Seton's 302kph 'record' set to be broken.

Westpoint Racing driver Glenn Seton has said he expects his nine year 302kph record down Conrod Straight to be broken this weekend in the Australian V8 Supercar Series Super Cheap Auto 1000 at the legendary Mount Panorama race track.

The record of 302kph - about 188mph - was set in 1996, though there's a certainly amount of uncertainty about how valid a record the speed actually is.

"I'm actually not too sure how accurate that top speed is. The time was given to me by a television network at the time," explains Seton of the speed he's been credited with. "I didn't have access to the data, so I just took it to be true.

This year there's a change to the diff ratios for the V8 Supercars at Bathurst from 325 to a 315, meaning some are expecting a new fastest time down Conrod.

"Changing the diff ratio needed to be done," says Seton, who has come second the past two years at the landmark Australian race.

"Coming down Conrod the engine was on the rev limiter for about five seconds (on the old ratio), which is not good. The change ensures the protection of a piece of equipment that is worth over one hundred thousand dollars.

Seton is not too disappointed to be losing this long standing record. "Records are meant to be broken aren't they?" Seton said.

After Thursday's first and only V8 Supercar session, a two-hour practice, Seton and co-driver Dean Canto were tenth fastest.