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Why does increasing comp ratio increase horsepower?

Old Sep 14, 2011 | 04:32 PM
  #16  
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CougarJohn
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From: Cupertino
Fellro, typo. I think pressure is force/area, not force x area. Doesn't change your point, though, which is a good one.
By the way, are there any salts here old enought to remember how the old flathead dragsters used to crackle? They were running 13-14:1 compression and they were lousy breathers. There was a lot of pressure at the exhaust valve which had trouble getting out because of the constriction. Hence, pop! So, more exhaust gas must have been getting out because of the higher compression.
Just a good memory that I throw out. I think it may have some bearing on the discussion.
 
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Old Sep 14, 2011 | 04:36 PM
  #17  
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You are correct, Force /Area, keep the relationship. Had it been as I initially typed, area would have to decrease to maintain the same pressure.
 
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