Best combination of headers and cat back’s

[86TOYO2k17]

Yes you are absolutely right comparing % increases is much better.
But looking at a ton of dynos and figuring out what mods, % increases, variables etc can get overly complicated. And having more simplistic numbers for easy comparison can be nice.
If these are all dynos on 2017s then the expected gains would be roughly 5hp less, or rather 5hp more for 2012-16

I wouldn’t be surprised if the numbers I stated If tested on a 170hp baseline dyno for a 2012-16 would be pretty accurate. And your dynos you posted seem to reflect that from a % standpoint?

Although maybe I am under selling the ace+dt with and without E85?

[CSG Mike]

Here's another perspective, that shows street driving manners being improved.

[Lantanafrs2]

This will never end