Car of the Day - Ford Shelby GT500 Mustang SVT 2011

Car of the Day - Ford Shelby GT500 Mustang SVT 2011

Ford - are finally giving the Shelby GT500 Mustang an alloy block for 2011, not that there was all that much wrong with the old cast-iron lump from a power perspective. The problem was just weight, and therefore efficiency. Given that efficiency is the name of the game in this age the move is somewhat overdue.

The new 5.4 litre engine is based on the block form the Ford GT however that incarnation of the engine was never considered suitable for the GT500 as it was not deemed strong enough for the drag race set to modify in the way they are accustomed to. That and the fact that it was set up for dry sump lubrication. What has changed in recent times is that Ford has developed a new cylinder bore coating process for alloy blocks called, Plasma Transferred Wire Arc (PTWA). This process involves heating a steel coating material to 35,000 degrees Fahrenheit and then spraying it onto the aluminum cylinder bores to a thickness of 150 micron. Nissan licensed the process from Ford for the GT-R’s V6

The result of replacing the steel cylinder liners with PTWA means the new V8 engine is 102 lbs lighter than 2010 cast iron engine, while still being at least as strong and suitable for drag race style modifcation and power output. The PTWA costing also aids efficiency and output with peak power now at 550 hp, a 10 increase in horsepower Overall there has been a 120 pound weight reduction The new wheels from the SVT Performance Package are 4.7 pounds lighter each at the front. The rears are now 20 inches and 2.8 pounds lighter than the old 19’s. The weight reduction both over the front axle and to the unsprung weight has obvious benefits to handling and dynamics and helps give the new GT500 a more balanced feel.

The SVT package includes a 3.73:1 rear axle to cater to the larger rear wheels and the suspension has been modified to take advantage of the reduction of weight over the front axle. The front springs on the SVT are 20.5-percent stiffer while the rear are 9.5-percent. The GT500 is now 11 millimeters lower at the front and 8 mm at the rear.

For those that love the sunshine, one of the most important changes for the 2011 model line is that SVT have significantly increased the convertibles body rigidity, bringing it much closer to the Coupe in overall performance and feel.

Of great significance as well is that the efficiency of the new coating on the cylinders as well as the weight reduction has resulted in the 2010 GT500’s fuel economy (?) of 14 mpg city and 22 mpg highway see a 1 mpg improvement in each area which is just enough for it to be excluded from the EPA’s $1,000 gas guzzler tax

Rod Halligan