Matt Halliday will drive for the New Zealand A1 Grand Prix team in Round 3 of the World Cup of Motorsport in Portugal this weekend.

Halliday drove to a 3rd and 4th during Round 1 while Jonny Reid took the Black Beauty to two 4th placings in Round 2, leaving the team in second-equal spot on the championship table just one point behind Brazil.

A1 Team.NZL chief executive Bob McMurray says the team has confidence in both drivers and the choice was difficult.

"The clincher was the extra track time we have this weekend to break in the second car," McMurray said. "We have two forty-minute warm-up sessions before the two official one-hour practices tomorrow. That negates somewhat Jonny's knowledge of the circuit, which he gained driving Formula 3000 here last year.

"Jonny's also familiar with the Eastern Creek circuit where we're heading in a fortnight for the Australian round, so he's the most likely to drive there."

The Kiwi team has the opportunity to run its second car this weekend, but has decided to run the second engine with the chassis used in the first two rounds.

"We've groomed the chassis and it is a known quantity," McMurray said. "But it's worth breaking in the new engine and, with the extra warm-up session, we have plenty of time to ensure it is purring."

McMurray says set up will be all-important at the Estoril circuit, an ex-Formula 1 track just kilometres inland from the most western point of Europe.

"We're very close to the Atlantic Ocean and sand and wind can be an issue. The sand can make the track dirty and gritty, while the wind can affect gear ratios depending on how hard it blows."

Jonny Reid says there needs to be compromise in set-up given the 4.36km track has a heady mixture of tight corners and long sweeping turns, one of which catapults cars into the lengthy straight at speed.

"You rely heavily on traction from the car and it's a track that's good for slipstreaming on the long straight," Reid said.

"It's important to watch the gap between you and the car in front, especially coming out of the sweeping corner into the straight. If you're too close you lose the down force on the car and lose speed.

"You have to time the gap and have to be quite clever about getting to the straight well. The power boost button could be more relevant than previously."

Matt Halliday said learning a new circuit, as he did at Brand's Hatch in Round 1, was not an issue.

"You can do it in five seconds," Halliday said. "I just can't wait to get out there. Bring it on!"

Tomorrow will be a busy day for the team with four separate practice sessions. Saturday sees a final practice before the afternoon Qualifying Session determines grid positions for the first of Sunday's two races.