Kobayashi posted a 2m00.747s aboard the #7 Toyota GR010 HYBRID to beat team-mate Kazuki Nakajima, who ended up half a second behind on 2m01.266s in the second of the Japanese marque’s new Le Mans Hypercars.
Filipe Albuquerque again set the pace in LMP2 for the United Autosports team to claim third overall at the end of the 10-minute session in which only one driver takes the wheel under the WEC’s new qualifying format.
The Portuguese posted a 2m02.937s on his first flying lap aboard the United ORECA-Gibson 07, but unlike the Toyota drivers he went for a second run on new set of tyres and improved to 2m02.404s.
Kobayashi said: “We really tried to do the maximum with the car, pushing with low fuel.
“I felt the car was pretty good: we’d changed set-up from free practice 3.”
The Alpine-Gibson A480 LMP1, the final car competing in the Hypercar class, managed one flying lap right at the end of the session.
Nicolas Lapierre’s 2m02.652s was enough to put him ahead of all but one of the LMP2s in fourth place.
Nyck de Vries claimed fifth position and second in LMP2 in the fastest of G-Drive Racing’s Aurus-badged ORECAs.
His late 2m02.984s left him half a second behind Albuquerque but was enough to bump Giedo van der Garde in the Racing Team Nederland ORECA down to sixth.
#92 Porsche GT Team Porsche 911 RSR – 19: Kevin Estre, Neel Jani
Photo by: JEP / Motorsport Images
Kevin Estre took pole in GTE Pro for Porsche by over a second with what he described as a “perfect” lap.
The Frenchman set a best lap of 2m11.219s in the Porsche 911 RSR he shares with Neel Jani.
That compared with the 2m12.351 from Miguel Molina, which put the best of the AF Corse Ferrari 488 GTE Evos second.
Molina just edged out Richard Lietz, who ended up on a 2m12.379s in the second of the Porsches.
Alessandro Pier Guidi was a further tenth back in the other Ferrari, while Antonio Garcia was nearly two seconds off the pace in the solo Chevrolet Corvette C8.R.
TF Sport Aston Martin driver Ben Keating topped the times in GTE Am with a 2m14.660s lap completed after the chequered flag had fallen.
Keating’s time in the replacement Aston Martin Vantage GTE, bought in to replace the car which he destroyed in the pre-event Prologue test, was enough to bump fellow Aston driver Paul Dalla Lana off the pole.
The GTE session was red-flagged twice after near-identical incidents involving Am class Porsches.
Dempsey-Proton team boss Christian Ried crashed heavily at the top of Eau Rouge at the start of his first flying lap and then Egidio Perfetti crashed on his outlap on the resumption of the session.
The WEC Spa 6 Hours starts on Saturday May 1 at 12.30pm BST and will be streamed live on Motorsport.tv.