A property developer lost control of his prized Ferrari car after he revved the engine so his girlfriend could hear the sound, an inquest heard.
Motorsports fan Benjamin Gladman, 31, died in the crash near Marlingford in Norfolk on 25 January.
His girlfriend Barbara Zart was injured but survived.
Former prime minister David Cameron, who was on a shooting weekend nearby, was among the first on the scene and his close protection officers, who are trained in first aid, tried to help.
Lord Cameron was not mentioned at Thursdayâs inquest in Norwich, but the efforts of police officers in an unmarked vehicle were described.
Yvonne Blake, area coroner for Norfolk, said Mr Gladmanâs mother Dr Hilary Sporton and twin brother Matthew Gladman described him as a âbeautiful, generous soul who cared so much about othersâ.
Reading from a joint statement from the family, Ms Blake said Mr Gladman and his brother were business partners and had started a property development firm in Norwich.
Mr Gladmanâs address was given as Brentwood in Essex, but the hearing was told he lived near to where he crashed.
The twins âshared a huge love for motor racing, including Formula Oneâ, the family said.
âThe boys even bought a Ferrari as an investment.â
The statement read by the coroner said the Ferrari 360 Challenge Stradale had a 3.6-litre petrol engine and the brothers âwere always careful and respectfulâ when driving it.
Ms Zart said in a statement read by the coroner that her partner âwanted me to go out with him in his car, the Ferrariâ.
âIt was his favourite car, he had wanted since he was a little boy,â she said.
âEven though he doesnât really use the car, it was an investment. He had it serviced every year.â
She said they had planned to drive into Norwich for coffee and âBen had driven the road where the accident happened lots, he lived in the villageâ.
âI remember Ben wanted to show me the sound of the engine because itâs like the race engine,â Ms Zart said.
She said he would normally drive at 30mph but may have been driving at 50 to 60mph that day, still within the 60mph national speed limit for that section of road.
âI remember the car started to lose control,â she said.
A forensic collision report gave the time of the crash as 2.52pm, and noted the car had spun and hit a tree.
Peter Humphries, who was fishing nearby at Melton Ponds fishing lakes, said he âheard a very loud engine revvingâ.
âIt lasted no more than five seconds then there was a loud bang,â he said.
He described the revving as âoff the chartâ and âunbelievably loudâ.
Pc Alan Gould, who was driving an unmarked Land Rover Discovery, said he came across the crash and stopped to help, with fellow officers providing first aid.
Ms Blake said Mr Gladman died of multiple severe traumatic injuries in the crash at Bow Hill.
She said the motorist, who had adopted a husky cross rescue dog called Dobby, was a âFormula One enthusiastâ.
âHard-working, sounds like he was a thoroughly nice man in a happy relationship,â she said.
âGoes out to take his girlfriend out in his car, wants her to hear what it sounds like.â
She said police officers noted the muddy verge âmay have contributed to the lack of gripâ but that âwe donât know exactly whyâ the car left the road.
The coroner recorded that Mr Gladman died as the result of a road traffic collision and told his mother: âIâm so sorry that youâve lose your son in this horrendous way.â
Loved ones who attended Thursdayâs hearing at  Norfolk Coronerâs Court did not wish to comment afterwards.
