Cliff Ruggles' Quadrajet electric choke issues

Discussion in 'The Venerable Q-Jet' started by johnriv67, Feb 16, 2020.

  1. Cliff R

    Cliff R Well-Known Member

    It typically takes several dead cold to fully warm starts working very quickly to find the most ideal settings. Once you do it will be nearly flawless in any weather.

    There is one scenario that jumps in and makes things a little weird and that's if/when I fire mine up in pretty cold weather and back it out of the shop as soon as it goes to curb idle, then shut off the engine.

    Without the engine being well heat soaked the choke will more times than not close the flap and raise the fast idle cam within a few minutes. This can make it difficult to start if I make the mistake of hitting the throttle once or twice, or just as bad it's back on the fast idle again for a minute or so till it drops to curb idle so I can put the trans in gear and get moving again.

    I'd add here that one way to help prevent the potential flooding issue in that scenario is to simply turn the key on and don't start the vehicle right away. Give it just enough time so the coil heats up and the choke flap starts to open a tad. The choke pull-off will move in quickly so you really don't have to wait very long. I very seldom run into that particular problem simply because I don't typically partially warm up the engine then shut it down.

    There are reasons why Holley carbs don't need chokes even for cold weather starting. They are considerably less efficient and by calibration and design a LOT "fatter" at idle and off idle than factory carbs. I still remember WAY back when I ran a Holley 4781-2 DP for a while. I could start the engine in the dead of Winter with half a dozen pumps of the throttle and "feather" it till it warmed up a minute or two then good to go. That carb worked well on my engine but ran no quicker than my q-jet anyplace and consumed considerably more fuel for "normal" driving. Best case scenario I went close to 180 miles a few times before going on fumes, most tanks I'd go around 160 miles. The q-jet doing the same thing will EASILY go 200 miles and often closer to 220-230.....FWIW......Cliff

    PS: forgot to add that the Q-jet has a "fail-safe" built into the design for a flooded condition. If you hold it to the floor it mechanically opens the choke flap to purge the engine so it will fire up. Just back off the throttle quickly when it starts and the choke pull-off comes in and keeps the flap open till the E-choke gets on line again and opens in the rest of the way.....
  2. HotRodRivi

    HotRodRivi Tomahawks sighted overseas

    Hahahaha this reminds me of when I first got my 68 pontiac GP and my start up cold start recipe was pump like mad 10 times and hold it to the floor. Ive been ware you are at in a similar way John. Your working through it quite well.

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