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In my mechanics class last night I changed my plugs(they were in good condition @ 60,000 miles) Anway since I had the plugs out I was curios about doing a compresion test. So we gathered round my car screwed in a psi gauge and I turned the motor over. We did this to each cylinder and the results are in. On three of the cylinders it was 160 psi and the last one was 175( my teacher said that might be due to some carbon build-up and I should get some pour in gas tank fuel injector cleaner to get that broken up). The question at hand is what are the factory specs for compression of a healthy d17a2 motor? IS 160 psi good or bad? Am I close to factory specs or way off? Any help is appreciated thanks.

 
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your specs for compression are 135 PSI for each cylinder with a 28 PSI maximum variation between each cylinder. Its a possibility that you do have some carbon buildup on the piston tops. But use something better then an in tank fuel injector cleaner as all fuel these days are required by law to have fuel injector cleaner in it. Basically fuel is required to have cleaning detergents in it. The fuel injector cleaners are a waiste of money.

Try some top end cleaner, as that should help break up alot of carbon buildup.