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This question is only for people who actually know and not for those who think they do, I have a chevy 350 from a 71 monte carlo in my regal and I want to know if anyone knows what compression this motor has. It has a 2bbl and HEI ignition. Thanks. :biggrin: Eric
 

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Triple OG
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Originally posted by 85REGAL@Sep 7 2005, 09:55 PM~3773642
This question is only for people who actually know and not for those who think they do,  I have a chevy 350 from a 71 monte carlo in my regal and I want to know if anyone knows what compression this motor has.  It has a 2bbl and HEI ignition.  Thanks.  :biggrin: Eric


a compression gauge would...


na, for real its gonna vary man. climate even effects it. Just get a compression gauge and test it so you know what you got.
 

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Originally posted by concrete@Sep 8 2005, 09:18 AM~3775086
a compression gauge would...
na, for real its gonna vary man. climate even effects it. Just get a compression gauge and test it so you know what you got.
actually no it won't

He's talking compression ratio, not the psi number on the compression gauge. The ratio will not change unless you change bore size, piston size, head gasket thickness or heads.


Nobody here is going to know that off the top of thier head. You need to do some google searching to find out. My best guess would be 9.5 to 10.5 :1 It wasn't really a sports car so i wouldn't expect 11:1 or anything like that. Being pre-unleaded fuel though means it shouldn't be any lower then 9 or 9.5:1

Also, JFYI that engine did not come with HEI from the factory, it was retrofitted.

Your best bet is to get the block numbers off the FRONT near the passenger side head on the flat surface that is where the head bolts to.
 

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Triple OG
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yea, I re-read the question...I read it wrong.

if you could tell me the head volume I could tell you what it is...
 

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If I remember right, the comp. ratio on a 2 bbl 350 could be either 8.75 or 9.25.
If it had a 4 bbl, it could be anywhere from 9-10. In 1972, the gas crunch started and the ratios went way down to anywhere from 7.75-8.75 to try and save gas. Any of the repair manuals should have this info so if you have one for a monte, it should say. Mine is at my work so I can't check it right now but I should be fairly accurate. And joe is right, hei is not stock on that engine.
 
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