IndyCar has announced a raft of rule changes including alterations to aero packages and pit lane speed limits for the 2016 season.

Series officials have confirmed the aero specifications for each of the five ovals the championship will visit next season.

Cars will run to the same specification aero package used in 2015 at the Indianapolis Motor Speedway albeit with the addition of rear wheel guard infills that were implemented at Texas Motor Speedway, as well as a domed skid plate underneath the car and rear wing beam flaps.

The skid plate and beam flaps were announced last month as part of IndyCar’s safety enhancements which will be used again at Texas Motor Speedway next year.

Phoenix International Raceway, which joins the schedule next year, will run the same aero configuration used at the Iowa Speedway this year.

Meanwhile, Iowa Speedway will see a slight decrease in available downforce due to a reduction in rear wing angle.

From 2016 the pit-lane speed limit has been reduced to 50mph (80km/h) on all ovals. Superspeedways had previously operated to a 60mph (96km/h) limit.

IndyCar has also made changes to the Indianapolis 500 qualifying and rookie orientation test program.

The provisional field of 33 cars for the 100th running of the Indy 500 will be set on the first day of qualifying May 21 with the traditional bumping of cars due to take place at the end of the session.

The grid will then be finalised on the second day of qualifying which will then see championship points allocated.

Double points will be on offer for the Indy 500 and the season finale at Sonoma.

Next season will see the three phases of the rookie orientation test tweaked.

The Rookie Orientation phases for 2016 are 10 laps at 210-215mph (337km/h-346 km/h), followed by 15 laps at 215-220mph (346km/h-354km/h) and 15 laps at 220-plus mph.

Each phase sees an increase of 5mph (8km/h) from 2015.

Minimum car weights have also been amended with the new rules stipulating an increase to 1,610 pounds (730kg) for road and street courses and 1,580 pounds (716kg) on ovals.