Congestion is costing the West Midlands £1 billion a year, according to business leaders, as firms count the cost of two major motorway closures in a week.
Businesses were severely hit after of hours of tailbacks on the M6 through north Birmingham on Friday and Tuesday following crashes.
Greater Birmingham Chamber of Commerce said the cost of road congestion was more than £3 million a day in the region and claimed schemes like HS2 and Midlands Connect were key to easing the burden.
Meanwhile, new data showed 10 major A-roads in the region have average speeds of less than 14mph during rush hour with infrastructure creaking under the sheer number of cars.
The A34 southbound in Sandwell was named as the slowest, with a rush-hour average of just 8.2mph, while Birmingham's slowest route was the A457 Summer Hill road into the city centre, at 12.7mph.
Paul Faulkner, chief executive of Greater Birmingham Chambers of Commerce, said: "Clearly, this is unacceptable but is something that is being addressed in several ways across the West Midlands.
"HS2 will help to ease this problem with the West Coast Main Line being freed up for more freight.
"And Midlands Connect, a regional transport initiative, is to receive £5 million funding from the Government to help iron out these problems. This goes some way to supporting the government's commitment for the Midlands to be ‘Britain's engine for growth'.
"This move helps to reaffirm the Chancellor George Osborne's assertion that future transport investment in the Midlands will help it act as a transport hub for the entire country.
"The funding will go some way to turning this ambition into reality. We are at the heart of the country but we face major problems with our roads and rail connections in many places."
Pictures: Accident on the M6
The problem is compounded by major incidents such as that on Friday when an articulated lorry crossed the central reservation of the M6 near junction seven, bringing the entire motorway and much of north Birmingham and the city centre to a grinding halt for eight hours.
Then on Tuesday a crash between junction five at Castle Bromwich and junction six, for the Aston Expressway left three lanes closed for hours.
A study from driving intelligence firm Inrix and the Centre for Economics and Business Research predicts the annual cost of congestion in the UK will rise by almost two-thirds, to £21 billion, by 2030.
Rob Dale, transport coordinator at Oldbury haulage firm SLD Transport, said there needed to be more focus on road infrastructure in the region.
However, he said roadworks needed to be more efficient, citing the current closure of the M6 junction nine in Wednesbury which was then extended by five months. He said: "On Friday, one of our vehicles was caught right at the front of the tailbacks and he didn't make a single delivery that day.
"We lost money that day, although that doesn't happen that often. It all comes straight out of our pocket - you can't charge customers for traffic."
He added: "More money needs to be spent on the roads but then you get all the roadworks. It feels like there has been roadworks on the M6 for ten years and now they've shut junction nine."
Aside from crashes and roadworks, Wolverhampton has the slowest roads, with the average speed being just 16.4mph, Birmingham is second with a morning commute of 17.5mph, and Sandwell third, where motorists crawl along at 17.6mph.
Colin Leighfield, chairman of the Black Country Chamber Transport Policy Group, said the region's roads were holding businesses back.
Mr Leighfield said: "Businesses are very frustrated by what is an ongoing problem and, although many companies have changed their transport patterns to start earlier in the day, smaller companies find it more difficult to do this and find themselves stuck.
"Our frustration comes from successive inaction from policy makers in local and national government. At a time when the Midlands Engine is competing with the Northern Powerhouse, transport gridlock will make us uncompetitive when it comes to inward investment."