boost pipes size

  1. Frequent Poster Joined: Apr 2010 Kent Posts: 755
    #1
    what size boost pipes would you guys recommend to use with a 106 gti turbo? intercooler core size is 550mm x 175mm x 64mm

    inlet and outlet is 2.25"

    i know people use either 2", 2.25" and 2.5" pipes

    i wil be using a gt25 turbo starting on low boost and then later be uprating internals to forged and then turn the boost up a bit

    i am asking as i dont want to end up having pressure drop etcc
  2. Saxperience Addict Joined: Jul 2005 Solihull / Bournemouth Posts: 14233 2015 Lapiz Blue Golf R
    #2
    I'd go with 2.25"
  3. Frequent Poster Joined: Apr 2010 Kent Posts: 755
    #3
    was thinking that mate as its kinda in between then lol, would the 2.25" be ok if i wanted to upgrade to a gt28 to run a bit higher boost?
  4. Super Moderator Joined: Nov 2009 Cambridge(ish), UK. Posts: 10581 BMW 5x M50d.
    #4
    use whatever size outlet you have from the intercooler for the easiest installation. In your case, 2.25". I have 3" outlet from the intercooler, so will be running constrictors down to 2.5" and running 2.5" for my setup.
  5. Saxperience Hardcore! Joined: Oct 2008 Birtley Posts: 22253 VTR Turbo, 106 xsi track slag, Transit recovery, B
    #5
    i would just save and do the lot at once, i was gonna go low oost but its just twice the expense in the long run
  6. Administrator Joined: Dec 2002 Warrington Posts: 20561 Blue Saxo VTS Turbo/White Megane F1 R26
    #6
    I'd run the outlet a little larger than the inlet... So 2in and 2.25 out.
  7. Saxperience Addict Joined: Jan 2007 Aylesbury, Bucks Posts: 12836 Yeaaahh Fiesta
    #7
    2.25 would be the optimum on a low boost setup
  8. Saxperience Post Whore Joined: Feb 2006 dudley United Kingdom (England) Posts: 6790 106 gti/ SEAT LCR
    #8
    2.25 will be PLENTY.