High RPM at highway speeds

Discussion in 'Engine Topic' started by Sunny Z/28, Nov 15, 2020.

  1. COPO

    COPO Veteran Member Lifetime Gold Member

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    G72Zed, that plug looks awesome.
     
  2. ChevyReb

    ChevyReb Veteran Member Lifetime Gold Member

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    I 2nd COPO on that!
     
  3. G72Zed

    G72Zed Veteran Member

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    Thanks guys, I like those plugs, they have really performed well for me and in many many customers cars that I have built & tuned over the last few years.
     
  4. mrluckies

    mrluckies Veteran Member Lifetime Gold Member

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    Biker is correct, I use vacuum advance hooked up to manifold vacuum, not ported vacuum. One thing I can’t stress enough however is to actually verify your timing mark! I did this on my engine after I couldn’t get it running right and found my mark was off by 10 deg! Granted I have an aftermarket damper that is smaller in diameter than stock and a different aftermarket timing tab. I pulled all of the plugs and put a piston stop in the number one cylinder and then used a socket on the damper bolt to rotate the engine clockwise and mark the damper and then counter clockwise and mark the damper again. Find the halfway point between the two marks and that’s top dead center. Once I did that, I readjusted the timing. It runs stronger, cooler and doesn’t stall in panic stops.

    I have 18 initial and 8 deg vacuum. I started with 10 deg vacuum and needed to back off to 8 on hot days.

    I also went around the four corner idle screws a bunch of times to get it right.
     
  5. sandlapper

    sandlapper Veteran Member

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    ^^^^ THIS ^^^^ agreed! and suggest verifying true TDC on damper should be first step; followed by scribing a line from verified zero-groove on damper thru to center of damper hub. Highlight that line and periodically reference an unbroken line; confirming if damper has or has not slipped.
    :bowtie:
     
  6. 70-camaro

    70-camaro Veteran Member

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    Any progress this weekend?
     

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