Blown Diffusers
A ‘blown diffuser’ refers to the exhaust manifold designed to take advantage of the exhuast gases leaving the engine and forcing air onto the rear diffuser. The diffuser is the rear underside plate that controls the airflow between the air over the top of the car and the air beneath. This creates ‘upside-down lift’ similar to the of an airplane wing except in reverse. The maximum amount of down-force can be applied to the race car here which is arguably where most of the F! performance is said to come from. In 2009, the winner championship car from Brawn GP was notorious for their double diffuser which arguably gave them the fastest car in F1 and consequently their championship.
Here’s a sneak preview of what a blown diffuser exhaust looks like compared to a normal exhaust system.
Blown Diffuser
Blown Diffuser
At the beginning of 2010, Christian Horner was asked about what he thought of other teams copying his ‘blown diffuser’. He replied, “I’m flattered that when other teams copy what you’ve done. It’s fortunate for us that this is where the least amount of performance is!” Clearly, this was a bluff as most of the big teams have now copied their blown diffuser and have nearly caught up to Red Bull. A lot of other aerodynamics are in play as well but the ‘trick’ diffuser is clearly the biggest advantage. It’s not as easy as copying a blown diffuser though, a lot of teams now have the challenge of making this new aerodynamic advantage work. There is some talk of specific retardation of the engine on off throttle that plays a key part to stability around corners (red bulls advantage is superior cornering together with grip to the rear tyres)
