I had the same thoughts when I got my 2018 GT A10.
My 2012 A6 would roast the tires from a dead stop, but my 2018 stumbles when I hammer it.
The dude from Lund who tuned it says it goes into Transmission Protection Mode when floored from a dead stop, and the only way around it is to pull the...
That sounds very definitive..It would have to be very different.
I've logged sub 4 sec 0-60 times on my 2018 Mustang GT A10 with sticky tires and 3.15 gears.
I think a base C8 could match the Z51, without spending another 10k, i.e. with the right tires, but, no one knows for sure, yet.
Reminds me of the bulls&t 2018 Mustang GT advertising, "0-60 in under 4 seconds" which meant only with the A10 PP and those Michelin Pilot Sport Cup 2 tires. I'm pretty sure the base C8 can do those numbers without the Z51 package though,just need to ditch those all season Goodyears.