As we've previously reported, the Detroit Belle Isle Grand Prix has one of the longest construction timelines for any street race in the world. We verified that by checking the construction period for all other IndyCar and Formula One races worldwide.
Penske's team used to spend nearly four months on the project, but it claims the race's set up and break down is now completed in 68 days. Compare that to other city's races: Toronto, 21 days; St. Petersburg, Florida, three to four weeks; or Monaco, 49 days. Long Beach has a similar timeline, while Singapore is much longer.
That's unless one factors in the extra weeks Penske's team spends remediating the damage it does to Belle Isle (other races factor remediation into their construction figures). Then the timeline for the June 1 to June 3 event extends much longer.
Yet Grand Prix manager Michael Montri told the Detroit News that Penske's team is setting up and breaking down each mile of track faster than most other races. That includes the Toronto Honda Indy, which indisputably has a construction period that's about 47 days shorter than that in Detroit.
Where did Penske's team get its numbers? We asked and found that some of Montri's figures simply aren't accurate. But the rest of it is truly an exciting exercise in inventive accounting. As Mark Twain once said, "Figures don't lie, but liars figure."
Regardless, this discussion is especially important right now. The contract that allows the Grand Prix to use the park ends this year, and the construction, traffic jams, island closures, and use of the park have led to protests, organized opposition, and articles questioning the race.
The construction is a source of conflict between the park-going public and billionaire race organizer Roger Penske because people go to the park to relax, not to visit a construction zone.
So, as it negotiates a new contract, Penske's team needs to create the appearance that its construction timeline isn't longer than that of other races. But it is. Follow along as we get down in the weeds.
One good measure of efficiency in setting up a course is to look at how many days it takes to set up one mile of track. The Grand Prix's track is 2.3 miles, and it takes 68 days to set up. 68 days/2.3 miles = 29.5 days per mile.
In Toronto, the 1.8-mile course is up and down in about 21 days. 21 days/1.8 miles = 11.6 days per mile. (And all its construction is done at night with no road closures.)
In St. Petersburg, reports put construction between 18 days and around four weeks. Its course is 1.8 miles. 28 days/1.8 miles = 15.5 days to set up one mile of track, on the high end.
So the Grand Prix's construction takes a lot longer those races no matter how you slice and dice the numbers. But Montri claimed to the Detroit News that the Grand Prix's set up takes 13.8 days per mile. That seemed off, so we asked Grand Prix spokesman Merrill Cain about the math.
His response shows how far Penske's team is willing to go to push the numbers in its favor — Cain tells us that roads have two sides, so one has to double the length of the course when calculating the days per mile.
While that might seem absurd, there's a rationale that makes sense for Penske. The Grand Prix's course is longer than others around the world, so the new formula pushes its days per mile count down. But Montri still got some numbers wrong. For example, with the course length doubled, Detroit takes 14.7 days to set up a mile of track, not 13.8, as Montri claimed.
Simple math also shows that with course lengths doubled, it takes Toronto 5.5 days, St. Petersburg 7.7 days, and Monaco 12.25 days to set up a mile of track. All those tallies are lower than what Montri claimed in his comments to The News.
Cain didn't have an explanation for the inaccurate numbers and the incorrect math.
We also mentioned the inaccuracies to The News, but received no reply.
Montri also ignores that races like Monaco, Toronto, and St. Petersburg are put together and disassembled in environments that are far more complex than that of isolated Belle Isle.
It's also worth noting that this isn't the first time in 2018 that Penske's team is fudging the numbers. Several sports economists point out that Penske's claim that the race has a $58 million economic impact is false, and the true figure is more in the $10 million range, if that. Find our story on that issue here.

Photo by Tom Perkins
Scott Memorial Fountain pictured from Sunset Drive in April 2017. Four rows of fencing separate the river and fountain.
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