We were really impressed with the way the MaxTurbo system fits on and around the untouched 4.6. That's right: with the exception of the turbo, this Mustang's bullet is completely stock, as are the automatic transmission and 8.8 rearend. All of the OEM accessories (power steering, A/C, and so on) have been retained and are fully functional. Matt credits DiabloSport's tune for the awesome driveability. We saw steady 180-degree engine temp during our cruise-with air conditioning blowing ice-cold in the passenger area.