backdate 76 GC heads to 73-74 GA or GB heads |
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backdate 76 GC heads to 73-74 GA or GB heads |
SuperDave |
Mar 3 2009, 12:09 PM
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#1
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Newbie Group: Members Posts: 5 Joined: 6-January 09 From: Oklahoma City area Member No.: 9,907 Region Association: Southwest Region |
I'm a newbie here. I've tried searching pelican and here to no avail. My apologies if this has been covered before...
I am very close to buying a 76 2.0 to replace the 1.7 in my 72. The 2.0 still has the original heads and emissions equipment. I've read enough to know the emissions equipment made the car run hotter and less efficiently and my state (Oklahoma) doesn't require it so I'm planning on removing the air injection. Three questions: Are 73-74 heads a bolt-on for the GC engine? If so, would I gain anything by replacing my 76 heads with GA/GB heads or should I just fill in the holes like was discussed in a recent thread? I've heard the valve sizes are different between 73-74 and 75-76 heads, but haven't been able to verify this. True or false? Thanks! David |
r_towle |
Mar 3 2009, 02:58 PM
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#2
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Custom Member Group: Members Posts: 24,588 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
No one has explained why some have the head breather ports and some do not...
Any ideas? Rich |
SirAndy |
Mar 3 2009, 03:07 PM
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#3
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Resident German Group: Admin Posts: 41,676 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
No one has explained why some have the head breather ports and some do not... Any ideas? Well, early cars didn't have them, they were added later in the production. My guess would be either they are beneficial to the life cycle of the engine or they are emission related. (IMG:style_emoticons/default/idea.gif) Andy |
SuperDave |
Mar 3 2009, 04:23 PM
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#4
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Newbie Group: Members Posts: 5 Joined: 6-January 09 From: Oklahoma City area Member No.: 9,907 Region Association: Southwest Region |
No one has explained why some have the head breather ports and some do not... Any ideas? Well, early cars didn't have them, they were added later in the production. My guess would be either they are beneficial to the life cycle of the engine or they are emission related. (IMG:style_emoticons/default/idea.gif) Andy Sounds like venting the crankcase and reburning the gases is both helpful on emissions and helps increase longevity: http://en.wikipedia.org/wiki/Positive_Crankcase_Ventilation Seems to me that early cars wouldn't have breather tubes, and later cars would. Am I missing something? I don't have the motor or I'd go look! |
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