Tickford Racing's Cam Waters has set the early Supercars pace on the streets of Townsville, pipping Jack Le Brocq for the fastest lap in practice.

Waters was the fastest driver in the opening session and backed it up with a 1:13.896 lap late in session two to claim Friday's fastest time.

It was a good introduction to north Queensland for Tickford's Ford Mustangs, with the 29-year-old's teammate Thomas Randle coming a respectable fourth.

"It was great to be quickest both sessions, so hopefully we can keep this momentum rolling," Waters said.

"We've been quite up-and-down this year and I guess trying to find out what works. We got it right at times, got it wrong at times, so when you do roll out it really sets up your weekend.

"Tom was super fast today as well. It's nice to have two cars that are competitive."

Le Brocq was the best of the Chevrolet Camaros and looked to have secured the fastest lap of the day, before Waters blitzed the field at the last minute.

"There's interesting places coming over the surface and the way the tyres react to it," said the Erebus Motorsports speedster.

"It's a bit weird coming from the heat (of Darwin) to this, the car moves around a bit more. It's going to be an interesting one tomorrow."

Mark Winterbottom, whose three Townsville race wins are the most of any driver competing this year, claimed the session's third quickest lap for Team 18.

Heavy kerb action tested the field, with Randle and Matt Stone Racing's Cameron Hill experiencing steering-rack issues in session one.

The weather also threw a spanner in the works, as teams held off changing their tyres in the drizzle, with a dry track expected on Saturday.

Triple Eight had a quieter day after Will Brown and Broc Feeney's one-two finish in Darwin. Feeney rounded out the top 10 in session two, with competition leader Brown coming in 12th.

Qualifying for race 13 of the season begins at 10.15am local time on Saturday, before a top-10 shootout to determine the final grid spots.

The first of two 250km races around Reid Park kicks off at 2.40pm on Saturday.