Been looking seriously into supercharging my RS4, so far the potential company is MTM although the prices are a little scary to say the least. So was looking for any kits out there to see if there was a more "affordable" solution. I have found one, check this out..... Audi RS4 Supercharger Kit Electric RS4 Turbo Charger Bolt On How much power do you think that will add? Think that will be far better than the MTM one....* *PS. I am being sarcastic but was laughing so much I had to share it.