Low boost

Discussion in 'SVT Forum' started by hotcobra03, Oct 29, 2008.

  1. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    My 03 is low on boost.i have installed a new bypass solenoid and new vaccum harness.the boost will only go up to the t in boost,it does respond when you hit it and i hear whine.UM mentioned adjusting the actuator.other than this piece can a blower wear out inside?
  2. Uncle Meat Banned

    Member Since:
    Jun 13, 2002
    Message Count:
    3,869
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Prattville, Alabama
    Yup. The lobes inside the blower case are machined to very tight tolerences and over time can wear and reduce boost. You may want to look into sending your blower off to Stiegemeier for a refresh. They'll make it like brand new again.

    StiegeSplash


    U.M.
  3. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    My luck its gonna need rebuilding.how tight should belt be?the ac belt was new and very hard to get on,blower belt is fairly new but during that engine nightmare was removed several times,would that be noticable .
  4. Uncle Meat Banned

    Member Since:
    Jun 13, 2002
    Message Count:
    3,869
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Prattville, Alabama
    If you were getting belt slippage there would be a large buildup of rubber under the belt guard (if still installed) or on the underside of the hood directly in line with the upper pulley if guard is not installed.

    U.M.
  5. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    Can u school me on actuator?manual shows adjusting tool but isnt very clear on fine details.with tool on turn something till rod touches reinstall actuator than remove tool.have you or anyone else done this.
  6. Uncle Meat Banned

    Member Since:
    Jun 13, 2002
    Message Count:
    3,869
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Prattville, Alabama
    I've never done this adjustment personally. I read that the bolts on the actuator can be loosened and then the actuator can move up or down which adjusts when the boost bypass valve opens/closes. Try moving the actuator down and see if you get an increase in boost, if not slide it the other direction.

    I wish I still had my '03 Service manual.... I could have posted the adjustment instructions for ya.

    U.M.
  7. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    Im using fords service manual.same one they used in 03.i will try that later thanks for your input.
  8. Uncle Meat Banned

    Member Since:
    Jun 13, 2002
    Message Count:
    3,869
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Prattville, Alabama
    So are you saying your manual doesn't outline the proper procedure for adjusting the boost bypass actuator?

    U.M.
  9. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    It says the tool comes with a new actuator,has picture of tool on actuator, looks like it clamps onto actuator rod,than u rotate the actuator into position until the rod engages the lever.guess those steps might work.my actuator wiggles,hoses were pulled many times during this.um i also had blower rotors out to clean off black buildup,those rotors were cool very heavy
  10. TheDukeOfEarl New Member

    Member Since:
    Oct 21, 2004
    Message Count:
    128
    Likes Received:
    0
    Trophy Points:
    0
    You removed the coating from the blower rotors?
  11. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    The black i took off looked like baked on oil as like the underside of valvecovers.i had low boost before cleaning .the black came of with just rubbing .
  12. Uncle Meat Banned

    Member Since:
    Jun 13, 2002
    Message Count:
    3,869
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Prattville, Alabama
    With as many miles as you have on that car I would think a blower rebuild/refurbish would defiantly be in order!

    U.M.
  13. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    UM you are most likely right as always. I can make u a copy of my cd if u like .no charge for stangnet .
  14. Uncle Meat Banned

    Member Since:
    Jun 13, 2002
    Message Count:
    3,869
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Prattville, Alabama
    Don't really need it any longer since I sold my snake... You wouldn't happen to have one for a 2009 CTS-V Caddy by chance would you? :p

    U.M.
  15. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    My wife wants ur car.that has the corvette engine with blower?got stick in that thing
  16. Uncle Meat Banned

    Member Since:
    Jun 13, 2002
    Message Count:
    3,869
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Prattville, Alabama
    Yeap, it has the drivetrain from the ZR1 in it. Just detuned a little... down from 638HP to 551HP. :D

    U.M.
  17. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    Ok moved actuator.got boost to go up and down,i will go c if my local dealer can lend me a tool.What do u think about what earl said with coating on rotors?didnt seem to me like it was part of it but i know jack about blowers.the car to me is still not right.it will buck when you nail it,in 4th at 20mph nail it and it studders,no ping heard and it will accelerate any thoughts?when cel lites its 455 and 457 sometimes 453.when checking those i was led to an intermitting problem.457 will stall engine any tie thier
  18. Uncle Meat Banned

    Member Since:
    Jun 13, 2002
    Message Count:
    3,869
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Prattville, Alabama
    The Lightning blowers came with Teflon coated rortors, but I don't believe the Eaton's on the Cobra had any special coating on them. Superchargers and turbos in general have extremely tight tolerances and over time they wear like anything else. Your rotor to case clearance, or rotor to rotor clearance may be excessive due to the age/mileage of your car and this is causing it to not make as much boost as before.

    Now punching the car in 4th gear at 20mph sounds like a recipe for disaster to me! That's WAY too low and puts unnecessary strain on the motor when you lug it like that.


    U.M.
  19. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    Um with the service manual i brought it came with a 2nd disc.it has 46thru93 trucks and all mustang ,all production numbers how many colors ,who had what ect...on cobra it says it uses the same model as lightning .with a cast aluminum case, machined aluminum internal rotors.7.5to8.0psi. I thought the cobra was set at 10?maybe i should try another gauge.how much would you trust a vac/pressure gauge?it use to go to 10 and 12 if done right. Thats on stock gauge and the t in boost is as hi as it goes,it it had numbers t would b 8.i lowered gap on plugs to 35 looking 4 miss,works been slow havent drove it yet.wife is driving it and is to easy on it to feel it.sorry im bored
  20. hotcobra03 Premier Member

    Member Since:
    Jul 25, 2007
    Message Count:
    1,000
    Likes Received:
    1
    Trophy Points:
    38
    Location:
    poteet,tx
    Update um took your advise and closed gap on plugs to .035.that now feels good.did some diy blower repair and i can buy a kit to coat them again .has anyone tryed this. And earl thanks 4 your input

Share This Page