I was wondering if anyone here has debated/compared the bellmouth design of many downpipes (ie - TSX, Invidia...) with one that uses a split collector to seperate the wastegate and turbine gases like the one B&B Performance Exhaust sells. Does it make a difference? I know they are marketing it as causing less turbulence but so many people use bellmouth designs and have gotten good gains, I am not sure. On one hand I see how it smoothes out the airflow by having it seperate, but then again it may be more restrictive than a 4" bellmouth since it is wide open. Anyone have some insight? I guess I am a semi-noob trying to peice together the best exhaust which will show the best gains.

Thanks

Ro

Not to be rude but do a search. This has been talked about in great length. Remember your 2.5 will react the same to my 2.0 when it comes to exhaust.

The short version: Bellmouth great results. Divorced can sometimes hit the wastegate and cause problems. Divorced can also get some bad boost creep issues if they are not designed correctly. They have no power advantages over bellmouth. Why get something that might cause problems when the other option won't.

300blueballs

http://www.cobbtuning.com/tech/exhaustdesign/index.html

Read down to Nathan,s post
http://www.teamnabr.com/ubbpub/ultimatebb.php?ubb=get_topic;f=9;t=000016

Thanks guys. That definately helps me out and adds to my repitoure of car knowledge. Wombat - that cobb tuning article was very informative. mbiker- I will use the search function next time

Originally posted by mbiker97
Not to be rude but do a search. This has been talked about in great length. Remember your 2.5 will react the same to my 2.0 when it comes to exhaust.

The short version: Bellmouth great results. Divorced can sometimes hit the wastegate and cause problems. Divorced can also get some bad boost creep issues if they are not designed correctly. They have no power advantages over bellmouth. Why get something that might cause problems when the other option won't.

I agree with this 100%.