As a result, a number of elements in the AWD driveline must often be upgraded to handle the increased power output. Everything in the driveline receives more stress simply because there is less wheel spin.
While the increased traction provided by an AWD configuration is key to maximizing acceleration, it is also delivers significantly more stress to the driveline. Now, E85 has proven to allow tuners to make “race gas” power at high boost levels with a fuel you can get at the pump. Up until the introduction of E85 to the pump, 91- or 93-octane fuel simply didn’t allow the boost pressure necessary on small displacement engines to make “9-second” power.
Some believe that any car that needs race gas to achieve its performance goals isn’t a streetcar. Since there is no universally agreed upon definition for a streetcar, everyone has a different opinion. Selecting a turbocharger capable of the required power levels while strengthening the engine to survive at these elevated cylinder pressures is part of the 9-second equation. Being turbocharged, both the EVO and GT-R have the ability to produce power that is double, triple or even four times the output of a naturally-aspirated engine of the same displacement. By the end of the quarter-mile, the traction advantage of the AWD often equates to an elapsed time that is a full-second quicker than a FWD or RWD vehicle with an identical power to weight ratio and power curve. On street tires, most AWDs will have at least a half-second advantage over FWD and RWD vehicles in the 60-foot times. In many cases, a GT-R or EVO will deliver a 60-foot time (which is a great indicator of the vehicle’s ability to suddenly deliver power to the ground) on street tires that is even better than a RWD or FWD vehicle on racing slicks. In the case of a FWD vehicle, the weight over the front tires is reduced during the “launch”, limiting traction even further. When a FWD or RWD vehicle launches and the balance of weight shifts over the drive wheels, the total amount of available traction also changes. On a FWD or RWD vehicle, only the contact patches of the two drive wheels factor in the straight-line traction equation. Being AWD, an EVO or GT-R is able to use all four-contact patches as traction points to propel the vehicle. Both cars are all-wheel drive (AWD), both feature turbocharged engines, both run on E85 and both rely upon reinforced drivelines to deliver 9-second performance. In looking at either the GT-R or EVO, a number of similarities become apparent.