After ST2009, I started thinking about the Kelvin and her top speed since she is a single-nacelle vessel. I believe she is a Warp-5 vessel. In TOS, Enterprise and others have two nacelles and are capable of speeds up to Warp-8 (and 9 in a pinch). Later we see ships with three nacelles, most notably the Enterprise-D from "All Good Things". Does having more nacelles equate to a speed boost? Have we ever seen a ship with four or more nacelles?
Well, certainly the designer of the USS Hackwrench would have us think so.
Seriously, I've always been under the impression that the extra nacelles gets you longer warp flight time, because it takes the operational strain of generating warp fields and divides it among the extra nacelles.