1. Hello there guest and Welcome to Fox Body Mustangs forum, This forum is intended to be used by enthusiasts of the Fox body Ford Mustangs (1979-1993)!
    To gain full access you must Register. Registration is free and it takes only a few moments to complete.
    Already a member? Login here then!

    Dismiss Notice

My 90 Mustang lost the Classic burble exhaust Sound At Start Up

Discussion in '1987 -1993 Mustang GT' started by Doug Gia, Dec 26, 2017.

  1. Doug Gia

    Doug Gia New Member

    2
    0
    1
    After I had the engine rebuilt, my mustang runs fine but for some reasons, it's lost it classic loud burble exhaust sound when I start it up. Please advice or any suggestion would be really nice of the members. Thank you.
     
  2. wbrockstar

    wbrockstar Qwik Enuff 4 Me

    12
    4
    3
    Anytime you change something from stock,it can change its sound.Removing something as simple as the factory air intake silencer,behind the airbox,can change the sound. If you had the cylinders bored .030 over for the rebuild,that can change the sound. Anything done that brings in more air or puts out more exhaust can alter its sound. I would,however,check the converters and mufflers to make sure no clogs are present and the internals of the mufflers arent collapsed.
    You can run a cylinder balance test too,to make sure each cylinder is putting out equal amounts of power.

    (Cylinder balance test link)
    http://sbftech.com/index.php/topic,2471.0.html
     
    Last edited: Dec 27, 2017
    Doug Gia likes this.
  3. Doug Gia

    Doug Gia New Member

    2
    0
    1
    Hi Wbrockstar,
    Thank you for the helpful respond. You pointed out a few things here that I did. 1) I removed the factory air intake silencer, 2) As you mentioned about bringing in more air, I also installed a bigger throttle intake, a 65mm versus 55mm from the factory. After a few thousand miles of still quite at start up, I had my Catalytic converter replaced and also put in new Borla Pro XP, but still a very weak exhaust sound at start up. I also have a 1987 Mustang GT that is completely stock and the exhaust burble sound at start up is amazingly loud and deep that always turned people heads at the gas stations. I really miss that sound in my 1990 Mustang. Thanks again Wbrockstar for your respond and great inputs. I will now have to look on E-bay for the factory 55mm intake throttle but at least I still have the air intake silencer.
     
  4. wbrockstar

    wbrockstar Qwik Enuff 4 Me

    12
    4
    3
    If the exhaust sound didnt change until after you done the rebuild, its probably more related to that or the Borla exhaust vs the throttle body you changed.The exhaust having larger diameter pipe or the mufflers??
     

Share This Page