Here's a few dyno charts, same runs, stock vs. added bolts ons (Encore Innovation X-pipe with High Flow Cats, Rogue Engineering Pulley and an AFE filter, on 91 octane. Dyno's were done at VF-Engineering in Anahiem, CA.
We see dyno charts posted from time to time, some here maybe unsure about correction factors, as you can see below there can be a decent size difference depending on how it's presented, the standard should be SAE.
Regardless the mods added as much as 30WHP & 20WTQ over the stock car!
With race fuel and a tune, I believe 20 - 25 more WHP is possible.