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Tim.duncan
7th December 2010, 03:01 PM
are bip port and small port exhaust ports the same?
ie can i get a set of extractors for a bigport if i have a small port?

also i know its been covered a milllion times but what size exhaust is perfect for a NA 16v? is 2.5inch to large?

cheers

Skylar
7th December 2010, 03:58 PM
The port exit sizes and spacing are the same for bigport, smallport and 20v although the 20v has the two outermost holes on the flange further out than 16v.

Guy at exhaust shop I use says 2.25" for daily, 2.5" if you're going to be in the upper revs a lot of the time.

xero
7th December 2010, 05:04 PM
2.25" is a good all round size, and 2.5" if its a real angry motor or a race car...

Tim.duncan
8th December 2010, 10:54 AM
cheers

LittleRedSpirit
8th December 2010, 11:00 AM
I think some people get a bit excited on the whole exhaust size thing. Smaller is better, unless you are going to be building some kind of monster with 9 million duration cams and forty feet of lift that revs to a million rpm. Its still a 1600.