Cars are George Altomonte's business. Racehorses are his passion.

The prominent Sydney car dealer's Corumbene Stud in the Upper Hunter Valley has been the nursery for many horses who have given Altomonte some of his great highs in racing.

He began Corumbene in 1978 to foster his interest in thoroughbred after some years breeding stock horses.

On Saturday, the horse he rates at the top of the ones he has bred, Golden Slipper winner Overreach, who goes to Randwick on Saturday seven days after her big win to try to take the second leg of the two-year-old triple crown, the Sires' Produce Stakes.

Altomonte has no worries about the extra 200 metres and is already looking two weeks ahead to the Champagne Stakes over 1600 metres.

The Golden Slipper gave Altomonte the distinction of being the first individual to breed and race a Slipper winner since TJ Smith with Bounding Away in 1986.

He bred and raced Hasna, third in the Slipper and winner of the Sires' and the Champagne Stakes. He bred and sold the 2008 Slipper winner Sebring who also won the Sires'.

In Overreach Altomonte has the horse he believes can win all three.

"I have no worries about the distance of the Sires' or the Champagne Stakes," Altomonte said.

"Overreach pulled up so well from the Golden Slipper there was no hesitation about the back-up.

"If she wins on Saturday then she will definitely try for the triple crown."

Overreach is by dual hemisphere stallion Exceed And Excel out of Bahia, a mare dear to Altomonte's heart.

Injury ended her racing career prematurely after she registered four wins from four starts.

Just a few weeks ago, the mare was rushed to the Scone Equine Hospital with severe colic but she pulled through and so did her Redoute's Choice foal in utero.

On a day of short-priced favourites at Randwick, Overreach was at $1.55 on Thursday to win the Sires' with Guelph next best at $10.

Darley filly is the other runner by Exceed And Excel in the Sires' after her solid fourth in the Slipper.

Altomonte spreads his racehorses among several trainers with Gai Waterhouse the trainer of Overreach.

She also has Florid Affair in the Sires' for a syndicate which includes Gerry Harvey and the trainer's daughter Kate Waterhouse.

Florid Affair is the third elect at $11 and in the unlikely event she can beat her stablemate, there will still be a connection to Altomonte as she is by Sebring.