# 64 cylider head questions



## remy30006 (Jul 7, 2013)

Can anybody tell me what the difference is between the 9770716 and the 9773345 heads? They both seem to have the same size valves.


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## InjunRAIV (Aug 21, 2013)

9773345
-9770716
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0002629

I'm here all week!

:seeya


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## remy30006 (Jul 7, 2013)

guess I had that coming


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## FNG69 (Nov 15, 2009)

-9770716 were the GTO heads
The 9773345 heads were used in both big car 389 applications and the 2 bbl 326. The advertised cr was 10.5 and 8.6 respectively.


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## remy30006 (Jul 7, 2013)

CR is the chamber size? Is that the only difference? 
Thank you!


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