You (and you car) are already experiencing 1g of downward force as you sit there, due to graviy. The Motor Trend analogy of "opening a trap door" seems appropriate if suddenly you are experiencing approximately 1g of forward force.
Just like the old theories that we couldn't break the sound barrier, (and the earth was flat) people used to think that cars couldn't break 1g acceleration (because you only have 1g of downward force for traction). Dragsters routinely beat 1g now for many reasons including wings to push down more than 1g and tires that glue themselves to the road surface.
I think 1g of sustained forward force might get you to 60mph in about 2 seconds. Since the roadster doesn't have big wings, suction fans, or drag race tires, I suspect it would have trouble keeping traction to do that. 0 to 60 in 3.x is likely right at the limit of the street tire traction capabilities.
Roller coasters that start off with high forward g's tend to have electric motors of pneumatic pistons to directly push them so they are not traction limited.
Some G-force related info here:
g-force - Wikipedia, the free encyclopedia
"The record for the highest
g force on a roller coaster belongs to
Mindbender at
Galaxyland Amusement Park,
Edmonton, Alberta, Canada, at 5.2
g. The highest
g on a thrill ride can be experienced on
Detonator at
Thorpe Park, which reaches 5.5
g at the end of the drop by firing riders downwards pneumatically. Fuji Q Highland, an amusement park in Fujiyoshida, Yamanashi, Japan, used to operate a shuttle coaster named
Moonsault Scramble that subjected riders to 6.2
g in the track's high speed pretzel element. The Texas Tornado reached 6.7
g."
"Aerobatic and fighter pilots may sometimes experience a greyout between 6 and 9
g"
"Formula One drivers usually experience 5
g while braking, 2
g while accelerating, and 4 to 6
g while cornering."
Some example number crunching can be found here:
Falling Lexus Commercial - Topic Powered by eve community