A C172 PLT MADE A PREMATURE TURNOUT CONTRARY TO NORMAL ARPT PROCS.

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CFI (MYSELF) WAS MAKING TKOF FOR CURRENCY. AS WE TAXIED UP #2 FOR TKOF BEHIND AN ACR (FOKKER F100); I CALLED READY TO GO. TWR QUERIED ACR IF HE WAS READY; BUT HE TOLD TWR THEY WERE WAITING FOR WT AND BAL INFO. WE WAITED A COUPLE OF MINS AND I TOLD TWR I COULD BACK TAXI FOR INTXN TKOF. SHORTLY THEREAFTER; ACFT CALLED READY AND TWR CLRED HIM FOR TKOF. WE GOT A POS AND HOLD; THEN CLRED FOR TKOF SHORTLY THEREAFTER. I PLANNED TKOF ON UPWIND SIDE OF RWY (ABOUT 500 FT R QUARTER HALF WAY) AND LIFTOFF BEFORE F100 ROTATION POINT TO AVOID WAKE. AS WE STARTED TKOF ROLL; TWR CAUTIONED ABOUT WAKE TURB. I LIFTED OFF; CLBED STEEPLY; AND ABOUT 1/2 WAY DOWN RWY DECIDED TO TURN OUT EARLY TO OUR ASSIGNED HDG OF 320 DEGS TO MAKE SURE I AVOIDED WAKE TURB. I HAD ABOUT 500 FT AGL AND WENT BTWN PAX TERMINAL AND TWR (ABOUT 1/2 MI BTWN). BEFORE OUR TKOF; TWR HAD BEEN TALKING TO OTHER LNDG TFC AND I THINK HAD CLRED THEM TO LAND; SO I HAD HURRIED TKOF TO GET OUT OF THE WAY (IE; GET OFF QUICKLY). THAT TFC WAS APPARENTLY A COUPLE OF MI OUT AND PERHAPS ON A WIDE DOWNWIND/BASE; AND ASKED TWR WHERE DEPARTING TFC WAS. TWR ADVISED HIM THAT HIS TFC HAD TURNED A BIT EARLY; SO I WONDERED IF TWR WAS UPSET I HAD TURNED EARLY WITHOUT ADVISING. TWR NEVER SAID ANY MORE; BUT I FELT PERHAPS I SHOULD HAVE CALLED PRIOR TO TURN SINCE I DIDN'T GO TO DEP END OF RWY BEFORE TURN. IT WAS A QUICK JUDGEMENT CALL; AND I DIDN'T ASK FIRST DUE TO CONCENTRATING ON TKOF. I DIDN'T WANT A 4 MIN DELAY FOR WAKE TURB AFTER WAITING BEHIND F100 TO GET HIS WT AND BAL DATA AND FIGURED HIS WAKE WOULD DRIFT AND SETTLE. TWR APPARENTLY DIDN'T SEE A PROB EITHER; EXCEPT FOR A SLIGHTLY DELAYED WAKE TURB WARNING. NO DANGEROUS STUFF REALLY OCCURRED IN THIS CASE; AND A SIMPLE CALL ON MY PART WOULD HAVE PREVENTED THE ISSUE ARISING.