Reading deep into threads about Duratec Mazda L engines. Sounds really exciting right? These are in Escapes, Fusions, Mazda 3's and 6's, and the Transit Connect. The aftermarket scene for these are scarce. But I am seeing multiple conversations about removing the balance shaft on this engine to free it up a little bit. The shaft itself is almost 20 pounds; so you’re reducing weight, and letting the engine spin more freely.

This is the underside of a 2.3 Ecoboost
Image: JW Racing

There’s even a removal plug kit to block up the oil feed to the now absent shaft. The reviews are mixed. Some are saying the only downside is the risk of additional NVH (noise, vibration, harshness) at lower RPMs. Others claim you can do catastrophic damage if you don’t re-balance the crank after removing it. Has anyone here done work like this? Any thoughts from the gallery?

Image: Amazon