Upgrading E-class

[MB_AD]

I have 1997 E-class and i want to upgrade it. what is the cheapest way to increase the horse power?

Note: I have fixed a full (FOX) exhaust system and i didn't feel the change in (HP).

What about chip? (Brand and price if you know)

[donau]

Originally Posted by MB_AD

I have 1997 E-class and i want to upgrade it. what is the cheapest way to increase the horse power?

Note: I have fixed a full (FOX) exhaust system and i didn't feel the change in (HP).

What about chip? (Brand and price if you know)

I had two E class Mercedes cars prior to my current car but never thought of modifying them due to voiding the warranty, and I traded before the warranty was up. I did, however, frequent the Brabus website and I know they have ECU upgrades for the E class. I would imagine Carlsson, Kleemann and Lorinser would too.
The exhaust and performance airbox mods do add a little power but I don't believe that it would be enough to feel in the seat of one's pants.
Beyond the ECU, exhaust and air-box mods, with a N/A car one is looking at more expensive and labor intensive exercises like changing cams and valve springs etc. I guess in a N/A car the ECU upgrade would be the way to go.
In a Turbo car it is much easier: the biggest bang for the buck comes from changing your exhaust headers.
I have read from some of the posts here that AlxAmg had modified his Mercedes CL55. Maybe he could be a bit more helpful regarding modifying a MB.