E120 CREW ENCOUNTERED WAKE TURB FROM A B727 IMMEDIATELY AHEAD.

Narrative

OUR FLT HAD BEEN CLRED FOR TKOF BEHIND A B727 WHICH HAD JUST BEGUN ITS INITIAL CLBOUT. ATC WAS NOT CONCERNED BECAUSE THE B727 IS NOT CONSIDERED 'HVY.' WE ROLLED SLOWLY INTO POS ON RWY 24L IN ORDER TO CREATE SPACE BTWN THE B727 AND OURSELVES. THE TWR CTLR FORCEFULLY TOLD US TO ROLL 'IMMEDIATELY.' THERE WAS NO TFC ON FINAL SO I FIGURED THAT HE WAS IN A HURRY TO LAUNCH THE ACFT BEHIND US. WE FELT THAT SUFFICIENT DISTANCE HAD BEEN CREATED AND WE PROCEEDED WITH A STATIC TKOF. OUR ACFT WAS VERY CLOSE TO ITS MAX TKOF WT. GENERALLY AN E120 CAN CLB STEEPER THAN A B727 BUT TODAY WE WERE ABOUT MATCHED AT 400 FT AGL. WE ENCOUNTERED THE WAKE FROM THE B727. WE IMMEDIATELY TURNED ABOUT 20 DEGS R TO EXIT THE WAKE BECAUSE IT WAS THE SAFEST COURSE OF ACTION. THERE WAS NO TFC WHICH WAS IN CONFLICT WITH US. THE TWR WAS ADVISED OF OUR TURN AND THE WAKE ISSUE WAS EXPLAINED. THE CTLR THEN PROCEEDED TO CHASTISE FOR MAKING AN 'UNAPPROVED TURN.' OUR HDG DEV LASTED ABOUT 8 SECONDS. THERE WAS NO FURTHER INCIDENT.