"Bobsleigh is like Formula One and it costs a lot of money to have fast equipment," Radjenovic, also 31, tells CNN.
"So like a Formula One team, if you don't have a lot of money to invest in it, it is hard to do well, which has made it hard for us."
The addition of Pittman has helped raise funds, reaching a target of $A20,000 ($18,000) to help buy a new sled.
Sponsors were invited to support the "Icebirds" -- which is the nickname the team adopted for branding and publicity purposes.
"Astrid advertised on our Facebook page," Pittman says. "A little competition on names and then people voted. It gave us an identity a team name, so certainly helped with our support."
Pittman said they had also resorted to some unusual training methods in the quest for success.
"We push shopping trolleys in our backyard, we train at a normal athletics track because we don't have snow and we don't have ice, so for Australians to make the Olympics in bobsled is pretty much a 'Cool Runnings' all over again," she says.
That Hollywood film about the Jamaican bobsleigh team in the 1988 Winter Games in Calgary may well act as an inspiration, but during her storied career in track and field, Pittman was rarely the underdog.
Already a world youth champion, she went to her first Olympics on home soil in Sydney in 2000 and won Commonwealth Games gold two years later in Manchester.
Then came world championship success in Paris but in the buildup to Athens she picked up a knee injury that required surgery just before the Games.
Despite the disadvantage, she still managed a creditable fifth place in the final, although that was little consolation at the time.
Further Commonwealth Games success in Melbourne in 2006 was tempered during the course of the year by a very public row with 4x400m relay teammate Tamsyn Lewis, which led to adverse publicity for both athletes.
Pittman was reportedly ready to leave Australia and by then she was married to Britain's former champion hurdler Chris Rawlinson, giving birth to their son Cornelis Levi later that year.
Relenting on the threat -- "I've always been a very proud Australian" -- and coached by Rawlinson, Pittman dominated the 400m hurdles in 2007 and won her second world title in Osaka.
However, injuries again took their toll on her Olympic hopes, and her relationship with Rawlinson also soured. After a brief reconciliation they have separated again, leaving Pittman to face life as a working mother.
"I'm studying medicine full-time and I have a little boy who is seven, but for me, having him in my life is so grounding and I feel like I have a very full, loved life so I will certainly not go to my grave with any fears or regrets," she says.
That also extends to her track and field career, despite missing out on her ultimate goals.
"I've been very lucky that I've been to two Olympic Games and won two senior world titles, so it's certainly been a wonderful career and I'm very grateful for the opportunity."
Pittman also has no intention of fading quietly into retirement post-Sochi, and wants to maintain her partnership with Radjenovic on the World Cup bobsleigh circuit.
"I know that Astrid wants to retire but I'm still trying to get her to go another year," she says.
"I've really found something that I love in bobsleigh. It is a great sport, the people in this sport, even from other countries, are really together, they really help you on every possible angle and I think I'd love to stay in this sport if possible."
Failing that, Pittman has also hinted at a return to track and field -- although she would have to shed the extra muscle that is such an asset in bobsleigh to be competitive in running events.
That would appear not to offer much of an obstacle for a young woman who is renowned for being singleminded with athletic excellence in mind.
In 2010 she caused a stir by revealing that she had undergone surgery to remove breast implants, feeling they were affecting her performance on the track.
"Every time I raced I panicked about whether I was letting my country down, all for my own vanity," she was quoted as saying at the time.