i have 1400 mi on my new longblock provided under warranty due to oil consumption problem. i'm going fi soon, so i took my z in for these tests. dealer said everything is fine, but i want you guys to interpret the numbers for me:
dry: 1-185 psi, 2-180, 3-180, 4-185, 5-180, 6-180
wet: 1-205, 2-205, 3-200, 4-200, 5-200, 6-205

btw, on my first engine, i followed the breakin schedule to the letter. this time, i used the heat cycle method and went to redline each time.

 

Numbers look dead on perfect for the stock compression of the motor. Dry test is a regular compression test. Wet test is if they put a little oil in the cylinder to seal the rings....gives higher numbers.

 

really? cool! so much for the factory breakin schedule.

 

Is the heat cycle method the same as the "secret" moto-man (or something like that) break in method that's been discussed in the past to load and seal the rings?

 

don't know about secret. its something i think raceboy posted on the topic of breakin long ago. heat the engine up with gradually more vigorous drives, then let it cool down completely after each drive.

 

Compression test looks good.

 

Perfect if you ask me. Mine compression testing at 190-192 between all cylinders....warm motor, dry. Anything between 180-195psi is excellent, as long as there are not major variances between the cylinders.

 

yes it is the moto-man theory but it isnt his theory alone. Most people who want max hp out of their engines go by this method.

 

nissan figures for this test is 185-140psi. so looks like your golden!!

 

awesome. thanx!