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Possibe Uh-Oh on compression!

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Old 03-25-2007, 02:37 PM
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Possibe Uh-Oh on compression!
I did a compression test today on my 100k mile KA24de in preparation for turboing it and came across a possible problem. I dry tested it and the results were about 150psi across all 4 cylinders. Is this too low to turbo?Should I look into this or just assume that the gauge isnt accurate, since the results were solid across all 4 cylinders?
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Old 03-25-2007, 03:15 PM
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did you you let the engine reach normal operating temp. just curios because if you didn't you could get low reading when checking compression and doing a leak down test.
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Old 03-25-2007, 03:17 PM
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the trick to see if its blown rings is to drop a few Table spoons of oil in the cly that you are checking, if the psi goes up,, they are gone up bro..

warming is cool but not needed. since this method can be used to check a motor in the junkyard with no way or warming.. it is also the method used by importers ( should be) of engines

psi levels
standard 179 @ 300rpm
minimum 151 @ 300 rpm
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Old 03-25-2007, 03:20 PM
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Yeah, the car was all warmed up. If it is the rings i assume I will have to replace the rings before turboing it?
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Old 03-25-2007, 03:23 PM
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in that case do the rings forged pisons and rods
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Old 03-25-2007, 03:27 PM
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X1000

stuff is much affordable bro.
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Old 03-25-2007, 03:50 PM
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parts are usually cheap it's the labor that will make you go broke. that's why i do all my own work.
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Old 03-25-2007, 03:57 PM
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yea if you know what your doin you can do new rods and pistons in a day theyre easy to do its just time consuming
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Old 03-25-2007, 04:50 PM
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Originally Posted by jramosthe1st!
parts are usually cheap it's the labor that will make you go broke. that's why i do all my own work.
X2007............
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Old 03-25-2007, 04:50 PM
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yea 150 is pretty low, id replace rings before boost. lol i read 140 all across. im picking up sohc pistons soon tho and some new rings. 172000 ftw
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Old 03-25-2007, 05:02 PM
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Originally Posted by Biggamehit
X2007............
ok you lost me bro.
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Old 03-25-2007, 05:06 PM
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lol hes agreeing with you.
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Old 03-25-2007, 05:09 PM
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well yeah but what's with the numbers?

so i could say mfwx20000000000

that's me for the win by the way.

and here we go off topic again.
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Old 03-25-2007, 05:23 PM
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na bro its on topic lol.. it with-in helping our buddy with his compression issues lol
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Old 03-25-2007, 05:36 PM
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what i would do if i was you head to a junk yard get yourself a ka24de from a junk 240 and rebuild that.Drive your car until it explodes
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