For a good getaway vehicle which is the fastest 4-seater car in Grand Theft Auto 5?
As @turbo mentions in the comments below acceleration is also an important consideration.
I've just discovered and trawled through this helpful site which lists all of the GTA5 vehicles: https://googledrive.com/host/0B-Q7WnzcPvLtLVVoM3otTVlnOFE/all.htm
It looks like the faster 4 seater is the Ubermacht Oracle 1 - with a speed of "8.1" and an acceleration of "6.8". Although there are many cars with a speed of "8.0" (but not as good acceleration).
After a bit more homework I've also identified these two cars - the Bravado Buffalo (cheap and plentiful) and the Dewbauchee Exemplar having very similar speed and acceleration stats - but better traction:
I should add that after months of playing the game my "go to" 4-door is the Lampadati Felon for it's handling. The Felon is rare but stealable so can be used as the primary car from the beginning of the GTA Online campaign.
It is also worth noting that as of the I'm Not a Hipster Update, the Bravado Buffalo S, or Franklin's Buffalo, can be purchased from southernsanandreassuperautos.com for $96,000. It has the same stats as the Dewbauchee Exemplar, but a faster acceleration at "7.5". http://gta5.consolegameswiki.com/wiki/Bravado_Buffalo_(Franklin)
Felon it handles pretty well and has a higher acceleration than the oracle and sultan and has a better top speed than the sultan.
Karin Sultan fully modified. In a straight line with enough space it will go eventually faster than an Adder.
The Obey tailgater is a nice handling car and can be brought in to online mode by the tutorial
The tailgater is a nice car fully modified and can be a nice 4 seat car for you.
If prefer the tailgater it has good speed and acleration so you can find it when Simeon wants it or can bring it online
I would choose the Exemplar. But check out is full list of 4-seaters: http://www.gtaguru.com/best-4-seater-cars-in-gta-v/
As of heists in my opinion the Karin Kuruma beats all of them it goes fast, is bulletproof and is an overall beast.
Thank you for your interest in this question.
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