2.6 class
 

will a 66mm turbo pass for 2.6 class cause i believe its 2.59=66mm if not whats a good 2.6 class turbo

Yes it's a 2.65 plug so you have a hair to play with. Only 66mm I've seen have trouble passing is a silver bullet, but they stil passed it.

some do some dont. mine didnt but my buddys from the same company did

Some days mine will pass some it won't. Just to be sure always have something really cold with you and have engine at a cool temp for tech time. These two steps will help just tell the manufacturer what your plans are and it needs to fit the plug right. It bit me at Terra Haute this year when it was warm just missed it by a hair.