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Compression test

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Old 03-21-2012, 10:34 PM
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car_slave
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Default Compression test

What's your maximum compression psi? I adjusted my 968 valve timing and it went from 175 to 195psi
Old 03-22-2012, 07:25 AM
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Deano968
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Mine average at 200 across the 4, lowest is 195. 65,000 miles when I had it checked.
Old 03-22-2012, 11:19 AM
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RajDatta
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As long as the compression is consistant across all 4 cylinders, that is what matters most.
Old 03-22-2012, 05:56 PM
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Deano968
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Actually I lied! I just dug out my paperwork and it reads...

1 = 205psi
2 = 205psi
3 = 210psi
4 = 205psi

How consistent are we talking out of interest?
Old 03-22-2012, 08:54 PM
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car_slave
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This is good info. I'm actually trying to see how close my valve timing is to spec. I never really did a proper job of setting it after doing my cam chain and guide job. I may still have some more adjusting do because I'm at the limit of the cam wheel adjuster.
Old 03-23-2012, 01:42 PM
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Cloud9...68
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Originally Posted by car_slave
This is good info. I'm actually trying to see how close my valve timing is to spec. I never really did a proper job of setting it after doing my cam chain and guide job. I may still have some more adjusting do because I'm at the limit of the cam wheel adjuster.
Hmmm... That doesn't sound right. I just adjusted my cam timing as part of my rebuild, and the cam woodruff key ended up fairly close to the middle of the adjustment range. How did you identify the top of the piston travel (I used a degree wheel I attached to the front of the crank, and a pointer I fabricated and attached to one of the belt guide bolts, in conjunction with a dial indicator)? And of course you did pressurize the variocam, right? IM me if you'd like to talk this over.
Old 03-23-2012, 07:36 PM
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car_slave
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I did my re-install based on original markings. TDC with dial indicator and then lined up on the marks. I got tired of trying to line up cam degrees on the dial indicator, so I just set to the original markings (wear marks). I may take it back apart and set things up properly at a later next week.

The cam markings are made by hand, so yours may be different than mine.



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