The Mustang version of the V6 was updated for 1999 to use the split port cylinder heads originally introduced on the Windstar. However the 1999–2000 Mustang did not use IMRC, instead leaving all 12 intake runners open at all times. Output of the V6 in these Mustangs was at 5250 rpm and of torque at 2750 rpm. With the addition of IMRC to Mustang in 2001, engine output increased slightly to at 5500 rpm and (305 N·m) of torque at 2800 rpm.