ConclusionIt may seem as though a Bentley Speed is the last car that would need a bump in power, but we are talking about a 5,200-pound car. The stock car will hit 60 in right around 4 seconds; without actual testing we would guess that the 91-octane version will slip right under the magical 4-second barrier and the 103 will certainly do it.
As with all GIAC software, several options are available with your flash a la carte. Customers can choose what they think will work best for their car and their needs. Programs are selected via a handheld switching module that plugs into the factory OBD-II port found in the driver side foot well. It is all push button and extremely straight forward.
Cost of Parts91/93-octane GIAC performance calibration: $4,100Handheld switching code: $800103-octane race gas calibration: $300OEM "stock" mode: $200Valet mode: $200Immobilizer: $200Privacy firewall: $200Total $6,000
Work = Cylinder Pressure x Piston Area x Piston StrokeThe importance of ignition timing is often overlooked. Timing the spark and consequently the combustion process is absolutely essential for maximizing power. Higher-octane fuel actually burns slower, allowing more timing advance to be used. This allows the tuner to time the ignition sequence closest to the ideal position of the piston, roughly 20 degrees after top-dead center.
Owners who do decide on a flash will not only see an increase in the level of brute-force acceleration but driveability and part throttle response will also be improved. Because of the level of development on the car from the factory, there aren't many hard parts available that will make substantial performance gains. If you're lucky enough to own one of these cars and you want it faster, software is definitely the best alternative.