The Chevrolet map only made it through the first practice session, however, with drivers reporting issues with idle, downshift blip and drivability.
Supercars elected to ditch the map between the two practice sessions, the Camaros all reverting to the same map used last time out in Tasmania for the remainder of the Darwin weekend.
The new map did undergo some real world testing, having been run by the likes of Triple Eight and Brad Jones Racing between the Tasmania and Darwin events.
However series leader Erebus, which lobbied to have the Darwin map dumped after practice 1 yesterday, feels it was the wrong decision to roll it out during a race meeting.
That's something the in-form team will push back against in the future.
"It was a tough Friday, losing a complete practice session," said Erebus CEO Barry Ryan.
"The GM engine map supplied by the homologation team ruined our first practice session, rendering the whole session useless.
"It’s frustrating, but it sounds like they team made some gains towards the end of practice 1 when #88 went fastest. Hopefully it’s a gain for the future.
"It’s a shame all of the GM teams were guinea pigs for the engine map as we believed it was already tested and proven.
"We have not had any problems with our engines all year so we will be resisting changes again until we get to test them outside of a race meeting.
"On the positive side we bounced back strong in practice 2 once the engine map was back to what we know, with Brodie [Kostecki] fourth and the first of the GM cars. Will [Brown] made an error on his new tyre run but both cars seem to be behaving well."
The roll-out of the new Ford map was less troublesome, with Mustang-shod drivers locking out the top three on combined practice times.
Dick Johnson Racing's Anton De Pasquale led the way on Friday ahead of Tickford pair James Courtney and Cam Waters.
The true form of each brand will become clearer following qualifying this morning, which kicks off at 11:30am local time.
