car is slower with race tube, back box!

1. user_39588 Regular Poster Joined: Dec 2009 bangor north wales Posts: 276 52 plate blue furio

   #1 17th February 2010, 23:40

   hi ive just fitted a sportex 4"back box and race tube but it has gone a lot slower on pick up? would i have to get a mani to see the full potential?
   its a mk2 furio.
   cheers jony
2. coleman258 Established Member Joined: Nov 2008 Eastbourne Posts: 2474 Astra van daily Black Saxo VTR 16v'd kent PT51

   #2 17th February 2010, 23:40

   Thats because you have just but a dustbin on the back of your car.

   4 users thanked this post: Sophia_Bush, Krys_23, user_21226, Slugshead
3. vts-luke Established Member Joined: Dec 2008 North Posts: 1206

   #3 17th February 2010, 23:45

   Quote:

   Originally Posted by coleman258 Thats because you have just but a dustbin on the back of your car.

   no its not.
   the backbox wont be doing anything for performance, the race tube though if its a straight through (de-cat/de-silence) will have taken away some back pressure causing your problem, should have free'd up the rev's higher up the rev band though
4. Krys_23 Saxperience Post Whore Joined: Aug 2007 Posts: 6543

   #4 17th February 2010, 23:51

   Quote:

   Originally Posted by vts-luke no its not. the backbox wont be doing anything for performance, the race tube though if its a straight through (de-cat/de-silence) will have taken away some back pressure causing your problem, should have free'd up the rev's higher up the rev band though

   I've heard some shit in my time but this is in the top 5 x

   2 users thanked this post: Sophia_Bush, Slugshead
5. user_39588 Regular Poster Joined: Dec 2009 bangor north wales Posts: 276 52 plate blue furio

   #5 17th February 2010, 23:52

   Quote:

   Originally Posted by vts-luke no its not. the backbox wont be doing anything for performance, the race tube though if its a straight through (de-cat/de-silence) will have taken away some back pressure causing your problem, should have free'd up the rev's higher up the rev band though

   makes sense but its just really slow its just a load of noise but no go im thinking maybe because its a 48mm pipe and with it still having the standerd mani its losing a lot of pressure entering the race tube? but i dont fancy spending £200 on a mani if i wont see any gains.
   thinking about it i am still running with the standerd air box would that be a problem?
   thanks
6. coleman258 Established Member Joined: Nov 2008 Eastbourne Posts: 2474 Astra van daily Black Saxo VTR 16v'd kent PT51

   #6 17th February 2010, 23:53

   I think he deserves an award for it

   1 user thanked this post: Sophia_Bush
7. vts-luke Established Member Joined: Dec 2008 North Posts: 1206

   #7 17th February 2010, 23:54

   http://www.saxperience.com/forum/showthread.php?t=87854
   read, if you can

   1 user thanked this post: user_39588
8. coleman258 Established Member Joined: Nov 2008 Eastbourne Posts: 2474 Astra van daily Black Saxo VTR 16v'd kent PT51

   #8 17th February 2010, 23:57

   I think maybe you need to read that then re-write your answer.
9. KamRacing Saxperience Addict Joined: Nov 2006 A farm shed in Aylesbury Posts: 14916 Corolla AE86 Peugeot 205 B18C (in bits)

   #9 18th February 2010, 08:00

   48mm exhaust sounds fine to me.. isn't it the standard diameter still!
   
   .. the supersprint ones are 50mm diameter for comparism.
   
   You have a freer flowing exhaust with less restrictions. Usually this pushes the power band slightly higher - ie you'll need to rev it. If you are worried about performance get the car on a RR and see what the results are..
   
   The mani will get you more gains - and correctly matched both that and the exhaust will work together
10. user_10473 Saxperience Forum Bum Joined: Jun 2006 Swansea Posts: 4946 Bianca White Peugeot 106 S2 Rallye, Saxo VTS

    #10 18th February 2010, 08:38

    Lol at the thanks in this thread. It's full of love

    2 users thanked this post: Mochachino, Slugshead
11. Aron Saxperience Forum Bum Joined: Feb 2007 Nuneaton Posts: 3554 EP3 Civic

    #11 18th February 2010, 08:51

    As said there would be no reason for the straight center section to make it slower. If its a Mk2 furioi would have thought it would have the cat in the mani so that will make all the back pressure that is needed.
12. user_39588 Regular Poster Joined: Dec 2009 bangor north wales Posts: 276 52 plate blue furio

    #12 18th February 2010, 17:31

    i thought it would give even a small gain but nothing. ahh well it still drives any way