Compression Test Results Help
Thread Starter
Teching In
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Compression Test Results Help hey guys, i was just wondering if a 3rd to 2nd downshift(accidental) at 100mph would be responsible for the poor results of my compression test.
#1 18%
#2 32%
#3 15%
#4 52%
#5 17%
#6 30%
#7 37%
#8 33%
7 pushrods were bent but they r now replaced and there doesn't seem to be any other problems aside from the poor compression #'s. The car only has 26000 miles on it also. thanks in advance for your help.
#1 18%
#2 32%
#3 15%
#4 52%
#5 17%
#6 30%
#7 37%
#8 33%
7 pushrods were bent but they r now replaced and there doesn't seem to be any other problems aside from the poor compression #'s. The car only has 26000 miles on it also. thanks in advance for your help.
TECH Enthusiast
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From: San Diego
There is only one thing that can bend a pushrod...you guessed it, valve crash. Hold on, someone will say spring stack can cause pushrods to bend, correct, but if you have spring stack you are also gonna have...you guessed it, valve crash.
Thread Starter
Teching In
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valve crash, is when the piston crashes into the valve right? Because i had the car checked out by a shop that i trust a lot, and they said that the cylinder did hit the valve, but it did not do any significant damage. In other words, not worth pulling the head. Are those numbers bad enough to cause serious power loss though, and if so will replacing the head correct the leakage problem? thanks
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From: San Diego
Originally Posted by Jon7I2
valve crash, is when the piston crashes into the valve right? Because i had the car checked out by a shop that i trust a lot, and they said that the cylinder did hit the valve, but it did not do any significant damage. In other words, not worth pulling the head. Are those numbers bad enough to cause serious power loss though, and if so will replacing the head correct the leakage problem? thanks
Thread Starter
Teching In
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No, they said it did hit, but then he went on to say that the piston just kissed it, and did not cause siginificant damage. However, when i got home and examined the leak down test results, i became worried that this would be robbing significant hp from me. is this true?
TECH Enthusiast
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From: San Diego
Originally Posted by Jon7I2
No, they said it did hit, but then he went on to say that the piston just kissed it, and did not cause siginificant damage. However, when i got home and examined the leak down test results, i became worried that this would be robbing significant hp from me. is this true?
Staging Lane
Joined: Oct 2006
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From: Pittsburgh
I wouldn't trust that shop too much any more... Any one who can say that the piston colided with a valve and that it doesn't matter is just out of their mind. Take those heads off and then find out that you have bent valves... and then... well, have fun and make them into way better heads!
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Thread Starter
Teching In
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But thats the thing, if the valve (s) were bent then wouldn't the car b running like **** or at least poorly. Right now the car runs fine. Myy only reason for concern was the compression test results. So i guess what im really asking is r those #'s bad to the point of losing significant power?
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Verdad Gallardo TECH Enthusiast
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From: San Diego
Originally Posted by Jon7I2
But thats the thing, if the valve (s) were bent then wouldn't the car b running like **** or at least poorly. Right now the car runs fine. Myy only reason for concern was the compression test results. So i guess what im really asking is r those #'s bad to the point of losing significant power?
Thread Starter
Teching In
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dammit, i wish i knew that. I dont know, because i took it somewhere to b done, and they only gave me the %'s. In retrospect, i should have just bought the 80$ tester and done it myself. Then i would have some solid 1st hand information. But i appreciate all tyhe help.
I'm a bit in the same boat as you. I mishifted a while ago and bent just one pushrod but now I have a ticking noise on the driver side which comes and goes. I'm sure there were some valve kisses as well. I still dynoed 329HP with a lid, ported TB, ASP pulley and LS6 intake; running a lean (14.1 A/F) and having a heavier ls7clutch/LS2 flywheel combo. My fix: 243's from Patriot.
Last edited by warp10; Nov 2, 2006 at 06:41 PM.
Thread Starter
Teching In
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I'm kinda in relief that u said u did the same thing and still posted such good #'s w/ just intake components/pulleys. Hey, i was checking out ur page and i noticed that u had the slp suspension package (shocks/springs) and i was wondering how much that drops ur car.
Last edited by Jon7I2; Nov 2, 2006 at 05:42 PM.
Originally Posted by Jon7I2
dammit, i wish i knew that. I dont know, because i took it somewhere to b done, and they only gave me the %'s. In retrospect, i should have just bought the 80$ tester and done it myself. Then i would have some solid 1st hand information. But i appreciate all tyhe help.