"We think it is ridiculous that in New Zealand's capital city, in the 21st century, we are still using a two lane tunnel built in 1931."
But Transport Minister Phil Twyford said renegotiating the project would set it back years.
"This is coming from a political party who had nine years in Government. Their only transport achievement in Wellington was to fail in forcibly trying to impose a giant concrete flyover on the Basin Reserve."
National has all but promised to bring forward construction of the second Mt Victoria tunnel in the project's sequencing.
During his speech Bishop pointed to widespread support for projects like trenching Karo Drive, afterwards he said an "ideological aversion" to trenching or adding tunnels was where the Government had fallen short on the package.
He also confirmed the funding split between local councils and the Government would be up for negotiation.
Currently central Government is footing 60 per cent of the bill leaving local councils to pick up the rest.
Exactly where councils are going to get that money from looks increasingly problematic.
New mayor Andy Foster was relying on congestion charging for some of it, but Transport Minister Phil Twyford has ruled that out.
National has previously said it's open to looking at congestion charging for the city.
Twyford said funding responsibilities for LGWM have been signed off by Cabinet and were not up for grabs.
Transport would be a major issue for the National Party in Wellington and the Hutt Valley this election, Bishop said.
During his speech Bishop said National would outspend Labour on transport infrastructure.
Last month the Government unveiled a package of projects in its $12b infrastructure spend up, called the New Zealand Upgrade Programme.
The spend on transport amounted to $6.8b, with roads making up $5.3b of that.
Bishop wouldn't reveal any specific numbers today but assured the crowd National's transport package would be significant and "bigger and better" than the Government's.
"We are the party of infrastructure and we intend to campaign on that message."