Scrapping "bells and whistles" on a mega rail loop has not killed off the project as a state election issue but several experts are backing cost-cutting moves.
Victorian Premier Ben Carroll on Tuesday took a scalpel to Suburban Rail Loop East, a long-time Labor state government pet project, before the November election.
The Suburban Rail Loop is a planned 90km orbital line stretching from Cheltenham in Melbourne's southeast to Werribee in the outerwest via the airport at Tullamarine.
The 26km eastern section from Cheltenham to Box Hill was slated to cost between $30 billion and $34.5 billion, with a target delivery of 2035.
Mr Carroll has vowed to find $2 billion in savings, including an immediate $1 billion by cutting the project's scope.
Under the changes, underground station interchanges at Box Hill and Glen Waverley will no longer be built, with a plan to instead provide surface transfers.
Other moves include finding alternative ways to deliver sufficient parking in Glen Waverley, scrapping a second station entrance at Clayton and axing complex pedestrian bridges in Burwood and Cheltenham.
A community projects fund will be wound up, some future precinct works scaled back and the Suburban Rail Loop Authority folded into the Victorian Infrastructure Delivery Authority.
The commonsense changes removed project "bells and whistles", Mr Carroll said.
"Overpasses, walkways, car parks, community grants are nice to haves but they are not needed to build the orbital railway line," he told reporters.
Public Transport Users Association spokesman Daniel Bowen said the changes risked the project not realising its potential.
"Ensuring a rail line is easy to use and that the interchange is efficient and quick to existing lines is not 'nice to haves' - that's essential," he told AAP.
Each of the features would have benefits to users and local residents but the value for money they provided should also be re-evaluated, Monash University transport expert Graham Currie said.
"It is always possible that these projects could be revisited in future years when the fiscal situation is more favourable," Dr Currie said, adding the loop remained a "visionary project".
The changes will not slow works, with tunnel boring machines to enter the ground on schedule.
Mr Carroll, who replaced Jacinta Allan as premier in late July, has also vowed to establish an independent technical review to target another $1 billion in savings.
A panel of tunnelling and engineering experts will oversee the review and report back in three to six months.
No more contracts will be signed until the review is complete.
After the review, the revised estimated spend for SRL East could fall to $32.3 billion.
With Victoria forecast to tally almost $200 billion in net debt by 2030, former Labor senator Stephen Conroy urged Mr Carroll to cut further.
"This is a dog of a project," Mr Conroy told News24 TV.
David Hayward, a public policy expert at RMIT University, said project amenity restrictions may be unwise but it was politically shrewd by Mr Carroll.
"The Labor government has been in quite a bit of trouble over the last couple of years over claims of spending too much, borrowing too much," he said.
Dr Hayward said proceeding was a "no-brainer" given the federal Labor government had committed $6 billion and the $1.8 billion estimated cost of ripping up more than $13 billion in signed contracts.
The Victorian coalition has vowed to pause and review SRL East if it wins the election.
Opposition public transport spokesman Matthew Guy said Victorians deserved to clap eyes on all related contracts before the election.
"You ask me how long is it (the review) going to take? My answer to you is show me the contracts, I'll give you an answer straight away," he said.
Australian Associated Press