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Compression Ratio . . . Power???

  • Thread starter Thread starter nonosstang
  • Start date Start date Apr 5, 2004

nonosstang

Founding Member
Nov 9, 2001
142
0
0
Newark, CA
Apr 5, 2004
#1
  • Apr 5, 2004
  • #1
How much power would you lose by dropping your compression ratio from 10.3:1 down to 9.3:1? Would it be a lot? Say the motor is a 400hp 302.

I'm not looking for a specific number or anything . . . just an idea.
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Apr 5, 2004
#2
  • Apr 5, 2004
  • #2
i heard something from a mopar friend that said 1 point in compression ratio (ie, 9:1 to 10:!) was about 10% of your net power. But I can't say I've seen anything that confirms it, though a little under 10%, somewhere in the 5-8% range, seems to make sense to me.
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Apr 5, 2004
#3
  • Apr 5, 2004
  • #3
doh
 

Max Power

Active Member
Jul 31, 2003
1,774
1
36
St Paul
Apr 5, 2004
#4
  • Apr 5, 2004
  • #4
Saw a test in Hit Rod last year on a mopar 440 that yielded a 4% change for every point in compression.
 
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