Just did a compression test on my freshy rebuilt gsr motor
160-155-170-165
this is on a gsr block b16 head with wiesco 9.1 pistons with 100 miles on it.
I dont know what to think, maybe its the crappy discount auto tester because sometimes it would fluctuate up or down 5%
And yes I did it WOT with the injectors and the fuse pulled...
Is this good or bad, could it be cause the rings havent fully seated yet?
another thing I noticed was air is pushing out the breather, theres no smoke but I thought the breather sucks in air?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HighRevn &raquo;</TD></TR><TR><TD CLASS="quote">
Is this good or bad, could it be cause the rings havent fully seated yet?
</TD></TR></TABLE>

Nothing is official since you only have 100 miles. Drive it hard for another 500 and then do the test again. whatever method you use be extremely consistant. If you crank it over 5 times then do that for every cylinder.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HighRevn &raquo;</TD></TR><TR><TD CLASS="quote">
another thing I noticed was air is pushing out the breather, theres no smoke but I thought the breather sucks in air?
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A breather is attached to the valve cover....when you get gases that "blow by" the rings they come out there through a long process. It's totally normal and is even worse on a built engine. My car does it hard-core on the dyno with 26PSI

 

engine warm?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by adseguy &raquo;</TD></TR><TR><TD CLASS="quote">

Nothing is official since you only have 100 miles. Drive it hard for another 500 and then do the test again. whatever method you use be extremely consistant. If you crank it over 5 times then do that for every cylinder.

A breather is attached to the valve cover....when you get gases that "blow by" the rings they come out there through a long process. It's totally normal and is even worse on a built engine. My car does it hard-core on the dyno with 26PSI</TD></TR></TABLE>
wow thats good to hear, I going to the dyno next saturday, so is that normal with a new motor with so little miles on it?

 

and yes it was done at normal operation temp

 

anybody else

 

valves adjustment? May need to readjust after everything breaks in...
Is it using any oil?

 

just did a adjustment, not eating any oil

 

Check it again after the dyno. It should be a little more even by then.

 

before i went to the dyno
i could only get 160psi with my lsvtec 9:1

after i got it tune
now its at 180

 

Keep a log of your compression test results. And try to always conduct the test the same each time. I found that my compression numbers still rose until the 750~1,000 mile mark.

 

thanks guys, I appreciate it