I have the Bosh +4 platinums on a stock engine. I haven't had any problems or complaints for over 10K miles. I have MSD Blaster coil and Ford 9MM wires.
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Scott93GT
1993 Mustang GT
Silver CC/Titanium Accent GT, Black Clothe interior.
5 speed, 3.08's, 3 chamber Flows, K&N, Hurst Competition Plus.
1991 F150 4x4 XLT Lariat
Six Stick Regular Cab LWB Tow Vehicle