Might be an MPH or two left in it but why bother chasing it. 341.85 should be fast enough, no? Grubnic himself explained how hard it is on the engines to push them to that point. You've got tires on the ragged edge. A catastrophic failure with either one is a 6-figure mistake and dangerous for Brittany too. Might be some ET left in it....Kalitta went 3.62, after all. Focus on that.