I'm installing a Rips 4" system this morning and need to know which way to put the muffler on? It doesn't have an inlet or outlet marked. The differences are when you look inside is that one way all the little "scoops" will be used or if I flip it around the other way, the "scoops" will get passed over.
I don't want drone....so which way should I put it? My gut is telling me to use the scoops...
Please let me know what you know......I'm right in the middle of the install!
Thanks

 

just tack it in place and go for a run..then do what sounds good to ya

 

If you place it so the openings inside the muffler are pointed upstream its a little quieter. With the openings downstream its a little louder.

 

Thanks for the replies...I went with the tab "upstream"...to keep the neighbors happy! The old system was wasted!