4AGE with Eaton Supercharger?

[NoHachi]

Read the info on Billzilla's website. Find the prices for every component, including the headwork. Find and add all prices including the work needed to install them professionally. Find that there is no "cheap" hp in a 4age.

A "little bit" more hp will cost a lot and involve risks about reliability. Imho better left for a project car then a daily. Your catcams example will either require an exhaust, intake, ecu and injectors (possibly, cant remember) or it will not make any power worth talking about. Cost breakdown:

Exhaust+header: 600E if you shop around
Intake: 80E if you shop around and have a good head on your shoulders
Megasquirt+stuff to make it work: 300E if you shop around
Cams: 400E (?)
Springs: 100E (?)
Tuning: 100-200E, includes gaskets and other small stuff.

Money spent: 1600 euros or so..hp? 140 without headwork. Add 300E worth of headwork and you are at around 150hp for around 2000E. Plus the whole things reliability depends on the quality of work..
I still say GZE swap by a professional is one of the most solid ways of improving hp. 20V if you want noise over hp.