Does anyone make a Carb legal Long header for 4x4 nbs models?
And if not Carb legal, can you tune it post install to make it it pass smog somehow?
True LT headers on our GMT800 trucks require relocating the cats further back, which violate federal law, so therefore they are not legal in any state and only legal for off-road use. Even in states with no emissions check, if you encounter a state trooper who wants to screw with you and knows the law, he could legaly still ticket/impound you.
With the proper tune, they can easily pass emissions, its just the visual check that fails you.
There are some midlength headers that don't need cat relocation, but they are not true LT's.