Sam Tordoff led the British Touring Car pack during free practice at Donington Park.
Aron Smith's BMR VW Passat set the pace in the first session, recording two times faster than Gordon Shedden's Honda Civic Tourer in second.
Smith then dipped under the 1m10s barrier with a 1m09.874s in the second session. That compares favourably with Shedden's 2013 pole time of 1m10.074s.
But Tordoff's Triple Eight MG6 then went even quicker, first recording a 1m09.794s, then leaving the benchmark at 1m09.684s in the final 10 minutes.
Smith's double BTCC champion team-mate Alain Menu failed to match the Irishman in either session, but ended up third quickest with 1m10.038s in FP2.
Jason Plato made it two MGs in the top four, while Adam Morgan's Mercedes improved in the final moments of FP2 to go fifth with 1m10.188s.
After being second fastest in FP1, Shedden only improved by 0.005s later and ended up sixth.
Championship leader Andrew Jordan, who will have to carry 45kg of success ballast in qualifying and race one, was seventh with 1m10.242s in his Eurotech Civic.
Colin Turkington was pleased with his WSR BMW in FP1. He didn't improve in FP2, but his morning effort of 1m10.258s was good enough for eighth quickest across the two sessions.
Former British F3 champion Marc Hynes showed much improvement over his Brands Hatch form to go ninth fastest.
Fabrizio Giovanardi and Matt Neal were next, meaning that all seven of the BTCC champions in the field were in the top 11.
A number of cars appeared to be marginal when it came to the new UK track limits, which could result in penalties when it comes to qualifying.
Several drivers were warned and the Audi A4s of Rob Austin and Hunter Abbott were black-flagged.
Follow the BTCC and WTCC races, Auto GP race two and the WEC season opener as they happen on Race Centre Live from 11:30am UK time on Sunday April 20
Practice 1 Pos Driver Car Time Gap Laps 1. Aron Smith BMR VW 1m10.041s 22 2. Gordon Shedden Honda 1m10.215s +0.174s 20 3. Colin Turkington WSR BMW 1m10.258s +0.217s 20 4. Matt Neal Honda 1m10.406s +0.365s 23 5. Marc Hynes MG 1m10.435s +0.394s 21 6. Jason Plato MG 1m10.453s +0.412s 18 7. Sam Tordoff MG 1m10.504s +0.463s 23 8. Jack Goff BMR Vauxhall 1m10.586s +0.545s 22 9. Alain Menu BMR VW 1m10.647s +0.606s 14 10. Adam Morgan Ciceley Mercedes 1m10.709s +0.668s 21 11. James Cole UA Toyota 1m10.801s +0.760s 19 12. Andrew Jordan Eurotech Honda 1m10.844s +0.803s 20 13. Rob Collard WSR BMW 1m10.912s +0.871s 19 14. Dave Newsham AmD Ford 1m11.227s +1.186s 23 15. Warren Scott BMR Vauxhall 1m11.243s +1.202s 18 16. Fabrizio Giovanardi Motorbase Ford 1m11.270s +1.229s 18 17. Tom Ingram Speedworks Toyota 1m11.288s +1.247s 17 18. Hunter Abbott RAR Audi 1m11.390s +1.349s 19 19. Nick Foster WSR BMW 1m11.453s +1.412s 21 20. Glynn Geddie UA Toyota 1m11.599s +1.558s 17 21. Martin Depper Eurotech Honda 1m11.661s +1.620s 24 22. Mat Jackson Motorbase Ford 1m11.751s +1.710s 16 23. Rob Austin RAR Audi 1m11.755s +1.714s 19 24. Robb Holland Rotek Audi 1m12.598s +2.557s 21 25. Chris Stockton BTC Chevrolet 1m12.930s +2.889s 18 26. Ollie Jackson Welch Proton 1m13.361s +3.320s 13 27. Simon Belcher Handy Toyota 1m13.402s +3.361s 13 28. Aiden Moffat Moffat Chevrolet 1m13.624s +3.583s 17 29. Jack Clarke Motorbase Ford 1m16.843s +6.802s 12 30. Lea Wood Houseman Toyota 1m21.183s +11.142s 2 Practice 2 Pos Driver Car Time Gap Lap 1. Sam Tordoff MG 1m09.684s 18 2. Aron Smith BMR VW 1m09.874s +0.190s 21 3. Alain Menu BMR VW 1m10.038s +0.354s 21 4. Jason Plato MG 1m10.094s +0.410s 18 5. Adam Morgan Ciceley Mercedes 1m10.188s +0.504s 25 6. Gordon Shedden Honda 1m10.210s +0.526s 22 7. Andrew Jordan Eurotech Honda 1m10.242s +0.558s 23 8. Marc Hynes MG 1m10.334s +0.650s 24 9. Fabrizio Giovanardi Motorbase Ford 1m10.368s +0.684s 21 10. Martin Depper Eurotech Honda 1m10.447s +0.763s 22 11. Tom Ingram Speedworks Toyota 1m10.478s +0.794s 24 12. Matt Neal Honda 1m10.506s +0.822s 21 13. Rob Collard WSR BMW 1m10.559s +0.875s 22 14. Jack Goff BMR Vauxhall 1m10.742s +1.058s 23 15. Mat Jackson Motorbase Ford 1m10.753s +1.069s 19 16. Colin Turkington WSR BMW 1m10.774s +1.090s 21 17. Dave Newsham AmD Ford 1m10.787s +1.103s 18 18. Rob Austin RAR Audi 1m10.915s +1.231s 22 19. Warren Scott BMR Vauxhall 1m10.928s +1.244s 17 20. Nick Foster WSR BMW 1m11.067s +1.383s 21 21. Glynn Geddie UA Toyota 1m11.128s +1.444s 20 22. James Cole UA Toyota 1m11.162s +1.478s 17 23. Hunter Abbott RAR Audi 1m11.432s +1.748s 18 24. Robb Holland Rotek Audi 1m11.480s +1.796s 21 25. Chris Stockton BTC Chevrolet 1m11.825s +2.141s 22 26. Lea Wood Houseman Toyota 1m11.829s +2.145s 19 27. Simon Belcher Handy Toyota 1m11.948s +2.264s 21 28. Aiden Moffat Moffat Chevrolet 1m12.245s +2.561s 18 29. Ollie Jackson Welch Proton 1m12.509s +2.825s 13 30. Jack Clarke Motorbase Ford 1m13.283s +3.599s 15 31. Dan Welch Welch Proton no time set 3