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Gmc engine tune


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Hi All


Trying to get my GMC 353 ready for the road after a rebuild, manuals say set the timing at 5degrees btdc is this ok with todays fuel, also one manual says 12 thou for in and ex tappets another says 12thou in and16 thou exhaust any of you gmc chaps found out which is right



Regards all Warrior :(

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There were THREE exhaust valve settings. Originally it was .012 for intake and exhaust.


It was increased to .016 for 'early camshafts' and .020 for 'late camshafts'.


How can you tell if you have an early or late cam?


Here is the TM goodness:



Edited by deadline
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