Notices
ScoobyNet General General Subaru Discussion

can you modify a 2.5" backbox to fit a 3" center section?

Thread Tools
 
Search this Thread
 
Old 11 August 2018 | 01:25 PM
  #1  
the shreksta's Avatar
the shreksta
Thread Starter
Scooby Regular
iTrader: (20)
 
Joined: Apr 2011
Posts: 8,445
Likes: 497
From: hinckley
Default can you modify a 2.5" backbox to fit a 3" center section?

ive just had a 3" center section fitted along with a raptor backbox as on my previous impreza's thats what i had and i loved the sound BUT on my current impreza it just doesnt sound as good, i actually prefer the sound of the vortex box that was removed.

would headers and up-pipe make it sound different as this one has a decat up-pipe and standard headers.

my only option really is to modify the vortex i removed to fit my current 3" section, there is a custom exhaust place near me that i would use, would it dampen performance going from a full 3" down to the 2.5" at the back box?

perhaps they could chop off the 2.5" pipe work all together from the vortex and weld on some 3" pipework.

Old 11 August 2018 | 03:09 PM
  #2  
Henrik's Avatar
Henrik
Scooby Regular
iTrader: (5)
 
Joined: Jun 2003
Posts: 4,135
Likes: 147
From: London
Default

There are adaptors that are sleeve fit 3" and 2.5" flange. I'm pretty sure the one I have in the garage is a jetex part.

you'd have to cut the 3" section flange off, but it should be possible to use a sleeve as above.
Old 11 August 2018 | 03:17 PM
  #3  
Henrik's Avatar
Henrik
Scooby Regular
iTrader: (5)
 
Joined: Jun 2003
Posts: 4,135
Likes: 147
From: London
Default

Can't seem to find one now off the shelf online

However could use something like this: https://m.ebay.co.uk/itm/Exhaust-Adaptor-Reducer-Joining-Sleeve-Connector-Any-Size-/111083884881?_mwBanner=1&_rdt=1
Old 11 August 2018 | 03:43 PM
  #4  
Don Clark's Avatar
Don Clark
Scooby Regular
 
Joined: Feb 2003
Posts: 7,640
Likes: 772
From: Harpenden
Default

Old 11 August 2018 | 04:38 PM
  #5  
rsjohn's Avatar
rsjohn
Scooby Regular
iTrader: (3)
 
Joined: Sep 2005
Posts: 1,031
Likes: 0
Default

Sell me the raptor???

Sorry had to ask.
Old 11 August 2018 | 08:28 PM
  #6  
the shreksta's Avatar
the shreksta
Thread Starter
Scooby Regular
iTrader: (20)
 
Joined: Apr 2011
Posts: 8,445
Likes: 497
From: hinckley
Default

Originally Posted by rsjohn
Sell me the raptor???

Sorry had to ask.
if i take it off then yes i will.

im trying to replicate the sound of my previous imprezas but i cant seem to do it
Old 11 August 2018 | 08:29 PM
  #7  
the shreksta's Avatar
the shreksta
Thread Starter
Scooby Regular
iTrader: (20)
 
Joined: Apr 2011
Posts: 8,445
Likes: 497
From: hinckley
Default

Originally Posted by Henrik
There are adaptors that are sleeve fit 3" and 2.5" flange. I'm pretty sure the one I have in the garage is a jetex part.

you'd have to cut the 3" section flange off, but it should be possible to use a sleeve as above.
would there be a performance restriction going from 3" downpipe/center into a 2.5" back box?

i know you can go 2.5 into 3 inch but not sure about the other way around
Old 11 August 2018 | 08:30 PM
  #8  
the shreksta's Avatar
the shreksta
Thread Starter
Scooby Regular
iTrader: (20)
 
Joined: Apr 2011
Posts: 8,445
Likes: 497
From: hinckley
Default

thanks buddy will keep that in mind
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
beenyman
Subaru Parts
14
08 October 2020 12:54 PM
Dannymot
General Technical
8
01 September 2016 02:38 PM
RB5_245
Wanted
1
13 October 2006 09:33 AM
Scott.T
Drivetrain
7
28 February 2003 06:16 PM
IAN LOVETT
Drivetrain
5
02 October 2000 01:05 AM




All times are GMT +1. The time now is 11:30 PM.