Step up springs

Discussion in 'Technical' started by wolfheads, Apr 11, 2016.

  1. wolfheads

    wolfheads MadMav

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    I'm running an Edelbrock 600 on my 302(stock) and get several different answers on my question: I checked the vacuum and it shows around 14in. The metering springs are stock that came with the carb. (orange). Do I need to change the springs to the springs that has 7in? I was told that the metering springs should be apx half of what the vacuum reading is.

    Thanks
     
    wolfheads, Apr 11, 2016
    #1
  2. 71gold

    71gold Frank Cooper Supporting Member

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    14" sounds a little low to me....I'm thinking should be 17-19"...:yup:
     
    71gold, Apr 12, 2016
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  3. groberts101

    groberts101 Member

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    I would surely agree with that. Base timing is likely too low and the vac advance mechanism is also probably running off a ported vacuum source which helps nothing at idle speeds. Would be best to check the diaphragm is not leaking and plug it into the full manifold source so it contributes additional spark lead at idle.

    PS. this will also help with gas mileage as well. Get it closer to that 19" mark that Frank posted above and it could be considerably better. Easily 2 mpg or more.
     
    Last edited: Apr 12, 2016
    groberts101, Apr 12, 2016
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    71gold likes this.

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