(Adds investments to be made by consortium, background on project)
SAO PAULO, Jan 8 (Reuters) - A consortium formed by Brazilian private equity firm Patria Investments and Singapore's state investor, GIC, on Wednesday won an auction to operate for 30 years a highway in the Brazilian state of Sao Paulo after a bid of 1.1 billion reais ($270.42 million).
Patria, in which U.S. private equity firm Blackstone Group LP has a stake, competed with railway operator Ecorodovias Infraestrutura e Logistica SA for the Piracipacaba-Panorama roadway, which runs for 1,273 km (791 miles).
Shares of Ecorodovias, which offered to pay 527 million reais, were down 0.5% after the auction.
Patria and GIC must invest 14 billion reais in the roadway to improve its infrastructure and services, according to the concession rules.
Otavio Castello Branco, a partner at Patria, said in a statement that the fund manager intends to continue to invest in Brazilian roadways.
The so-called Pipa is the largest public road concession ever put up for auction in Brazil. ($1 = 4.0678 reais) (Reporting by Aluisio Alves in Sao Paulo Writing by Carolina Mandl Editing by Chizu Nomiyama and Matthew Lewis)