Wall topped the first session on Friday morning before a well-timed new-tyre run saw him bump Andre Heimgartner from the top spot late in the second session; his flying 2m08.711s lap the fastest Carrera Cup time of the day.
Heimgartner and Lars Kern completed the top three ahead of a typically competitive Carrera Cup pack.
Despite the temperatures soaring by the time the cars hit the track for the second session late in the day, lap times improved as teams came to grips with the circuit with a majority of competitors banking their quickest times in the second session.
Just 1.6 seconds covered the 10 fastest cars despite varying strategies – some electing to run new tyres and some not.
Wall, who has bountiful experience at Sepang racing in the circuit’s annual 12-hour endurance race, said he was focusing on making sure his car was in good shape for qualifying tomorrow.
“I haven’t been here in a long time so we were fortunate enough to find a pretty good setup quite quickly in the first practice,” said Wall. “I’m happy with where we are at. We’ll just make a few little tweaks in the car now for tomorrow.
“It’s mega to be back here in Malaysia. It has been seven years since I last raced here and this time around I’ve got a few more grey hairs and three kids. We’re having an incredible time and I think everyone is enjoying it as much as I am, for sure.”
Lars Kern was third overall in his Porsche Centre Melbourne entry, making his return to the championship after contesting the opening two rounds earlier this year.
Nick McBride and Cameron McConville completed the top five, with Dylan O’Keeffe, Jaxon Evans, Alex Davison, Michael Almond and James Abela completing the top-10.
Meanwhile, Miles was only 0.09s faster than Stephen Grove in the TAG Heuer Carrera Challenge times, with Dean Cook an impressive third.
The McElrea Racing driver edged Grove in both sessions today, however said he was anticipating a close fight amongst the Challenge class runners this weekend.
“It’s so cool to be at a circuit like this. Sepang really suits our cars; it’s flat and really open and is a lot of fun in a GT3 Cup car. I’m a bit surprised to be setting the pace in the Challenge class because a couple of guys in the class have been here before,” said Miles.
“This is a really special experience. I’m really looking forward to the combined race with all the Challenge drivers and Pro-Am drivers from Carrera Cup Asia, that will be a lot of fun, but to come to a facility like this that is set up for Formula 1 and really suits our cars is just incredible.”
Porsche Carrera Cup Australia cars will hit the track tomorrow morning, Malaysian time, for qualifying prior to the first of two 13-lap races that make up round five of the 2017 championship.
Porsche Carrera Cup Asia & Australia will then combine for a pair of races on Sunday afternoon.
HOW TO WATCH: Broadcast/Live Stream Schedule
All qualifying and race sessions, including the two joint races, will be available to view via Facebook Live on the championship’s page and also streamed live via the http://www.carreracup.com.au and http://www.speedcafe.com websites.
Stream sessions (AEST)
Qualifying – 12:35pm (AEST), Saturday July 22, 2017
Race 1 – 7:00pm (AEST), Saturday July 22, 2017
Race 2 – 12:55pm (AEST), Sunday July 23, 2017
Invitational Race, Overall – 4:25pm (AEST), Sunday July 23, 2017
Invitational Race, Challenge/Pro-Am – 5:20pm (AEST), Sunday July 23, 2017
Saturday July 22, 2017
10:35am Qualifying (30 minutes)
5:00pm Race 1 (13 laps)
Sunday July 23, 2017
10:55am Race 2 (13 laps)
2:25pm Invitational Race, Overall (13 laps)
3:20pm Invitational Race, Challenge/Pro-Am (13 laps)