[bjohnsonsmith]

Originally Posted by Purist

F1, the WSC, and Can-Am all used the original Carousel (Turn 5). Among major series, only the USRRC used that old chicane, and even they dropped it in their final season (1968). From what I gather, Graham Hill crashed in that final couple of corners in 1969.

The IMSA double three-hour races were the effective reopening of Watkins Glen in 1984.

Track Layouts:
Original- 2.350 miles (1956-70)
Original w/ Carousel chicane- 2.300 miles
Grand Prix Circuit- 3.377 miles (1971-present)
GP Circuit w/ Esses chicane- 3.380 miles (1975-81)
GP Circuit w/ Inner Loop- 3.400 miles (1992-present)
Short Course- 2.427 miles (1971-present)
Short Course w/ Esses chicane- 2.430 miles (1975-81)
Short Course w/ Inner Loop- 2.450 miles (1992-present)

CART used the short course in 1979-80 and the GP circuit in 1981. The IRL/IndyCar used the GP circuit with the Inner Loop in 2005-10, and will do so again, presumably. ( I would be slightly amused if they found mid-corner and exit speeds in the Carousel to be somewhat lower if they actually didn't use the Inner Loop, and therefore drivers had to slow down for it, rather than using it as an acceleration zone for the run down to Turn 6.)

Thanks for the extra info, much appreciated,