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Downsizing Combustion Chambers ?

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Old Aug 24, 2018 | 03:09 PM
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Downsizing Combustion Chambers ?

92' 351W with stock heads and 64cc chambers, what would be the difference in static compression ratio going from 64 > 60 and/or 64 > 58cc chambers.
I'm trying to decide between Promaxx with 180cc runners and 60cc chambers or Windsor Jr with 180cc runners and 58cc chambers..
I had a 350SBC in a 4x4 with Dart 180s and it was a torque monster so i am not hesitant to put 180s on my 351.
Upgrading camshaft and want to take advantage of increased duration by increasing static compression to optimize cylinder pressures.
 
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Old Aug 24, 2018 | 04:55 PM
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https://www.summitracing.com/newsand...ion-calculator
 
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Old Aug 24, 2018 | 06:16 PM
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Thanks but the engine is assembled and installed and in running condition, i don't access to those variables but if i did i would have googled compression ratio calculator
 
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Old Aug 25, 2018 | 01:33 AM
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Plug in numbers you think are close to what you have. Then change the combustion chamber size to see what effect it has. Closer than a guess from a 3rd party. Serving suggestion.
 
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Old Aug 25, 2018 | 06:58 PM
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6 ccs would be about a half point at best.
 
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Old Aug 25, 2018 | 09:50 PM
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Thank-You baddad457, i will go with 58's..
 
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Old Aug 26, 2018 | 09:56 AM
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I did the math(roughly, not knowing the exact numbers) bouncing around going down US287 yesterday (wife driving) and the difference was around a half point on a 351
 
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