Originally Posted by irondoc

hmm... first off I have never seen anyone other than one report with anywhere near 340 whp non-FI.
Additionally high flow cats and test pipes are for track use - so that is off the table. So subtract roughly 10-20 whp.

In real life - If you look at claimed numbers for the usual suspect non-FI mods you get for cost/HP gains -
Exhaust – roughly 10-20 whp for $1270 plus install
CAI – 12-20 whp, $530 plus install
Headers – maybe 15 whp – 550 plus install
Our car makes 270whp unmodified, so with all of the above you get maybe 45 whp – or 315 total for around $2400 with plus tax and installation, arguably 4K said and done, or $90/whp.

Stillen SC at $7800 for 125 whp is $62/whp – I like that ratio better.

Really I don't see any comparison in power. FI is pricey and if you look at my recent thread Stillen SC long term reports you will see reports so far of close to 500whp with minimal problems.