The FX45 comes with the big 4.5L V-8 engine (VK45DE) found on the upper crust Q45 but in this trim it makes 310 bhp and 329 lb-ft of torque (versus 340 bhp and 333 lb-ft of torque in the Q). No big secret but Infiniti did try to keep it hush for awhile, there is the lower cost FX35 utilizing the 3.5L V-6 (VQ35DE) mill found on the G35 and is good for 280 bhp plus 270 lb-ft of torque. Both engines are all aluminum and employ double overhead cams with four valves per cylinder. In other model applications, we've experienced both engines and can attest they are silky smooth and deliver gobs of power when needed.
All models come with a 5 speed automatic transmission with a manual shift mode. FX45 and FX35 AWD models utilize the ATTESA E-TS system found originally on the Japanese Skyline GT-R sportscar. The system is also found on the current QX4 (called All-Mode AWD for that application). According to our sources, ATTESA E-TS consists of a variable electronic torque-split transfer mechanism. It directs torque to the forward drivetrain through a multi-plate clutch. The clamping force on the clutch varies between 0-50% dependant on wheel speed sensors that measure slip and a lateral G-force sensor. For the FX series, we're assuming that the system will send most of the power to the rear wheels until slip is detected and then a varying amount of power is sent to the front to improve grip. Thus the FX acts as a sporty rear wheel drive vehicle until adverse conditions cause the AWD to kick in.
