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Cold Leakdown Results - what do you think?

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Old Jul 21, 2012 | 10:35 AM
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Default Cold Leakdown Results - what do you think?

Hi Guys,

Finally getting close on my build and I decided to do a leakdown test on the motor before I button everything up. I made all of these measurements at least twice. This test is on a cold motor, 28k miles on the bottom end, hasn't ran in 9 months. All leakage appears to be into the crankcase. I'm curious what everyone thinks.

#1 11-12%
#3 2-2.5%
#5 <1%
#7 2%
#2 1.5%
#4 1%
#6 1-2%
#8 4-6%
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Old Jul 21, 2012 | 11:17 AM
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Did you just rebuild the entire motor or is this just a heads and cam swap?
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Old Jul 21, 2012 | 11:34 AM
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I am wondering same thing...has bottom end been rebuilt Previously or is it a factory assembled bottom end?
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Old Jul 21, 2012 | 02:42 PM
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Nah, bottom end is untouched. I'm testing partially because I want a baseline for the future, partially because I fear a head gasket leak, and partially because I want to play with this toy (the tool). The factory cut on the deck left scores at the top (closest to intake) of each cylinder on the passenger side. On #8 you could hang a nail even after my in-car deck prep per Tony Mamo's procedure. . .I could not have removed it by hand and it did seem just fine with the OE head gasket. #1 seemed perfect and I feel like that is just rings, it just surprised me it was +10% compared to the others.

The article below says to me that I dont have much to worry about (variation as high as 10%) but I've learned more than once over the last many months that I dont know what I dont know, especially with these motors.

http://www.carcraft.com/techarticles...r/viewall.html
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Old Jul 21, 2012 | 10:53 PM
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Yea I would wait until you have the motor hot when you getting it running it would prob give a better indication of what you wanna know...the mls gaskets are very forgiving so you should be cool on that low mile of a motor
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