Discussion in 'Holley' started by 71stagegs, Nov 25, 2017.

  1. 71stagegs

    71stagegs bpg member #1417

    Whats good AFR for a 464 11-1 comp TA ported heads 235-242 519 lift cam ta intake 1000 cfm AED headers.I got the carb with 84-92 was way to rich now 80 pri 88 sec cruise is 13-5- 13.8 WOT was 11-7 i'm down to 88's still only 12.2 going to try 86's see what that does what's a good number to shoot for thx Steve
  2. hugger

    hugger Well-Known Member

    What are your plugs telling you?
  3. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    I would shoot for 12.5:1 to no more than 13:1 WOT to make sure you're not running lean. You need to factor the weather, time of year and temperature when you're checking the A/F ratio as well. The winter formula gasoline is different than the summer formula gasoline so be aware of that too.

    With a carb the ratios will change with the weather and the gas formula so you may need to adjust for the summer formula?

    For cruise I like between 14:1 to 15.5:1 with light load, and idle around 13 to 13.3:1 so its not to lean at the end of the quarter mile when the foot is off the go and smashing the stop peddle(basically the same for a quick street brake stomp too).

    If you're going to run closer to the lean end of the scale, make for dam sure that the tune is good meaning no detonating or pre-igniting. GL
    Last edited: Nov 25, 2017
  4. Bens99gtp

    Bens99gtp Well-Known Member

    The pic of those plugs is richer than 2 jet sizes will change. Are the getting dirty at idle or when running wide open..........if rich at idle the plugs may dirty up enough that 1 pull at wot might not clean them up.

    I ran a 1000 cfm prosystems carb with 84/92 and a 3.5 pv on my 464,11.5, ported iron heads, had cams from .500 to .600 lift never really had to jet it much for cam changes. Had a customers stk aed 1000 on it once it ran withing a few hundredths.

    When I tried to down jet to 80/88 my car wouldn't even make a 1/8th mile pass b4 it laid over from being too lean.

    Is this a new carb? Wonder if something is in one of the air bleed circuits causing a restrictions and an over rich condition.

    My car was also had a 4500 converter and 4.1 gears so that could have a different effect on it too

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