I was a little surprised the 2 cars Gonkulate so close since Mark has a much bigger cam, so I looked back at the Gonk. Right now Mark's Gonkulator file has that 3.08 gear and 1960's era street traction ie none.
By just adding a 3.55 gear and decent traction (making the 2 cars equal in those areas), and then shifting the big cam at 5600, the difference is now over 0.3 sec or about 3 carlengths. Equal race down low but then the big cam pulls away.
The 3.73 rear in Mark's car cut off almost another .10 sec so either gear would fix it.
Would still make a great timeslip race though, since things don't always turn out as Gonkulated!
