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Weird Head Numbers?

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Old Nov 20, 2004 | 11:03 PM
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Default Weird Head Numbers?

Well guys I had a suspision that the motor had work done on my 76 L48 and I pulled the valve covers to find a set of 3986339 heads. Now I was wondering if anyone has any info on these all I know is that they are 74cc and they were used on 307 and 350 in 71. Can anyone help me and are these heads upgradable.

Thanks
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Old Nov 21, 2004 | 08:00 AM
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bump
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Old Nov 21, 2004 | 08:04 AM
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If I'm not mistaking those heads sport tiny 1,72 intake valves and they came on trucks too. They are a typical POS open chamber smog head, time to get some decent stuff. They do make nice paperweights or fireplace ornaments
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Old Nov 21, 2004 | 08:42 AM
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Originally Posted by hirevroller
Can anyone help me and are these heads upgradable.Thanks
Sure there upgradeable. Throw them out and get new ones. They are not very good heads.
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Old Nov 21, 2004 | 09:51 AM
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Awh Crap i was affraid of that. OK thanks
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Old Nov 21, 2004 | 10:09 AM
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Here it is in black and white: http://www.chevytech.net/3c3986339.html
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Old Nov 21, 2004 | 10:19 AM
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Awesome page, that one is good for a bookmark
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Old Nov 21, 2004 | 10:22 AM
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Yeah, when I found that site the other day I scoured nearly every page. Amazing amount of info in there!!!
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