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Discussion Starter #1
Hi guys- I recently bought an endoscopic camera to connect to my iPhone. I wanted to get a view of my piston tops to see if I could surmise what the previous owner had dropped in. Snaked the camera through spark plug hole and pictures are from #1 and #6 chambers. The motor is a 1964 421 with the 77 heads. The motor seems to run fine on 92 octane. So I have two questions, (1) do these pistons look stock, or are they dished a bit to drop my cr (and why I seem to have no isssue with 92). And (2) the #1 piston looks a bit discolored at top - is that normal or sign of pinging danger? I have never heard this motor ping, although it is free flowing exhaust that is pretty loud. Thoughts appreciated, thank u.
 

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Not factory and it appears they are dished pistons to lower compression. Top of the piston looks normal as you will get carbon deposit on the tops - they do not stay shiny like new for very long.
 

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Discussion Starter #3
Thanks for confirming Jim. I continue to be impressed with po decisions. He had passed away so did not get to talk about the car...
 

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What Jim said. Custom dished pistons. Lucky you. Whoever built that engine built it to live on today's gas. Win-win for you!!!
 
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