Just did first compression test, results posted
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Joined: Aug 2020
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Just did first compression test, results posted Stock ls2 engine 88k miles, Procharged makes about 600whp
Compression test was done with cold engine, I did it after rethreading 2 cross threaded spark plug holes with a backtap thread repair tool which should of collected most of the metal shavings .
I live at a sea level around 200ft.
212 #8 #7 208
173 #6 #5 210
205 #4 #3 203
194 #2 #1 200
18.4% diff. between #8 and #6
This was my first compression test, I did it cold since I was repairing those holes and changing plugs. Not sure if doing it cold could have caused the difference in results between #8 and #6. I'm about to do a wet compression test on #6 soon to see if there's any difference.
I find these results a bit odd since cylinder #6 and #2 were the ones with the cross threaded holes and have the lowest compression. Maybe it's just a coincidence. Cylinder #2 was cross threaded the longest, and I kept swapping spark plugs despite this, #6 was only cross threaded for one spark plug swap. When I was repairing the hole recently, my tool actually broke inside the hole and I had to use a magnet to fish out the pieces which I can confirm I got them all, Here's a link to my other thread if you want more details on this. The only pieces I wouldn't be able to get out would be the aluminum shavings form the head, but even then I don't think that would cause low compression results this quickly if at all.
Thoughts, suggestions?
Compression test was done with cold engine, I did it after rethreading 2 cross threaded spark plug holes with a backtap thread repair tool which should of collected most of the metal shavings .
I live at a sea level around 200ft.
212 #8 #7 208
173 #6 #5 210
205 #4 #3 203
194 #2 #1 200
18.4% diff. between #8 and #6
This was my first compression test, I did it cold since I was repairing those holes and changing plugs. Not sure if doing it cold could have caused the difference in results between #8 and #6. I'm about to do a wet compression test on #6 soon to see if there's any difference.
I find these results a bit odd since cylinder #6 and #2 were the ones with the cross threaded holes and have the lowest compression. Maybe it's just a coincidence. Cylinder #2 was cross threaded the longest, and I kept swapping spark plugs despite this, #6 was only cross threaded for one spark plug swap. When I was repairing the hole recently, my tool actually broke inside the hole and I had to use a magnet to fish out the pieces which I can confirm I got them all, Here's a link to my other thread if you want more details on this. The only pieces I wouldn't be able to get out would be the aluminum shavings form the head, but even then I don't think that would cause low compression results this quickly if at all.
Thoughts, suggestions?
