Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

Turbocharger intercooler piping size

Discussion in 'VT - VX Holden Commodore (1997 - 2002)' started by KalebM, Jun 6, 2018.

  1. KalebM

    KalebM Member

    Messages:
    127
    Likes Received:
    1
    Trophy Points:
    18
    Joined:
    Mar 16, 2018
    Location:
    Australia
    Members Ride:
    Vt v6 3.8 commodore
    So i just recently bought a t3t4 turbo and from what i know it is 2” off the turbo into the intercooler piping would i keep all the piping at 2” or should i get a connection for 3” intercooler piping
     
  2. Pollushon

    Pollushon Boost gives me a bar....

    Messages:
    2,068
    Likes Received:
    118
    Trophy Points:
    63
    Joined:
    Nov 9, 2012
    Location:
    Canberra
    Members Ride:
    VY SS
    What's it going on? There's a few variables but some pretty solid calcs based on the flow rate and your power goal.
     
    Last edited: Jun 6, 2018
  3. KalebM

    KalebM Member

    Messages:
    127
    Likes Received:
    1
    Trophy Points:
    18
    Joined:
    Mar 16, 2018
    Location:
    Australia
    Members Ride:
    Vt v6 3.8 commodore
    So its a vt commo and i was looking at 10psi tops i recon, i dont plan on putting through to much boost
     
  4. _R_J_K_

    _R_J_K_ Well-Known Member

    Messages:
    3,865
    Likes Received:
    178
    Trophy Points:
    63
    Joined:
    Dec 20, 2008
    Members Ride:
    Zenki S14
    General rule of thumb I've seen on a lot imports is turbo outlet sized piping to the intercooler, then T/B sized piping from the outlet of the intercooler to the T/B. By going bigger on the hot side you introduce more volume that you need to fill up before you hit boost. By making it the same size as the outlet you're not restricting flow and minimising volume. TBH though, the lag wouldn't really be noticeable if it was a short length of piping (and even then really if it was long).

    Are you going to tune it?
     
    KalebM likes this.
  5. KalebM

    KalebM Member

    Messages:
    127
    Likes Received:
    1
    Trophy Points:
    18
    Joined:
    Mar 16, 2018
    Location:
    Australia
    Members Ride:
    Vt v6 3.8 commodore
    Yeah i am before dont wanna **** anything up with not enough fuel and **** most likely ill get a aftermarket ecu instead of tuning the stock one, and cheers that helps heaps
     
  6. Pollushon

    Pollushon Boost gives me a bar....

    Messages:
    2,068
    Likes Received:
    118
    Trophy Points:
    63
    Joined:
    Nov 9, 2012
    Location:
    Canberra
    Members Ride:
    VY SS
    You'll wanna up your pump lph for boost, there's no getting around it. OEM pump will leave you short. Walbro 342 and an fpr800 reg works a treat up to about 18psi. Stock delco is more than sufficient for a stock Eco just needs the right tuner.

    This vid is the best I've seen on explaining pipe sizing but your intercooler size is important too. Balance of velocity, turbulence and lag. Sometimes it's just balancing the wallet though.

     
  7. KalebM

    KalebM Member

    Messages:
    127
    Likes Received:
    1
    Trophy Points:
    18
    Joined:
    Mar 16, 2018
    Location:
    Australia
    Members Ride:
    Vt v6 3.8 commodore
    Yeah ive just been looking at that knew i had to upgrade the pump but i thought that i would also need to upgrade the injectors correct? Cheers for the video ill check it out when i get the chance
     
  8. KalebM

    KalebM Member

    Messages:
    127
    Likes Received:
    1
    Trophy Points:
    18
    Joined:
    Mar 16, 2018
    Location:
    Australia
    Members Ride:
    Vt v6 3.8 commodore
    Pressed post twice
     
  9. Pollushon

    Pollushon Boost gives me a bar....

    Messages:
    2,068
    Likes Received:
    118
    Trophy Points:
    63
    Joined:
    Nov 9, 2012
    Location:
    Canberra
    Members Ride:
    VY SS
    Yeah injectors too. Which ones depend on your boost. 10 pounds should be covered by Bosch 36lb.
     
    KalebM likes this.
  10. KalebM

    KalebM Member

    Messages:
    127
    Likes Received:
    1
    Trophy Points:
    18
    Joined:
    Mar 16, 2018
    Location:
    Australia
    Members Ride:
    Vt v6 3.8 commodore
    So ive been recommended to probaly keep the boost under 7-8max for my engine would you know what size injectors i would need for that by chance?
     
