I've had my balance shaft elimination kit in for about 45,000 or so. It was very easy to install (included illustrated instructions). After it was in I couldn't tell ANY increased vibration BUT I had just rebuilt the engine, and the pistons and rods were carefully balanced before installation. I don't know what effect it would have on an engine where the pistons/rods weren't balanced.

But in my case, I've had no vibration related issues since install.

Lee

1987 Raider 2.6L Auto -- rebuilt, by hand, by me -- Bouncy Seat/LSD/Aisin Hubs -- CB/Whip Antenna --Jensen Stereo -- Fire extinguisher .