1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Downpipe Question

Discussion in 'Forced Induction' started by 92civicb18b1, Mar 25, 2005.

  1. 92civicb18b1

    92civicb18b1 The Trisexual

    Messages:
    8,859
    Likes Received:
    18
    Joined:
    Oct 1, 2003
    Location:
    The asshole of the USA, New Jersey
    Well, I have a 2.5" DP and a 2.5" Exhaust.

    Would it be beneficial if I made a 3" DP?
    Wouldn't it just bottle neck after the cat?
    How exactly would I mate it to the flange? With a reducer?

    I'm not ready to buy a whole new exhaust but I figure I might as well make the DP my first pre-start upgrade if it's worth it.

    Explaination, opinions, thoughts, criticism
     
  2. formby

    formby learning in progress

    Messages:
    5,735
    Likes Received:
    23
    Joined:
    Feb 19, 2003
    if you have a muffler man special, i would go with the 3in...if not then 2.5 is fine.
     
  3. b204dr

    b204dr Senior Member

    Messages:
    915
    Likes Received:
    0
    Joined:
    Oct 11, 2004
    Location:
    Minnesota
    how is your exhaust going to be running - cat/catless? with a stock cat you will bottleneck for sure-

    if you are using a racing cat/test pipe there wont be quite the bottle necking issue due to free flow- but as we know its annoying and i dont know how things will be about noise polution in your area
     
  4. pissedoffsol

    pissedoffsol RETIRED

    Messages:
    49,693
    Likes Received:
    53
    Joined:
    Sep 28, 2002
    Location:
    Retirement Home
    it won't choke as much, but it will still choke. 2.5->3 vs 2.5 all the way back is pretty marginal in difference.

    you shoudl go all 3" :)
     
  5. b204dr

    b204dr Senior Member

    Messages:
    915
    Likes Received:
    0
    Joined:
    Oct 11, 2004
    Location:
    Minnesota
    yea- but i was just thinking with him meaning temp. it wouldnt be that bad -
     
  6. 92civicb18b1

    92civicb18b1 The Trisexual

    Messages:
    8,859
    Likes Received:
    18
    Joined:
    Oct 1, 2003
    Location:
    The asshole of the USA, New Jersey
    i dont really want to get a new exhuast yet, but I'll defenitly think of making a 3 inch DP.


    I'm have a test pipe.

    I could careless about noise pollution or emission for that matter.

    I have a PA registered car in NJ. They can eat my ass, they can't give me an emissions ticket anywhere unless I'm in philly, stroudsburg, harrisburg or Pittsburg, PA.
     
  7. reckedracing

    reckedracing TTIWWOP VIP

    Messages:
    21,056
    Likes Received:
    1,180
    Joined:
    Dec 5, 2002
    Location:
    NY
    i think it would help to have the 3" down pipe... then convert the rest to 3" when you get a chance...

    better to have the restriction further from the turbine...
     
Verification:
Draft saved Draft deleted

Share This Page