will having 2.25 or 2.5 inch pipin really make that big a difference compared to stock piping??? Someone please explain why its better to have larger diameter piping,... More flow obviosly but is it really that big a difference?

 

If you have a stock motor, bigger piping may actually hurt you, If you go dohc with some kind of forced induction you will see benifits, but it is loud...

 

So having a Cat back on a stock SiR is useless?

 

drink through a cocktail straw and a mcdonalds straw and come to your own conclusion.

 

So for a B18C1 is 2.5 overkill? Would I not have enough pressure if I did that? Am not too sure how it works either

 

Something to do with backpreassure, im assuming?? someone pls elaborate.

 

back preasure helps with maintain a high level of torque on the bottom end but as ur rpms rise so will ur exhaust..so on the top end ull gain hp..i would go beyond 2 1/4 for NA or a blower..but if ur going turbo id say go with a hi flow cat and 2 1/2

 

How big is the stocking piping again?

 

is that would or wouldn't... I got lost- stupid me. So you think 2 1/2 is overkill for a NA B18C1 (sorry, it just isn't clicking today)

 

Bolt-ons..2.25 is fine. If you up the compression I`d go 2.5".

Ryan

 

Thanks

 

So the purpose of a catback exhaust is have larger then stock diameter piping? Im just wondering if I need to get a new mid section for my axl back.

 

Yes..........

 

2.25" works best of NA hondas

 

I think mine is already 2.25 stock (99-00 Si\SiR)... Correct me if im wrong..


[Modified by Soichiro Honda, 11:14 PM 12/2/2002]

 

SIR? I do belive its 2.25, Also most cat backs are " manderal bent" for better flow.

 

sorry..bad me..i meant i wouldnt go beyond 2 1/4 piping for NA