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Compression #'s

  • Thread starter Thread starter QDRHRSE
  • Start date Start date Sep 20, 2004

QDRHRSE

New Member
Dec 31, 2002
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Palmdale, CA
Sep 20, 2004
#1
  • Sep 20, 2004
  • #1
What kind of compression #'s do you guys get when you run a compression test....that is, if have have done one? List heads and cam too please. I'm seeing 145 with AFR 185's and an F Cam. Anybody else? Is this low?
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
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128
Saint Louis, MO
Sep 20, 2004
#2
  • Sep 20, 2004
  • #2
Mine averaged 145 also with my stock cam (with sloppy 190k chain) and stock heads. Haven't retested since the P head install. My stock cam had valve events VERY close to the Crower 15510 cam.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Sep 20, 2004
#3
  • Sep 20, 2004
  • #3
im one to believe it is a bit like two guys comparing dyno runs (even from the same dyno): the relative numbers you get are what matters - not absolute numbers. there are enough variances in gauges and methods (motor warm, at WOT, etc) to create deviation. as long as they are all close, i would not sweat it.

now if i totally missed the point of your posting - my bad.

good luck.
 

QDRHRSE

New Member
Dec 31, 2002
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Palmdale, CA
Sep 21, 2004
#4
  • Sep 21, 2004
  • #4
Hissin-

No. You got it. It looked low and it got me thinking because the car is running like crap and I can't figure out why. Your absolutely right about everybody being different but I just wanted to see what the spread was like.
 
V

v8only

Active Member
Jul 3, 2003
2,378
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Sep 21, 2004
#5
  • Sep 21, 2004
  • #5
last time I ran a check on a healthy stock 5.0, I got around 150 all the way around, your #'s sound about right.
 
F

fost9508

New Member
Aug 28, 2004
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Sep 21, 2004
#6
  • Sep 21, 2004
  • #6
What about compression from cylinder to cylinder, when I have done a compression test all the cylinders get a little bit diff numbers. What is the rule of thumb when review the compression test results. i.e. all the numbers should be +- 10 psi from the highest cylinder reading....????

thanks,
 
8

87'GTstang

New Member
Feb 16, 2004
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0
Sep 21, 2004
#7
  • Sep 21, 2004
  • #7
fost9508 said:
What about compression from cylinder to cylinder, when I have done a compression test all the cylinders get a little bit diff numbers. What is the rule of thumb when review the compression test results. i.e. all the numbers should be +- 10 psi from the highest cylinder reading....????

thanks,
Click to expand...
+/- 10 percent
 
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