THE PLT OF AN ATX SMA TWIN HIT TURB ASSOCIATED WITH TSTMS IN THE AREA AND INADVERTENTLY TURNED OFF THE R MAGNETO TO THE R ENG. THIS CAUSED HIM TO THINK THAT THE ENG WAS POSSIBLY GOING TO FAIL. HE DECLARED AN EMER AND STARTED TO DIVERT. THIS LED TO A SERIES OF MANEUVERS WHICH SOMEWHAT COMPLICATED HIS SIT. HOWEVER; HE FINALLY RECOGNIZED THE SOURCE OF HIS ENG MALFUNCTION AND CORRECTED IT AND CANCELED HIS EMER.

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ON SEP/XA/97; I DEPARTED TUS ARPT; RETURNING TO MY HOME BASE OF BLANDING; UT. AT APPROX 50 NM N; I ENTERED AN AREA OF TWRING CUMULUS CLOUDS AND SCATTERED SHOWERS. I DECIDED TO CLB ABOVE THE CLOUD BASES TO FIND SMOOTH AIR WHEN I ENCOUNTERED VERY STRONG TURB FOR A SHORT TIME. I REDUCED AIRSPD AND CONTINUED MY CLB LOOKING FOR SMOOTH AIR. AFTER A COUPLE OF MINS; I AGAIN ENCOUNTERED STRONG TURB. AFTER THE TURB SUBSIDED I NOTICED AN UNUSUAL ENG INST INDICATION. THE R MANIFOLD PRESSURE INDICATED SEVERAL INCHES HIGH. I REHEARSED (REVIEWED) THE SINGLE ENG EMER PROCS AND MADE SURE ALL LEVERS AND SWITCHES WEREN'T DISTURBED. I AGAIN RAN INTO STRONG TURB AND DECIDED TO MAKE A PRECAUTIONARY LNDG AT GLOBE; AZ; ARPT. I WAS WORRIED THE R TURBO WAS MALFUNCTIONING AND WANTED TO LAND. BECAUSE OF TWRING CLOUDS AND LIMITED FORWARD VISIBILITY AND INTERMITTENT TURB; I REDUCED PWR A LOT TO DSND. IN ORDER TO DSND MORE RAPIDLY AND PROTECT THE R ENG; I REDUCED ITS PWR TO IDLE. WHILE MANEUVERING TO FIND GLOBE ARPT; I INADVERTENTLY GOT VERY CLOSE TO TWRING CUMULUS CLOUDS AND R2310A&B. WHILE MANEUVERING TO FIND GLOBE; I SQUAWKED 7700 AND DECLARED AN EMER ON 121.5. AS I APCHED THE MOUNTAIN NEAR GLOBE; I REALIZED THAT THE R MAGNETO ON THE R ENG WAS TURNED OFF. I TURNED IT BACK ON AND WAITED FOR ANY STRANGE SIGNS. THEN I GRADUALLY INCREASED PWR TO MATCH THE L ENG AND AGAIN WAITED FOR STRANGE SIGNS. I THEN REALIZED THAT I MUST HAVE HIT THE MAGNETO SWITCH DURING SOME TURB AND TURNED IT OFF. I CANCELED MY EMER ON THE RADIO AND SQUAWKED 1200 AGAIN AND RESUMED NORMAL NAV TO MY HOME BASE. I EXPERIENCED NO FURTHER PROBS WITH THE ACFT.