Glad to hear "Speedtuning" thinks it can stand a bit more - will they replace your engine if their modifications result in a melted piston? Is the extra quarter or half second off the 0-60 time really worth it?

If your car is not fast enough for the wife sell it and replace it with an E430 - W210 turbodiesels are fetching absurd prices on e-bay. You could sell your car replace it with an E430 and have enough $$$ left over to pay for fuel for 5 years.