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Help with compression.

  • Thread starter Thread starter 98gtblue
  • Start date Start date May 2, 2006

98gtblue

New Member
Dec 15, 2003
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houston
May 2, 2006
#1
  • May 2, 2006
  • #1
Help with compression and oil blow by

Anyone know what the compression suppose to be for a 98 GT? My car has 111k miles and I have noticed oil stains from the driver side valve cover where the hose from the CAI to the valve cover connect. Also I notice some oil in my intake tube. Seems like it is sucking in oil. I took the tube off and put a breather filter so it won't get into the intake but looks like the air breather has oil too. I want to do a compression test to see if it is blown piston rings or valve seals. Or what do you guys think it is? Thank you .
 

sgarlic

Founding Member
Apr 21, 2001
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56
May 2, 2006
#2
  • May 2, 2006
  • #2
I'm not sure of the exact compression figure, but usually you check them all, and as long as the lowest one is at least 75% of the highest one, it's considered within specs.
 

DropTopPony

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Founding Member
Aug 13, 2002
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south jersey
May 2, 2006
#3
  • May 2, 2006
  • #3
Its @ 9.3 on your 98..or it should be atleast.
 

sgarlic

Founding Member
Apr 21, 2001
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56
May 2, 2006
#4
  • May 2, 2006
  • #4
He's asking for cylinder compression numbers I believe, not the compression ratio.
 

DropTopPony

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98gtblue

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Dec 15, 2003
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houston
May 2, 2006
#6
  • May 2, 2006
  • #6
Yes, I was wondering compression numbers like 140, 130, 135...etc. Thanks so far for input though. Doing the test this week. For 111k what is better new engine or just swap the heads? I know something is wrong though because oil is suppose to stay in the engine not outside.
 

DropTopPony

Noob Slayer
Founding Member
Aug 13, 2002
2,570
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south jersey
May 2, 2006
#7
  • May 2, 2006
  • #7
sounds like a cracked ring(s)...maybe a new shortblock.
 
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