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easy 400WHP
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12,682 Posts
compression ratio?
or compression (in psi) for each cylinder

compression ratio for USDM NX is 9.5:1 JDM is 10:1, I assume youhave a USDM

Compression test should read around ~160 + or - a few across the cylinders,i believe.
 

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now on the West side!
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3,661 Posts
178psi, down to 150psi is acceptable as long as there is no more than a 15% difference between the cylinders.
 

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now on the West side!
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3,661 Posts
125 psi = not good. Was the motor warm, and did you have the TB open?
 

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Off-Topic lurker..
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3,122 Posts
He means did you have the throttle open when you checked the compression. It's best to do a compression test when the motor is warmed up. Before you do the test, make sure you pull the fuel pump fuse to relieve pressure in the fuel system. Pull the fuse while the car is running and wait for it to die. Then check each cylinders compression while someone inside holds the throttle open and cranks the car.
 
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