which of the hearders would make more porwer. 4-2-1 or 4-1. and what is so deffernt about them.

 

The difference is where it makes power. 4-2-1 is more for midrange and throughout the power band. 4-1 is more top end.

 

Neither make more power. They allow the engine to breathe better which inturn produces more power. The type of exhaust manifold you'd get would depend on the type of motor you have. GSR's would do well with 4-2-1 but would excel with a 4-1 where the engine's typically reving in the high end. an RS/LS/SE/GS would do better with a 4-2-1 as the low and midrange are where the b18b benefits are. You might feel a loss of power on the low end if you went with a 4-1