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MSD or Jacobs?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by chevyboy24598, Jul 23, 2001.

  1. chevyboy24598

    chevyboy24598 1/2 ton status

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  2. 83ZZ502_Jimmy

    83ZZ502_Jimmy 1/2 ton status

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    Go with the MSD 6AL. It's what I use on the ZZ4. I have heard many horror stories about the Jacobs ign's. Make sure you get the upgraded coil to make the most of the new MSD. Sidenote: the 6AL gives you a rev limiter. The 6A does not and cannot be upgraded.

    '83 GMC Jimmy 4x4 ZZ4 Crate Motor
    '83 Chevy K20 Sand Drag Racer, 578 RWHP
    '94 Impala SS
    '01 Chevy 2500HD 4x4 w/8.1L & Allison Auto
     
  3. chevyboy24598

    chevyboy24598 1/2 ton status

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  4. 89Jimmy

    89Jimmy 1/2 ton status

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    I would do anything that I can to steer you away from Jacobs. I bought their box, wires, and coil set. No mpg improvement, ran smoother at idle. The box died in 8 months. I got sick of trying to get it warrentied. Also, the idle improvement was still there after the box was removed, so the coil was the big factor. The people at Jacobs are big on excuses but little else.
    John

    So MUCH to do, So LITTLE cash.
     
  5. 72jim

    72jim 1/2 ton status

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    summit raceing has a good selection of msd stuff and other ignition items too. prices are good and i'm not sure where you are located but i now the local checker store here will match summits prices. helps to get things a lil faster. try jegs too
     
  6. 84_Chevy_K10

    84_Chevy_K10 Banned

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    Unless you're going to exceed 4500 RPM, ANY upgrade to your ignition is a waste of money.

    I too would tell you what a piece of [censored] Jacobs ignition is, but I've never had it. I know that I've NEVER seen a sucess story with it (added in edit) and that I've never seen someone buy it and leave it on very long. I don't even know how they're still in business with the crap they sell.

    MSD is what the pros use. If I was going to upgrade my ignition, I'd do the module, seperate coil, and good wires. The box is nice and adds a rev limiter, but really isn't necessary.

    I suggest that if you're going to go with the box, either get the 6AL or get the Off-Road and put a rev limiter on it.

    What do I have? Stock HEI. My 305 makes 250 HP @ 4500, and that's all the power I need. I don't need to spin it anymore--as the head design is done at 4500, the cam's finished at 5000 even if the engine could breathe, and the 1 1/2" headers and 2 1/4" exhaust are not made for much more RPM either.

    Tim
    '84 Chevy K10, lifted, loud, fast, and 3/4 ton axles<P ID="edit"><FONT class="small">Edited by 84_Chevy_K10 on 07/23/01 07:02 PM.</FONT></P>
     

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