well I think I'm gonna go with 2.5. Sounds like mixed reviews and perhaps 2.25 but perhaps 2.5. Only way to know for sure, without some simulation software, would be try both out. Since I have way too many other things to do on this car I'll just pick 2.5 and be done with it. Maybe in the future I'll try out some things but for now this'll do.

here's another question. How far down do you put the crossover? I assume it'd the be same point whether you use an X or an H since the wave reflection is gonna happen at the point where the pipe opens? Or perhaps there's more to it than that? Seems to me that this would be a critical point