Great Britain's women twice broke the world record as they won the new-look team pursuit at the Track Cycling World Cup in Manchester.
Laura Trott, Dani King, Joanna Rowsell and Elinor Barker lowered their own record in qualifying, then went faster again as they beat Canada in the final.
Britain's men's team pursuit also won, beating arch-rivals Australia.
The women's sprint team took silver behind Olympic champions Germany, while the GB men's sprint trio took bronze.
They beat New Zealand to third place as Germany defeated Russia for gold.
Katie Archibald, omitted from the GB squad but riding for Scotland's Braveheart trade team, came second in the non-Olympic women's scratch race behind Poland's Malgorzata Wojtyra.
The team pursuit provided the home crowd's highlights on a Manchester track known for its speed, as Britain's women eventually finished the day with a new best time of four minutes 19.604 seconds.
The women's event has this season been extended to four riders and four kilometres - up from three riders and three kilometres - to match the men's event.
Britain won the European title under the new rules last month, in what was also a world record at the time.
Their continued progress in Manchester shows they have adapted more swiftly than any other nation to the four-woman event - though Trott, King and Rowsell were equally prolific as world record-setters in the three-woman version, which they won at London 2012.
Rowsell, 24, told BBC Sport: "Over the next three years you'll see that record get lower and lower.
"We all live and die for the team pursuit. It's great to be back here, racing for a home crowd, and it's exciting to go out and break world records again.
"A few of the top nations weren't here so we're not getting complacent. The rest of the world is really going to grow into this event over the next few years."
Canada, themselves a class above the remaining nations in qualifying, finished more than eight seconds behind the British quartet in the final.
The GB women's time would have won the men's event at any Olympic Games up to Moscow 1980, where the Soviet Union posted 4:15.70.
Trott said: "It feels amazing. We kind of knew the world record was going to go, but we didn't think it would go by that much. It really came together in the final."
Team pursuit European champions Ed Clancy, Andy Tennant, Steven Burke and Owain Doull won the men's final in a time of 3:58.654 to Australia's 3:59.293, a margin of 0.639 seconds in a rivalry which has spanned the past decade.
The GB endurance squad is missing Olympic champions Geraint Thomas and Peter Kennaugh, who have returned to road racing after London 2012.
"We keep saying this is a developing team," Clancy told BBC Sport.
"But when you think back to 2008, when we had the World Championships here [in which a GB team featuring Thomas and Bradley Wiggins won world gold, then the Olympic title], we're not a million miles off that now - with a so-called development team."
Tennant added: "It's been a good start to the track season and hopefully we can carry this run on to Mexico [the next World Cup, in December] and Colombia."
Cali, in Colombia, will host the 2014 World Championships in February. This World Cup forms an important chance to impress national selectors with Cali in mind.
Becky James and Vicky Williamson felt they did that; both riders set personal bests as they took team sprint silver behind Olympic and world champions Miriam Welte and Kristina Vogel of Germany.
"I didn't expect the time I came away with today at all. I'm really happy," said James, who won two world titles in Belarus earlier this year, where GB finished third in this event.
"I've got two more full days of racing so it's a big weekend of racing for me."
In the last event of the night, Jason Kenny, Matt Crampton and Philip Hindes raced to bronze in the men's team sprint, Crampton having replaced Kian Emadi after qualifying.
Saturday features James and fellow world champion Kenny in the women's sprint and men's keirin respectively, and Trott takes part in the first three events of the women's omnium.
The men's omnium also concludes on Saturday, while Australia's Anna Meares, the Olympic sprint champion, is set to race in her first major event since the Games.
Sunday's action includes the men's sprint and women's keirin.