James Walker dominated Friday's pair of free practice sessions at Silverstone ahead of round five of the Formula Renault 3.5 Series.
The Jersey driver was one second faster than Carlin's Oliver Turvey in this morning's one hour session, before finding half a second in the afternoon to record a lap of 1m34.003s.
"I am very pleased with that," said P1 Motorsport driver Walker. "We were very quick on old tyres this morning, I was surprised by the margin but we managed to get a lap in before the rain came and I think that may have caught a few people out.
"In the afternoon we were P1 within three laps, having sat out the first 10 to 15 minutes. We used a new set of tyres at the end, and on my last lap I was 0.3s up on best time when I caught [Marco] Barba and someone else going slowly at Priory.
"I was hoping that they would get out of the way, but I didn't quite make it through. It's great to dominate today, but I am sure that everyone will up their game tomorrow."
Championship leader Marcos Martinez (Pons) narrowed the bridge to Walker in the second session to finish 0.3 seconds adrift. Martinez is set to test a 2008 Renault R28 Formula 1 car tomorrow afternoon, his reward for leading the championship at the halfway point.
Tied with Martinez on 56 points at the head of the championship, Bertrand Baguette (Draco) demonstrated that he should again be a contender by ending the morning in third. That position was occupied by Tech 1 racer Brendon Hartley in the second collective test.
Comtec's newcomer Jon Lancaster rounded out the top six in the morning, but was beset with steering problems shortly after fitting new tyres.
"I had to use more lock for the right-handers than for the left, and it gave an impression of understeer," he said.
Spaniard Miguel Molina recovered from a clutch problem that restricted his running to eight laps in the morning to finish sixth fastest in the second, hour lour long session.
In the sister Ultimate-Motorsport machine, Greg Mansell made it four British drivers in the top ten in the morning and was 12th on combined times.
Pos Driver Team Time Gap
1. James Walker P1 1m34.003s
2. Marcos Martinez Pons 1m34.344s + 0.341s
3. Brendon Hartley Tech 1 1m34.602s + 0.599s
4. Adrian Zaugg Interwetten 1m34.668s + 0.665s
5. Bertrand Baguette Draco 1m34.718s + 0.715s
6. Miguel Molina Ultimate 1m34.814s + 0.811s
7. Jaime Alguersuari Carlin 1m34.867s + 0.864s
8. Charles Pic Tech 1 1m34.931s + 0.928s
9. Marco Barba Draco 1m34.944s + 0.941s
10. Jon Lancaster Comtec 1m34.973s + 0.970s
11. Chris van der Drift Epsilon Euskadi 1m35.326s + 1.323s
12. Greg Mansell Ultimate 1m35.342s + 1.339s
13. Daniil Move P1 1m35.459s + 1.456s
14. Oliver Turvey Carlin 1m35.492s + 1.489s
15. John Martin Comtec 1m35.529s + 1.526s
16. Pasquale di Sabatino RC 1m35.602s + 1.599s
17. Adrian Valles Epsilon Euskadi 1m35.779s + 1.776s
18. Fairuz Fauzy Fortec 1m35.954s + 1.951s
19. Michael Herck Interwetten 1m36.024s + 2.251s
20. Federico Leo Pons 1m36.359s + 2.356s
21. Sten Pentus Fortec 1m36.370s + 2.367s
22. Anton Nebylitskiy SG 1m36.748s + 2.745s
23. Guillaume Moreau SG 1m36.874s + 2.871s
24. Filip Salaquarda Prema 1m36.906s + 2.903s
25. Julian Leal Prema 1m37.150s + 3.147s