Compression test... is this good, blow by.
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Compression test... is this good, blow by.
just ran a compression test on all my cylinders on my 370ci. 6.0 PT88mm Turbocharged...and >
all of them were from 145-148psi is this good seems to me a little low. what do you all think of this numbers. My engine is a 370ci. low compression 8.8, pistons are Probe -16.5cc with Diamond rings... top ring was gaped at .22 and second ring was gaped .26 for boost. But im having a little blow-by blowing threw the filter on top of the valve cover... looks like steam enough where you can see it coming out. but the oil pressure is steady at 38-40psi at idle and from 60-80 psi at wide open trottle. Well what do you think ? is this normal anyone having little blow-by at idle? i also checked my spark plugs and they all look real clean with no oil at all.
all of them were from 145-148psi is this good seems to me a little low. what do you all think of this numbers. My engine is a 370ci. low compression 8.8, pistons are Probe -16.5cc with Diamond rings... top ring was gaped at .22 and second ring was gaped .26 for boost. But im having a little blow-by blowing threw the filter on top of the valve cover... looks like steam enough where you can see it coming out. but the oil pressure is steady at 38-40psi at idle and from 60-80 psi at wide open trottle. Well what do you think ? is this normal anyone having little blow-by at idle? i also checked my spark plugs and they all look real clean with no oil at all.
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seems low IMO, i had a 200,000 mile sbc that had the same. it is a boosted motor though so i wouldnt necissarily call it a bad thing.
If youve removed all your pcv and ccv systems those crankcase gasses have to go somewhere
If youve removed all your pcv and ccv systems those crankcase gasses have to go somewhere
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i have probably 8.4:1 compression, rings are on the looser side, and on a cold engine i was reading 120psi across the board. i wouldn't get too caught up in the actual number (within reason), as long as they are all within a small percentage
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those reading are normal as long as there all within a few psi it usally means everything is good, now if you had some 145 and say a 135 or so i would start to worry but your readings are normal.
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thanks guys i just need to figure out good way to run the pcv to the catch can and not get oil into my cylinders. anyone have a good set-up for the pvc vacume source to a catch-can. thanks guys i just hate seeing the oil steam coming out my breather everytime i open my hood and all my friends see it.
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Hookup your PCV system and run a catch can and a one way check valve between the throttle body and your valve covers or the valley cover (which ever one you use). The check valve is there to keep the boost pressure from entering your PCV system when letting off the gas. I ran a catch can on my BBC and it worked perfectly. The only thing I'm going to change is the addition of the check valve for use with the procharger I'll be adding in the future.
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the catch can i used just got too messy. i just routed a couple hoses from the VC vents to the ground. unless you brokededdd something, the amount that comes out at any one time is negligible