  11. Pollushon

    Pollushon Boost gives me a bar....

    Messages:
    2,068
    Likes Received:
    118
    Trophy Points:
    63
    Joined:
    Nov 9, 2012
    Location:
    Canberra
    Members Ride:
    VY SS
    You need to stop talking to whoever it is that's telling you this stuff. Ecos love boost. I rammed 14 pounds into mine for years :)

    Super 6 36lbs would suit.
     
  12. delcowizzid

    delcowizzid on holiday

    Messages:
    6,656
    Likes Received:
    233
    Trophy Points:
    63
    Joined:
    Jul 8, 2008
    Location:
    NZ
    Members Ride:
    в∞ѕтεכ √&
    Just step it up to 3in at the turbo and use the same size all the way to the throttle.36lb will go to 8psi or so 42 to about 12psi j7st but big injectors off the bat or you end up rebuying over and over .
     
  13. KalebM

    KalebM Member

    Messages:
    127
    Likes Received:
    1
    Trophy Points:
    18
    Joined:
    Mar 16, 2018
    Location:
    Australia
    Members Ride:
    Vt v6 3.8 commodore
    Yeah your probaly right it was just because its stock at the moment and didnt wanna put too much power but if you think it wont kill it that would be sick, and cheers i think i might use 3” but from the video that was send it suggested around 2,25” to 2.5” Id say if i went 3 “ itll have a small amount of lag
     
  14. Mike Litherous

    Mike Litherous Active Member

    Messages:
    276
    Likes Received:
    130
    Trophy Points:
    43
    Joined:
    Jan 18, 2016
    Location:
    Melbourne
    Members Ride:
    VE ssv
    Run as big a pipe as u can. All my pipe on the vortech bmw 540i runs 3” for about 600bhp. Prob min 2.5” but the larger pipe u run the less static pressure (air resistance) u have so effectively the less boost u lose due to the high pressure plumbing.
     
    KalebM likes this.
  15. KalebM

    KalebM Member

    Messages:
    127
    Likes Received:
    1
    Trophy Points:
    18
    Joined:
    Mar 16, 2018
    Location:
    Australia
    Members Ride:
    Vt v6 3.8 commodore
    Ok ill probaly use the 3” then recon itll fit should it be the hole piping or 2.5” to the intercooler then 3” ?
     
  16. delcowizzid

    delcowizzid on holiday

    Messages:
    6,656
    Likes Received:
    233
    Trophy Points:
    63
    Joined:
    Jul 8, 2008
    Location:
    NZ
    Members Ride:
    в∞ѕтεכ √&
    The engine runs 3" inlet pipe standard no point going smaller.turbo hits hard as hell and just breaks the tyres loose on 3 inch anyway lol
     
  17. KalebM

    KalebM Member

    Messages:
    127
    Likes Received:
    1
    Trophy Points:
    18
    Joined:
    Mar 16, 2018
    Location:
    Australia
    Members Ride:
    Vt v6 3.8 commodore
    Ok lol so ill do full3” piping and for fuel injectors i was thinking of just the 36lb injectors because the waste gate opens at 7.5psi, and when i go bigger later ill just rebuy them... ill get over the money
     
  18. Mike Litherous

    Mike Litherous Active Member

    Messages:
    276
    Likes Received:
    130
    Trophy Points:
    43
    Joined:
    Jan 18, 2016
    Location:
    Melbourne
    Members Ride:
    VE ssv
    36 lb/hr only gives about 310bhp on 6cyl @ 3bar fuel pressure. I’d probably go slighly bigger and use an adjustable FPR and if u have too much fuel trim the fuel pressure down. That way if u wack up the boost u have some margin for error. Depends how u are adjusting fuel but the injectors these days can function well at low duty cycles.
     
  19. delcowizzid

    delcowizzid on holiday

    Messages:
    6,656
    Likes Received:
    233
    Trophy Points:
    63
    Joined:
    Jul 8, 2008
    Location:
    NZ
    Members Ride:
    в∞ѕтεכ √&
    You doing buick or ecotec .they really wake up above 10psi here' an old vid
    Have since gone 370rwkw on 20psi
     
  20. delcowizzid

    delcowizzid on holiday

    Messages:
    6,656
    Likes Received:
    233
    Trophy Points:
    63
    Joined:
    Jul 8, 2008
    Location:
    NZ
    Members Ride:
    в∞ѕтεכ √&
    You doing buick or ecotec .they really wake up above 10psi here' an old vid
    Have since gone 370rwkw on 20psi
     

Share This Page