Calculate my engine compression please!
#1
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Hey guy'z!
after the LS7 427 , LSX 441 I built for my T/A
I've decided to build a smaller engine , An engine with can be street used and street race with it... H/C ls1 with 400 shot![MAD](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_mad.gif)
I'm confusied with my engine compression and as you guy's have the excess experience of some points that I'm not sure of , please help me with this.
59cc Patriot heads. stg 2 ls6
forged 347 , stock ls1 crank , 6.200 rods , -2cc flat top 3.905 diamond pistons.
0.0041 cometic head gaskets
111 lsa cam < wonderin' if that was needed
notice: when assembling my engine , I polished my block's "on the heads place surface. So a very thin layer was gone out.
How much will my compression be ? I wish it's around 11.7
extra question
how can I increase it until 12 ?
Thanks!
after the LS7 427 , LSX 441 I built for my T/A
I've decided to build a smaller engine , An engine with can be street used and street race with it... H/C ls1 with 400 shot
![MAD](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_mad.gif)
I'm confusied with my engine compression and as you guy's have the excess experience of some points that I'm not sure of , please help me with this.
59cc Patriot heads. stg 2 ls6
forged 347 , stock ls1 crank , 6.200 rods , -2cc flat top 3.905 diamond pistons.
0.0041 cometic head gaskets
111 lsa cam < wonderin' if that was needed
notice: when assembling my engine , I polished my block's "on the heads place surface. So a very thin layer was gone out.
How much will my compression be ? I wish it's around 11.7
extra question
how can I increase it until 12 ?
Thanks!
#3
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To do this right !
Cylinder Diameter
Cylinder Diameter
Cylinder diameter
Stroke ( not rod size )
Head cc
gasket thickness (think you have few to many zeros
piston cc ( flat top , dome , reverse dome cc)
Deck height ( if the piston at tdc is in or out of the whole !
Some will even use gasket bore size!
To get more compression
Thinner Gasket
Deck the heads to reduce cc !
Ummm you can have the block deck to have piston come out .005 or so !
Crank shaft stroke !
But what you have know its really hard to tell you where you are !
Cylinder Diameter
Cylinder Diameter
Cylinder diameter
Stroke ( not rod size )
Head cc
gasket thickness (think you have few to many zeros
piston cc ( flat top , dome , reverse dome cc)
Deck height ( if the piston at tdc is in or out of the whole !
Some will even use gasket bore size!
To get more compression
Thinner Gasket
Deck the heads to reduce cc !
Ummm you can have the block deck to have piston come out .005 or so !
Crank shaft stroke !
But what you have know its really hard to tell you where you are !
![Google](https://ls1tech.com/forums/images/smilies/google.gif)
#4
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Not 100 % but 11.6 would be a close guess!
Changing to .030 would get you almost 12
But if you are 11.6 you are not get see much benifet from a 200 dollar set of gaskets and not sure they even make them for your bore !
Changing to .030 would get you almost 12
But if you are 11.6 you are not get see much benifet from a 200 dollar set of gaskets and not sure they even make them for your bore !
#7
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You need to provide us with more data.
Go to this URL and fill in the blanks with data: http://www.kb-silvolite.com/calc.php?action=comp
Stop guessing and get the data.
Also, don't make your head gasket any thinner until you know the piston's deck height.
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