The quickest spells I saw in the flesh were from James Pattinson and Mark Footitt. What was really impressive with both of these was that they sustained their pace through the full day.
The usual names apart from that - Garton looks rapid, Archer has the potential to be, though when I saw him at Hove last year his pace dropped markedly as the day went along, to the stage that he was not much more than medium pace in the final session. Jamie Overton could get up there if he was ever fit, though a word of caution that he strikes me as a bowler lacking in craft.
What else? If Matt Fisher gets another season without injuries, he will be back up around 90mph, though he is more of a McGrath type bowler.