1. The Turbo Forums - The discussion board for both hard core and beginner turbocharged vehicle enthusiasts. Covering everything from stock turbocharger cars, seriously fast drag racers, boats, motorcycles, and daily driver modified turbo cars and trucks.
    To start posting in our forums, and comment on articles and blogs please

    IF YOU ARE AN EXISTING MEMBER: You can retrieve your a password for your account here: click here.

Wastegate ?

Discussion in 'Turbo Tech Questions' started by 01somta, Apr 17, 2006.

  1. 01somta

    Joined:
    Sep 20, 2005
    How do you determine the correct size of wastegate that you will need? Right now I have a 300rwhp n/a car, I have a mp T70 and plan on running between 10-12psi. Will a 38mm be too small? I have a stock block still so I am limited on how much boost I can run. Sorry guys for the ignorant question, but I truly used the search button and could not really find the answer that I was looking for.

    Thanks Dustin
     
    01somta, Apr 17, 2006
    #1

  2. 01somta

    Joined:
    Sep 20, 2005
    also if the wg has a .3 (5 psi) spring in it, what is the max. amount of boost that I can run with that spring or is there a max?
     
    01somta, Apr 17, 2006
    #2

  3. 01somta

    Joined:
    Sep 20, 2005
    ttt
     
    01somta, Apr 18, 2006
    #3

  4. mystang

    Joined:
    Mar 17, 2004
    alright as far a size the lower boost you want to run the smaller wastegate you can run, because with higherboost, you are wanting less exhaust to bypass the turbo. As fa a size what size engine are you running? now for max pressure you 5 will be your max unless yo get a boost contrroller, then you can prettymuch make as much as you wannt, but if you are going to run 12 pounds of boost then get a 12 pound spring.
     
    mystang, Apr 18, 2006
    #4

  5. turbostang

    Joined:
    Jun 29, 2003
    The less boost you want to run the bigger the wastegate needs to be.

    If you use a smaller spring than the boost level you intend on running, fine - BUT - if the turbo is imporperly sized, exhaust restrictions, turbine backpressure etc.. you will find that the boost controller can not pump enough pressure on top of the wastegate to overcome the turbine backpressure and will eventually blow the gate open no matter what. Most likely won't happen at 10-12 psi though.
     
    turbostang, Apr 18, 2006
    #5

  6. 01somta

    Joined:
    Sep 20, 2005
    It is a 302 and I plan on running 10-12 psi. So would a .3bar be ok? The way I understand it is that you can run more than the number on the spring but just no less.
     
    01somta, Apr 18, 2006
    #6

  7. turbostang

    Joined:
    Jun 29, 2003
    It should work pretty good for ya.
     
    turbostang, Apr 18, 2006
    #7

  8. Cld12pk2go

    Joined:
    Jan 25, 2004
    I have a 0.4Bar spring that I believe is the causing me to not be able to run above 11 PSI sustained. I can peak at ~13.4 PSI around 3300 RPMs then it will taper off to ~11 PSI by 5000 RPMs. I do have a restrictive 0.68 A/R p-trim turbine housing coupled with a far less than optimal exhaust, which I believe is compounding the situation.

    The compressor should certainly not be my limiting factor, thus my suspicion about the wastegate being forced open by high backpressure.

    So I would say the answer is "It depends".
     
    Cld12pk2go, Apr 18, 2006
    #8
Loading...
Similar Topics - Wastegate Forum Date
Wastegate plumbing Turbo Tech Questions May 4, 2024
Wastegate plumbing need advice Turbo Tech Questions Jan 29, 2024
How to fix a leaky Wastegate? Turbo Tech Questions May 25, 2023
Loading...