The Sydney Motorsport Park test marked the first time all 25 of the brand new Gen3 cars shared the same circuit at the same time.
Supercars used that opportunity to monitor and collate data that will now be used to finalise the sporting and technical rules.
That included weighing all of the cars as it looks to settle on a final minimum weight for the 2023 season.
It's expected the heavier of the cars will be used as the minimum, although even then the number is expected to be lower than the Gen2 cars that were used until the end of last season.
As for refuelling, parameters such as CPS windows and fuel drop for the longer-distance races are also yet to be set.
In that respect yesterday's test was critical given it was the first time the cars had run on the new E75 fuel blend.
One thing that is expected is that stop times will be longer with these new cars thanks to the new refuelling system.
The single-probe system, which replaces a dual-probe system, is narrower in diameter and will therefore fill slower than its predecessor.
There are suggestions that filling a car from empty with the fuel rig takes as much as a minute, with stop times in a typical refuelling race set to be around 15 seconds longer than before.
That could feasibly be mitigated by lowering the required fuel drop, although a number of teams canvassed by Motorsport.com on the matter weren't concerned about longer stops.
"We've got to understand exactly what the fuel times are and if there's anything that can be done," said Triple Eight team manager Mark Dutton.
"The new system is amazing; it's safer and better. We haven't done fuel time drops on ours, we'll do that at the end of this week or start of next. We'll feed that information back to Supercars and then look at if we do need to tune up the minimum drop.
"Even that isn't that easy to do. All of the fuel towers are calibrated for the bigger drops, and that's a process that takes two days, with two people. It's not so easy to do.
"But if it needs to be done, we'll do it."
Erebus CEO Barry Ryan added: "As long as it's the same for everyone, it doesn't really matter. You'll get in and out of pitlane as quick as you can, try not to go a lap down, and drop yourself where you've got clear air.
"It's all the normal stuff, just with a bit more pitlane transition time."
Other rules still be finalised include the homologation of both the Ford Mustang and Chevrolet Camaro.
That's been complicated by the ongoing concerns over parity regarding both aero and engines.
It's understood mapping changes were made to both engines on the eve of the SMP test, with sources revealing that the Chevrolet engine was given a longer shift cut.
The aero parity will go under the microscope next week when Supercars holds a re-run of its VCAT homologation process.