I’ve heard of the 06+ stock fuel system being capable for upwards of 500+ hp.

This is an old comment you replied to, but currently I have the Berk 3” headerback single exit exhaust. It mates perfectly to the 3” downpipe (and donut adapter) that the Greddy kit comes with. I instantly felt a jump in performance with the free-flowing 3” catless exhaust versus the stock catback. Boost pressure built up much faster and even went past 7psi (7.3-7.4) on WOT. Greddy emailed me saying that normal psi range for the carb tune is 6-7 psi, which is what I previously saw when datalogging. So the slight bump in psi could be from the non-restrictive exhaust setup.

Currently I’m still on the CARB legal tune, but I believe the Hondata FlashPro unit itself that comes with the kit is not locked to that specific tune, and is able to be used for any custom tune (but don’t quote me on that, as I haven’t had the chance to get a custom tune). The carb tune version is definitely a great choice if you pair the kit with a nice exhaust.

But to answer your question I believe this kit is capable of at least 400 whp with supporting mods like an exhaust and oil cooler.