standard exhaust produces more torque then afternarket one?

1. logic_guy Saxperience Forum Bum Joined: Nov 2010 England Posts: 3423

   #1 9th March 2013, 20:22

   I have fitted mk1 under car cat and silencer to my supersprint manifold and kam racing backbox.
   
   It feels a hell of a lot more torque and picks up speed quicker even though it has a cat and silencer that would reduce exhaust gasses escaping. My girlfriend too has noticed this.
   
   I'm wondering why it feels a lot more power then a straight through exhaust?
2. welshpug Saxperience Forum Bum Joined: Jul 2010 South Wales Posts: 3078 ZX 16v, 205 GTI, 309 Goodwood, 405 MI16.

   #2 9th March 2013, 20:29

   pulse tuning.
3. logic_guy Saxperience Forum Bum Joined: Nov 2010 England Posts: 3423

   #3 9th March 2013, 20:35

   Pardon mate? I'm english
4. Quick Saxperience Post Whore Joined: Mar 2003 United Kingdom (England) Posts: 7064

   #4 9th March 2013, 20:48

   Pulse tuning indeed!
   
   Read up on it, google could be your friend!
5. welshpug Saxperience Forum Bum Joined: Jul 2010 South Wales Posts: 3078 ZX 16v, 205 GTI, 309 Goodwood, 405 MI16.

   #5 9th March 2013, 21:03

   I'm Welsh
   
   google it indeed, basically the standard engine and camshaft was designed for use with that chamber opening up at that point in the exhaust, remove that point and the pulse is moving at a different frequency.
   
   very same principles as changing bore sizes and diameter of primaries to secondaries and lengths of the pipes.
6. logic_guy Saxperience Forum Bum Joined: Nov 2010 England Posts: 3423

   #6 9th March 2013, 21:05

   It takes me to a place in sydney. As I understand it, its the variables of the exhaust and these can be used to produce more power?
   
   I'm still not clear how a Cat and a Silencer in the way and make it a lot more quicker.
7. user_43898 Established Member Joined: May 2010 leicester Posts: 1446 Clio 182 Inferno

   #7 10th March 2013, 10:11

   I noticed this when swapping my stuff back over to have the cat back on. But not sure its actually faster with the cat in. Santapod times different y0 no seriously..
8. m4tt274 Saxperience Forum Bum Joined: Sep 2011 Doncaster Posts: 2627 Fabia VRS, mk1 fiesta + some others

   #8 10th March 2013, 17:30

   You have more back pressure. It would be be in keeping with most tuning theory if you found that your car makes more power lower down in the rev range, but you will had less at the higher revs.