It should be a Hi-Po V-8 (273 4bbl) to start, I would think. I'm kind of curious to know myself. Someone here will know what to look for right away, to tell if it's a REAL Formula S car.
I'm literally trying to search for answers as we speak.
Some literature says what you said.....it'll have the 273 Commando, 4 barrell.....upgraded suspension.....sway bar....but surely any car could have ticked those boxes - or maybe not ???