Building on its most successful season, the Toyota TR 86 Series has confirmed six new cars are under construction for the coming 2016-2017 championship and has announced a series of test days for intending racers.

The championship is now heading into its fourth season, with all dates and all but two circuits confirmed.

Toyota Racing New Zealand TR 86 category manager Geoff Short says interest in the coming championship is already higher than it was in mid-2015. A total of 26 drivers raced the most recent season, most of them contesting all six rounds and some taking the opportunity to test their speed and skill in one or two rounds. Grids for 2016-2017 are likely to run to 20 or more, with the championship capped at 24 cars for any round.

"Toyota New Zealand has approved a build programme for six new cars in response to strong demand for cars throughout last season and in the months since. We have a good number of recent racers returning and there is interest from throughout this country and also from Australia, so we are looking forward to another epic season of top level competition," he said.

All the TR 86 race cars eligible to compete are built in Auckland by Toyota Racing New Zealand.

"This ensures that the racing is close and exciting at every round. I am very confident that we will have a full 24 car grid for this season's championship. It's going to be an exciting season with the calibre of drivers that are looking to compete."

Australia has this year established its own race series for the 86 and has secured grids of up to 38 cars which compete at V8 Supercar rounds. As part of his prize for winning the 2015-2016 New Zealand series, champion Ash Blewett will race at the annual Bathurst V8 Supercar race weekend in an Australian-specification car.

Intending drivers and race fans can get a closer look at the TR 86 when it goes on show at the annual CRC Speed Show 16/17 July where Mr Short expects to make some 'exciting' announcements.

"Seats for the coming championship are already in short supply. Following the Speed Show we will be holding four testing opportunities at Manfeild, Ruapuna, Hampton Downs and Taupo for any prospective competitors looking to fill the few drives," he said.

The TR 86 series has been confirmed as the top single-make category to join the annual V8 Supercar race event at Pukekohe in November. The championship will be fought out over a further five rounds and at three of these events will share top billing with New Zealand's leading single-seater championship, the Toyota Racing Series. The final round is at Hampton Downs, halfway between Hamilton and Auckland, in March 2017.

"Racing was close and exciting when we joined the V8s at Pukekohe last year and we expect the action will be spectacular this time around. Pukekohe is one of the fastest places our championship races. From there we head to Taupo and then into the South Island, making the TR 86 Championship a truly national series."