Gerald Hoekstra, 46, and his navigator Ede Taric, 50, died after their buggy hit a tree and rolled during a race in northwest Victoria in September 2022.
In her findings on Wednesday, Victorian Coroner Ingrid Giles found both men survived the crash - during the Rainbow Desert Enduro race - but died moments later, after their vehicle went up in flames.
Ms Giles identified no breaches of the Motorsport Australia standards, but called for them to be strengthened to prevent future incidents.
Mr Hoekstra's widow Deborah told AAP she had not yet read the findings but had long believed her husband did not have to die.
"I still firmly believe that a lot of things could have been prevented," she said.
The coroner heard the buggy's fuel tank had an exposed filler neck with no valve to stop fuel escaping.
When the vehicle rolled, petrol spilled onto the surface surrounding it and ignited, most likely from the heat of its catalytic converter.
Ms Giles found the fire would likely have been prevented had a reflux valve been present.
Other competitors stopped and emptied six hand-held fire extinguishers onto the wreck, but could not extinguish the flames.
Ms Giles found the one kilogram extinguishers were insufficient to combat the flames, which continued to burn until fire crews arrived 12 to 13 minutes after the crash.
Motorsport Australia has since tightened its rules, including requiring fuel tank openings to sit inside a vehicle's protective frame.
Ms Giles commended the governing body for making changes since the crash, claiming they had removed the need for extensive coronial recommendations.
But she took issue with its plan to phase-in "plumbed-in" fire extinguishers over three years, insisting the rollout should instead be immediate.
She also recommended mandatory testing to confirm competitors can escape their vehicles within 10 seconds and clearer rules on what firefighting equipment must be on hand during events.
Ms Hoekstra said she hoped the findings would spark real change in the racing community.
"I don't want anybody to feel the way that we feel," she said.
Her late husband had raced sprint cars for two decades before switching to off-road buggies, a hobby Ms Hoekstra was immediately sceptical of.
He assured her the Desert Enduro race was to be his last, she said.
The event has not been held since the crash but other off-road races continue on nearby tracks.
8°C