not a TON bigger, but it with the bigger wastegate, it can hold and produce more air flow.

install....there is not difference really, unless the GT25R has a different bolt pattern to the exhaust mani or cat.

Reliability...eh, k04 is a OEM part. But Garrett makes some pretty strong and reliable stuff.

Smooth ride...depends on software. K04 will have more power down low and will push you back in your seat a bit more. GT25R, will have more lag therefore you wont have the power at 2500RPM like you would in a k03 or k04. But the power comes on smooth and pulls harder, much faster.

What software would you like into for the GT25R? suporting mods??

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