Do u really need to break in an Evolution 46NT, it SAYS it comes pre-run and adjusted from the factory.

Both my evo's ran great out of the box, you may need to make a minor fuel setting adjustment here and there but that should be it.

Have someone experienced check the engine when it runs. Some of the Evos run great out of the box but some come from the factory with the low speed needle valve fully closed! I have one of the 60 size Evo engines and I haven't figured out how to make it run proiperly yet!! [>:]

As has been stated here before, the Evo engines are "run in" at the factory, they are not BROKEN IN!! Do yourself a favor and go through the same break in proceedure you would for any other ABC type engine. As far as the way they run out or the box, both of mine (.46NT and .61NT) I had to readjust the stops for the idle and needle valves just a tad. Take time and read the manual where it covers how to do this in case you need to make some adjustments.