essential spotter’s guide for what to look out for when the cars hit the track for the first test: