compression ratio info?

[Dartgame]

Finally working on figuring out the compression ration for the 230 I'm building. I have two heads, one is from a (unknown year) 230 and the other is from a '53 218. I have a buret, and measured the cc's on each. Keep in mind that the 230 head appears to have been milled a fair amount, and the 218 not much if any at all.

 

The 230 head CC'd at 74.3 

 

The 218 head CC'd at 82.0

 

My plan is to mill the 218 head. Reason being is that the 230 head is in absolutely atrocious condition, very rusty inside the water passages...awful.

 

My question is about head gasket cc's. I had read that for the 25 inch motors the cc for the gasket is around 18.5 cc. I have not been able to locate info about the 23 inch motors gasket cc's, fel pro has no info. Would it make sense to think that the gasket cc's are similar or the same ?

[Bob Riding]

I did a search for thinner head gaskets a few years ago. Fel Pro and all of the eBay sellers who responded listed their head gaskets for the 23" head at between 0.079 and 0.081 inches thick. I was looking for 0.07 or less to increase compression. Never found one that thin, so I went with a stock copper sandwich gasket.

[Sniper]

Best gasket shows .052" compressed for the 523C gasket

 

https://bestgasket.com/head-gasket-bore-thickness/

[Dartgame]

Thanks guys, Bests info is interesting. Maybe what I'll do is measure the cc's of an old copper gasket I have. I dont want to mess up the new fel pro I intend to use. I would imagine the fel pro being around .80 will compress similar to the best which gives about .052 installed, and .080 new. I'll report findings once I get them, probably in the next week.