Geared turbofan gas turbine engine architecture

A gas turbine engine comprising:

• a fan including a plurality of fan blades rotatable about an axis, and a low fan pressure ration across the plurality of fan blades alone of less than 1.45;
• a compressor section;
• a combustor in fluid communication with the compressor section;
• a turbine section in fluid communication with the combustor, the turbine section including a fan drive turbine and a second turbine, wherein the second turbine is disposed forward of the fan drive turbine and the fan drive turbine includes a plurality of turbine rotors with a ratio between the number of fan blades and the number of fan drive turbine rotors is between 2.5 and 8.5;
• and
• a speed change system configured to be driven by the fan drive turbine to rotate the fan about the axis at a different speed than the fan drive turbine;
• wherein the fan drive turbine has a first exit area and rotates at a first speed, the second turbine section has a second exit area and rotates at a second speed, which is faster than the first speed, said first and second speeds being redline speeds, a first performance quantity is defined as the product of the first speed squared and the first area, a second performance quantity is defined as the product of the second speed squared and the second area, and a performance ratio of the first performance quantity to the second performance quantity is greater than 0.5, and the performance ration is less than or equal to 1.5.