Officials told ABC News they found no alcohol on the scene and couldn't confirm reports in the media that the group had been drinking in celebration of one of the victims' 19th birthday the night of the crash.
But less than six hours before the accident, a user who called himself "AmericanM5" logged on to a BMW M-5 online forum asking for advice on how to make the 500-horsepower car go faster.
Florida newspaper the Star Banner identified the user as 18-year-old Ammirato.
"The problem is when I'm going pedal to the metal pushing 140 and upshifting, there tends to be thud noise with the gear change," AmericanM5 wrote in one post, adding, "Let me say I am beginner when it comes to high-performance cars as I am only 18 so take it easy on me."
Others on the online forum doubted AmericanM5's claims of owning such a high-powered BMW at such a young age and warned him to take it slow.
A member logged in as "M5Froth" wrote, "Its [sic] just disturbing to know, if you're for real, that an 18 year old who is asking these questions about a 500hp car is driving the same street I am. I don't have anything against young guys driving nice cars, but an 18 year old behind the wheel of an M5 is what accidents are made of IMO."
In his last entry on the forum, posted at 12:33 a.m. Saturday, AmericanM5 wrote, "I completley [sic] understand where you are coming from assuming that I am irresponsible.. that is definetly [sic] understandable. I do sometimes make bad decisions but I am young and I do drive safe and I will not endanger the lives of others.. and I hope you are not under the impression that I am the one to brag, I have never been that way and never will."
This weekend residents mourned the victims who they said formed part of a tight group of friends.
"People are really just in shock," Quelland told ABC News. "Number one, the severity of the crash and just how devastating that was, but people aren't used to losing three people that they're close to at once."
Students from North Marion and others gathered at a Baptist church Saturday to remember the victims, according to local media reports.
"We wanted to have a place where everyone could get together and mourn," Kathy Crile, the mother of a former student and friend of the victims, told the Star Banner. To "hug and cry."