VANOS is a good thing. It advances the timing at higher RPMs to squeeze out a little more power and lengthen the power band. While it's a little tricky to adjust and it's sometimes known to rattle when the parts get old and worn, a properly running VANOS engine will give you more bang for your buck. Non-VANOS engines are good for one reason, forced induction. If you plan on later installing a supercharger or turbo, you might look into getting a non-vanos motor. However, you should keep in mind that if you do decide to install a FI setup later down the road, you're likely going to want rebuild the engine and replace all of the worn internal parts anyway. I recommend looking for a VANOS equipped M50 simply because you're likely to find one in better condition with less mileage than a non-vanos one. |