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Old Jul 21, 2009 | 06:40 PM
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hello, can someone tell me how many degrees of centrifigal advance is built into a stock Hei? i just bought a new hei from summit and i am trying to figure what to set my initial timing at to ensure a total of 36 degrees without vac advance hooked up. thanks
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Old Jul 21, 2009 | 09:48 PM
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Several ways to go about it.

1) Was there any technical information in the box when you got it?

2) Call Summit's tech line and ask for some information on the distributor.

3) Put a timing tape on your harmonic damper, install the distributor, and run the engine up to the RPM needed to max out the centrifigal advance, adjust to 36 degrees, and then check to see that your idle timing is reasonable. Be sure to hook the vacuum advance up when you're done.
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Old Jul 21, 2009 | 11:40 PM
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I think the timing tape suggestion is right on. Plot your timing curve, both centrifugal and vacuum. Then you know...
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Old Jul 22, 2009 | 12:29 AM
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Factory HEI's have 20 degrees mechanical.
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Old Jul 22, 2009 | 01:34 AM
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ok. im confused!! i took a look under cap and there is no advance stop bushings like in an msd. without being able to set the centrifigal advance how do i now where to set initial? summit tech said that the springs and rpm combo determine total timing? sounds weird to me but the hei advance kit they sent with it showed only spring changes and nothing to do with bushings. either way the earliest i can be all in is 5000 rpm and that is with there light springs. are you as confused as i am? help
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Old Jul 22, 2009 | 05:10 AM
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I'm running a Summit, just set the did this,, i set the timing to 12°, per factory spec for a 4 sp, was all in at 34-36° at 2500 rpms.
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Old Jul 22, 2009 | 04:16 PM
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I took a quick look at those summit blueprinted distributors. Summit says they come with medium weights. I noticed that the weights that come with some mechanical advance spring kits are much smaller than the factory originals. I think you need heavier weights in that distributor, or, try just using one spring.
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