I have a 2011 Tucson 2.4 GLS Fwd. If you have the Fwd version of the Tucson with the 6spd auto, you will notice that its decently quick. I have a GPS based performance meter and I have measured a 0-100km/h time of 8.2 seconds on regular fuel with outside temperature at around 10 degrees Celsius. Using Shell 91 octane at also around 10 degrees celsius I was able to achieve 0-100km/h in 7.9 seconds. On shell 91 fuel I was able to get the Tucson up to 210km'h. The Tucson has about 18k on it so the engine is well worked it. I did a little upgrade using a performance air filter which I had for an old Audi A4. Its a universal K&N cone filter. I was unsure how to connect the K&N filter with the factory intake hose until an idea came while making soup. The soup can was the exact diameter as the stock intake hose, and I opened the can with a can opener on both ends and used the can as a bridge between the filter and stock intake. Now with the new filter and using 91 octane fuel my GPS performance meter measured 0-100km/h in 7.5 seconds and a top speed of 217km/h. No check engine light after almost 4 months of use, in addition to the quicker acceleration, I am averaging about 30km more per tank. So its a win win situation. A third win factor is these filters are washable, just buy a cleaning kit for $20 and the filter is good for as long as you own the car. Here are some pics of my installation. The filter retails for about $40 and the soup can I wrapped in black vinyl electrical tape for aesthetics.