Q-Jet part throttle lean condition

Discussion in 'The Venerable Q-Jet' started by CJay, Sep 24, 2017.

  1. HotRodRivi

    HotRodRivi Tomahawks sighted overseas

    Ware is that MEAT FARMS. ? Anything good to bbq in there?
    You can send me any 4 barrel Rochesters I will iron them out !!!
    I find anything 4MV from a Pontiac works better than most factory carbs. I have never tried a chevy style on a Buick yet though. I think the absolute best Rochester came on the SD 455 pontiac firebird.
     
  2. Brett Slater

    Brett Slater Super Moderator Staff Member

    What did you determine was the issue? The secondaries not opening up all the way?
     
  3. CJay

    CJay Supercar owner Staff Member

    Yep! The carb wasn't opening up fully when you floored the car. The secondaries were hardly opening. It was literally a 30 second fix- throw Jen behind the wheel, have her floor the pedal, go under the hood and bend a tang on the side of the Q-Jet till the secondary throttle blades were nearly vertical. It was like I put in a different engine

    I know I keep talking about that LM-2, but that is the best toy I ever bought! Love that thing! There was a bit of a learning curve with it, but after got comfortable with it, I was able to use it zero in all my Q-Jets. Believe it or not, the biggest gains were achieved with the Aquamist car. For some reason I was never able to get that carb adjusted right with just using a vacuum gauge. I finally got that carb straightened out and it literally transformed the way it runs. Runs way smoother now, starts up easier, its got more power. After 15 years, I finally got the car running good

    As far as the beater, the damn thing runs like a top now. its got a 13.8 AFR at cruise. It idles great and the timing and curve is right on. I must of been under that hood every 3 days turning screws, adjusting the timing, and swapping advance springs. Pretty sure I got the combo nailed down on that one. Not even sure now what the fix was for the original issue, but the beater is tuned to the razors edge now!
     
    Brett Slater likes this.

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