[Dominik]

I scolled up and down: Was the exhaust system mentioned?

While your area under the curve from 2 to 6000rpm is a concern, you can compensate for variations be shifting up differently.

So you actually want the biggest area in the rpm range you drive.
Which might very well be 2.000 to 6.000, same as me!

BTW, must we guess because Gessford built it ;-)