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Discussion Starter #1 (Edited)
Could someone post the cylinder dish and combustion chamber volumes for 07 and 08 100 engines so i can determine my exact compression with a simple slug swap..... and so i can determine if it's even worth the time.

Thanks in advance.
 

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Discussion Starter #4
It's not the dish in the piston, but the offset of the wrist pin. When used in an 07 the 08 Pistons net you roughly 10.25:1cr. Just under half a point.
Do you know their position relative to the deck?
 

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think I saw somewhere that milling the base of the cylinders raises compression somewhat.
can't remember where but.
 

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Discussion Starter #6
think I saw somewhere that milling the base of the cylinders raises compression somewhat.
can't remember where but.
Thats true, but depending in the piston height, the quench could be too tight at that point.

Having a tighter quench typically creates more turbulence, thus creating a more efficient burn, which makes more MPG and less potential detonation. If it's to tight though, you risk smacking the head with the piston.
 

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Thats true, but depending in the piston height, the quench could be too tight at that point.

Having a tighter quench typically creates more turbulence, thus creating a more efficient burn, which makes more MPG and less potential detonation. If it's to tight though, you risk smacking the head with the piston.
Decking the base of an 07 cyl .030 gives you a nice tight quench area, and also makes about a half a point of compression.
Had all the math in a notebook on pin to crown, and cc of the popular heads. Unfortunately when I moved from the dealer to my new shop; that notebook disappeared. Fortunately for me I remember the end results of the math in my little head
 

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Discussion Starter #8
Decking the base of an 07 cyl .030 gives you a nice tight quench area, and also makes about a half a point of compression.
Had all the math in a notebook on pin to crown, and cc of the popular heads. Unfortunately when I moved from the dealer to my new shop; that notebook disappeared. Fortunately for me I remember the end results of the math in my little head
So if i use 08 pistons AND deck the jugs, will they hit?
 

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Discussion Starter #10 (Edited)
So with the jugs decked .030", which pistons stick above the deck .010", 07 or 08?

the gasket is .022"?
 

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In the old days a trial assembly with plasticine on top of the piston and turning over by hand would reveal what piston head notching was required for clearance piston to valve.
 

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Discussion Starter #12 (Edited)
In the old days a trial assembly with plasticine on top of the piston and turning over by hand would reveal what piston head notching was required for clearance piston to valve.
We still do that to make sure a cam isn't too big to require valve reliefs.
 

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So with the jugs decked .030", which pistons stick above the deck .010", 07 or 08?

the gasket is .022"?
Found some of my stuff. Hate working off the top of my head. Stock 07 piston against a .030 cut CYL gave me a .008 deck. Stock double head gasket was .027. Compressed height gave me deck of .009 with 106 piston, gasket, and .030 cut. Pretty tight, but no ping with premium. Engine has at least 25,000 hard miles on it. The bowl design leaves a ton of room for the valves
 

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Discussion Starter #14
Found some of my stuff. Hate working off the top of my head. Stock 07 piston against a .030 cut CYL gave me a .008 deck. Stock double head gasket was .027. Compressed height gave me deck of .009 with 106 piston, gasket, and .030 cut. Pretty tight, but no ping with premium. Engine has at least 25,000 hard miles on it. The bowl design leaves a ton of room for the valves
So with 07 pistons and .030" cut cylinders, I'd have a .035 quench?
 

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So with 07 pistons and .030" cut cylinders, I'd have a .035 quench?
Pretty much sums it up. Almost a perfect area. With a good intake, and exhaust the torque curve looks like a pool table
 
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