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Combustion Ratio Calculator??

  • Thread starter Thread starter nito88stang
  • Start date Start date Sep 10, 2004

nito88stang

Founding Member
May 23, 2002
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Fullerton, California
Sep 10, 2004
#1
  • Sep 10, 2004
  • #1
Can someone point me towards a combustion ratio calculator or tell me what exactly my ratio will be with my new combo?

I have SpeedPro pistons that give 9:1 CR with 58 CC heads. I have however the TrickFlow TW heads with 61CC's. So i know i am below 9:1 and probably around 8:7 or 8:8 but wanna know exactly (this is gonna have a blower bolted on later)

thx alot
 

giddyup306

Founding Member
Oct 22, 2002
3,041
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59
Sep 10, 2004
#2
  • Sep 10, 2004
  • #2
Somewhere around 8.8:1. Don't know the formula off the top of my head but I'll try and dig it up.
 

giddyup306

Founding Member
Oct 22, 2002
3,041
2
59
Sep 10, 2004
#3
  • Sep 10, 2004
  • #3
one cylinder swept volume + deck cc + head cc

deck cc + head cc

Example: 545 + 3.378 + 48 = 596.378

3.378 + 48 = 51.378 = 11.6:1
 

jrichker

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Sep 10, 2004
#4
  • Sep 10, 2004
  • #4
See http://users.erols.com/srweiss/ for all kinds of automotive calculators.
 
T

tjm73

Founding Member
Aug 3, 2000
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Rush, NY
Sep 10, 2004
#5
  • Sep 10, 2004
  • #5
giddyup306 said:
one cylinder swept volume + deck cc + head cc

deck cc + head cc

Example: 545 + 3.378 + 48 = 596.378

3.378 + 48 = 51.378 = 11.6:1
Click to expand...


HUH!?!?! This makes no sense to me by its self or in relation to the post prior to it.
 
T

tjm73

Founding Member
Aug 3, 2000
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48
Rush, NY
Sep 10, 2004
#6
  • Sep 10, 2004
  • #6
This is a good one too.

http://www.prestage.com/community/C...tors/Calculate+Compression+Ratio/default.aspx

1 cc in head volume is worth about .12 in compression on a 302.
 

giddyup306

Founding Member
Oct 22, 2002
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Sep 10, 2004
#7
  • Sep 10, 2004
  • #7
tjm73 said:
HUH!?!?! This makes no sense to me by its self or in relation to the post prior to it.
Click to expand...


It's the formula to calculate compression ratio.
 

tomst9

Founding Member
Jun 17, 2002
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Bethlehem Pa
Sep 10, 2004
#8
  • Sep 10, 2004
  • #8
Whats the deck hieght or cc of a stock 5.0l motor?
 

nito88stang

Founding Member
May 23, 2002
2,012
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Fullerton, California
Sep 10, 2004
#9
  • Sep 10, 2004
  • #9
Thx for all the info guys, but i dunno wtf to plug into the formula. Although if what tjm73 said is true, then i'll be at 8.76:1 CR.
 
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