[imported_Corey]

I know both have some good power but would the GTI with a 30 mpg rating be better than the mustang?

 

[dalen]

The GTI is a much better car than the Mustang even without consideration of the gas mileage.

If the GTI gets 30 mpg what does the Mustang V8 get? Look it up.

 

[Jem]

You can use a car performance simulator, to run some test with that cars.

Try it at http://www.nxgtrsim.com

 

[huntington]

I have an 04 GTI 1.8T, and yes, the fuel mileage is MUCH better than a Mustang GT. I average 26-27 mpg (with a lead foot) and I've gotten up to 32 mpg in daily driving, even mix of streets and highway.