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Discussion Starter · #1 ·
Just playing around with a few numbers...

1. stock rsx-s k20a2
2. stock tsx k24a2
3. k20a2 stroked with s2200 crankshaft, custom rods, 1.50 r/s ratio
4. k24as destroked with s2200 crankshaft, custom rods, 1.72 r/s ratio

This is using a "shelf" 2004+ S2000 crankshaft, for comparison purposes only.

Just wanted to give you guys an idea how much you can stroke a k20a2 (oem 2004+ s2000 crankshaft dependent), and also how little you can destroke a k24a2 (oem 2004+ s2000 crankshaft dependent)

The last pic just shows how much material is between the tsx cylinders.
 

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dam 9.6 c.r with the s2000 in the k24. aftermarket pistons a must for that one, if u r at all serious unless ur going the turbo way
 

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Discussion Starter · #6 ·
Here are the S2000 original and later versions. I couldn't find the exact chamber volume and/or piston cc's. So I used the type-s/tsx head cc's.

duckmanEG: That 9.6 cr is using the same piston but with the shorter (90.7mm) stroke. Yes, you chould use "proper" FI pistons if you are going that route.

Note: notice rod ratios go from 1.82 down to 1.65
 

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Your sure the deck height is 225? How are the rods measured from where to where on the rod? and how do you measure the length of the piston, i take it you measure from where it connects to the rod to the very top? but where top of the pin center of the pin or bottom?

For instance if i wanted to put a s22 crank in a k20 with the s22 rods, i would need to find a piston that is 13mm shorter than the s22 piston? according to deck heights? 225-212

Are all honda pistons the same length and vary due to compression?

And isnt weight a factor when mixing and matching pistons and rods to crankshafts? Arn't crankshaft counterweights balanced determined to the weight and length of the piston/rod? For instance taking weight from crankshaft counterweight throw off the balance completely?
 

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Discussion Starter · #8 ·
I found the deck height somewhere on the net, the rod lengths are exact, but I am not sure on the piston dome cc's nor the chamber cc's. Rods are usually measured c to c (center to center), I took an educated guess on the piston height, which works out to be deck height (which I found) minus 1/2 stroke minus rod length (which I found) minus piston height. You wouldn't "find" a piston that is 13mm shorter, but a rod that is about 13mm shorter, which in this case would be approximately 136.6 mm.
 

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Discussion Starter · #10 ·
compression height is top of the quench area (piston flat) of the piston distance to the center of the wrist pin. The chart basically calculates compression, but it has other neat figures.
 

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compression height is the measurement from the center of the wrist pin to the top surface of the piston? What is quench and where do you get that chart from?
 

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What about head differences ive been having the hardest time finding the difference between the s22 head and the k20aR head, i have some pictures of the s22 head ports and valves let me see if i can find them.
 

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Discussion Starter · #18 ·
Now that I am sober...

compression height of a piston is the distance from center of piston pin to the top of the piston

quench is the distance between the piston top and the head, calculated by adding deck height clearance and gasket thickness.

What head differences are you looking for between the two?

The rod widths on Crower's chart are "manufactured", and not necessary the oem specs. But I use the chart as a reference.
 

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Like for port size pictures between the two, head differences.

Mainly what all makes it 240 instead 220hp. Where does that extra 20 come from? im thinking mainly stroke difference but i want to see if there are differences in the way the made the head. the pictures i have of are a ported s22 head, so no good.

The original s2 had 240 and the new s22 moved the power down the rpm and added torqe. 162ft is not bad. so if a regular 2.0 made 240 im trying to do the same.
 

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Discussion Starter · #20 ·
The intake valves are 36mm on the s2000 vs 35mm for the type s. I am not sure of the exhausts, maybe 31mm considering the type s's are 30mm.
 
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