Feedback from Owners with Kleemann and Evosport Tunes..
MBWorld Fanatic!
Joined: Jul 2009
Posts: 1,103
Likes: 0
From: FL
'09 C63 AMG
From what I've learned over the past several years on modding my cars is NO, 10HP makes virtually no difference in terms of performance (especially on an already very powerful car with 300-400-500HP 
). Now, if you have a highly modded car already and add something else which can add another 10HP to an otherwise stock car, then this mod could possibly add more HP/TQ on the modded car than on a stock car...in which case, it could be worth it. 
Case in point...sometimes, an aftermarket open-air intake on a stock car does nothing in terms of performance gains (maybe it sounds better, but doesn't actually add any HP/TQ); however, put that same open-air intake on on an already highly modded car of the same model, and it may actually add some HP/TQ and could be a decent mod with real HP/TQ gains, especially in the upper speed ranges.
