It was a rapid final hour-long hit-out at Mount Panorama with times dropping into the 2m02s almost immediately.
The first came from former race winner Matt Campbell, the hometown hero putting the Manthey EMA Porsche on top with a 2m02.774s.
That was still the benchmark when the session was red flagged 15 minutes in thanks to Shane Woodman crashing the #66 Sin at the Esses.
Once the session went green again Engel went on a charge in the #999 GruppeM Mercedes, going second fastest with a 2m02.960s.
He then moved into top spot with a 2m02.618s.
With five minutes to go Chaz Mostert made his move in the #65 Melbourne Performance Centre Audi, dropping a wheel at the last corner as he fell four-hundredths short of Engel's time.
It wasn't until the very end of the session that Engel was relegated to second, Stolz putting the #75 SunEnergy1 Racing Mercedes on top with a 2m02.433s.
The #999 and #65 entries remained in second and third place respectively, while the #912 Porsche ended up fourth based on Campbell's early time.
The Triple Eight Mercedes were fifth and sixth, Shane van Gisbergen leading Supercars enduro partner Richie Stanaway, ahead of Chris Mies in the #777 MPC Audi.
Tony D'Alberto put in another impressive performance in the #6 Wall Racing Lamborghini to end up eighth fastest and best of the Silver entries, ahead of #74 MPC Audi and the #77 Craft-Bamboo Mercedes.
Qualifying starts at 12:45pm local time.
Watch it live and free on Motorsport.tv (not available for viewers in Australia and New Zealand).
