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Old 12-15-2009, 04:30 PM   #1
BluTrukker's Avatar
Join Date: Mar 2008
Location: Stewartville, MN
Posts: 440
HEI question

I have 2 used HEI's that I can to upgrade my truck. I am not all that familiar with them, and need some advice. They are both out of mid 80's trucks. One is off a big block and one off a small block. I haven't closely inspected either one yet, they are laying on a shelf at my buddies place and he told me I can have whatever one I want. One has a vacuum advance and one doesn't. Whats the deal with that? I thought all the older stuff had vacuum advance? Is there a benefit to using one over the other? I am putting it on a 307, so I'm only looking for reliable cruising not power.
Trying to save someone from their own stupidity is like teaching a pig to dance. It is a waste of your time, and it annoys the pig!

Last edited by BluTrukker; 12-15-2009 at 04:31 PM.
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Old 12-15-2009, 04:57 PM   #2
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Join Date: Jul 2007
Location: Centrally located between Houston, Austin and Waco. BCS area.
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Re: HEI question

I'd get the one with the vacuum advance. If you're not familiar with the HEI there is tons of stuff on the net to help you. Also, educate yourself on what the mechanical and vacuum advance does and how it's adjusted.

Here's a good site that you can look at but there are others just as good or better:
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Old 12-15-2009, 05:05 PM   #3
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Join Date: Dec 2004
Location: Sierra Vista, Arizona
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Re: HEI question

Replace the vacuum advance with one that is an adjustable VA, makes a big difference.

71 C10 283/3SPD Full Resto
71 GMC 1500 Sierra Grande
70 C10 Suburban Former military GSA truck.
72 Chevy Blazer 4X4, Sloppy Jo, Mountain Climber...Wife says no more trucks.
72 GMC 1 Ton Motor Home, wife said no more trucks until she saw this one.....Gen 3 6.0/4L80E 4.10
68 GMC Suburban was 3/4 ton, now 1/2....Wife shook her head...
71 C30 Wrecker....
72 GMC C2500 Blue Beard....Its a Builder
71 C20 Scott-Bilt As weird as it gets..BB Cheyenne AC Truck
68 GMC Long Stepside....They keep following me home...
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