General Car Related Discussion. To discuss anything that is related to cars and automotive technology that doesnt naturally fit into another forum catagory.

Manifold question, how to pair up branches

Thread Tools
 
Search this Thread
 
Old Jun 8, 2013 | 07:41 PM
  #1  
StephTell's Avatar
StephTell
Thread Starter
Too many posts.. I need a life!!
 
Joined: Oct 2007
Posts: 882
Likes: 4
Default Manifold question, how to pair up branches

Question:

I'm busy building a custom bike with a 4-pot engine.

Now ideally I want to pair up two cyllinders into a two-into-one exhaust on either side for looks, but I also don't like the 4-pot sound through open pipes so I'm wondering if it would be good to pair the cyllinders up the way you would if you'd be making a twin-scroll manifold, i.e. 1 and 4 and 2 and 3?

Would it still run right (I don't know why not to be honest) but more importantly; would it alter the sounds a lot and make it less recognisable as a 4-pot?
Reply
Old Jun 8, 2013 | 07:45 PM
  #2  
botters's Avatar
botters
competant bodger
iTrader: (2)
 
Joined: May 2009
Posts: 6,234
Likes: 23
From: preston
Default

i may be wrong but im sure a twin scroll runs 1+3 4+2 as per firing orders ?
Reply
Old Jun 8, 2013 | 08:35 PM
  #3  
StephTell's Avatar
StephTell
Thread Starter
Too many posts.. I need a life!!
 
Joined: Oct 2007
Posts: 882
Likes: 4
Default

That's what I ment lol
Reply
Old Jun 8, 2013 | 09:04 PM
  #4  
botters's Avatar
botters
competant bodger
iTrader: (2)
 
Joined: May 2009
Posts: 6,234
Likes: 23
From: preston
Default

lol thought so, would be worth looking into what scoobys run as its the manifolds on them that give the notorious off beat scooby sound
Reply
Old Jun 8, 2013 | 09:08 PM
  #5  
the_frozen_one's Avatar
the_frozen_one
Too many posts.. I need a life!!
iTrader: (1)
 
Joined: May 2012
Posts: 842
Likes: 2
From: Crawley, West Sussex
Default

It's the unequal length of the manifolds on the 2 banks on scoobie manifolds that create the sound. They sound totally different on equal length systems
Reply
Old Jun 8, 2013 | 09:14 PM
  #6  
botters's Avatar
botters
competant bodger
iTrader: (2)
 
Joined: May 2009
Posts: 6,234
Likes: 23
From: preston
Default

Originally Posted by the_frozen_one
It's the unequal length of the manifolds on the 2 banks on scoobie manifolds that create the sound. They sound totally different on equal length systems
thats what im getting at mate, might be worth trying something similar on the bike if he wants something that does not sound like your average 4 banger
Reply
Old Jun 9, 2013 | 07:18 AM
  #7  
StephTell's Avatar
StephTell
Thread Starter
Too many posts.. I need a life!!
 
Joined: Oct 2007
Posts: 882
Likes: 4
Default

Food for thought!

Unequal lenght wouldn't be such a problem to create but what sort of lenghtdifference is needed, percentagewise?

Also, it's fuelinjected engine but I have no control over each cyllinder seperatly so would it cause problems? Iguess not as a standard scooby doesn't either?
Reply
Old Jun 9, 2013 | 07:48 AM
  #8  
stevieturbo's Avatar
stevieturbo
C**t
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Oct 2003
Posts: 7,998
Likes: 269
From: Norn Iron
Default

Of course the subaru has full sequential fuel injection.

Really, just build it whatever way looks best. Unless you're trying to extract every ounce of power/torque for winning races....it will hardly matter.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
liamT74
General Car Related Discussion.
10
Sep 23, 2015 10:24 PM
BRAMMER
Ford Sierra/Sapphire/RS500 Cosworth
15
Sep 14, 2015 08:52 PM
Bransby
Ford Escort RS Turbo
5
Sep 11, 2015 01:09 AM
andrewmctiernan
General Car Related Discussion.
0
Sep 8, 2015 03:05 PM




All times are GMT. The time now is 08:35 AM.