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  #31 (permalink)  
Old 06-27-2012, 09:39 PM
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The ring tension is what it is, so probably not a big deal. Besides cylinder pressure you're looking for variation between cylinders, the wet/dry is to see if there's any difference. That will point you to rings or valves depending on the values you see or changes after the wet test.

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  #32 (permalink)  
Old 06-27-2012, 09:44 PM
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I'll try to get the wet test done tomorrow and I'll let y'all know how it goes. Thanks for all the advice and pointers. Learning something new everyday.
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Old 06-28-2012, 08:07 PM
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Warm engine is better especially with forged pistons! rings and pistons expand as they warm up increasing ring tension and decreasing piston to cylinder clearance and ring gaps decrease! but cold is ok if you have burn issues If you dry test and compressions down and you add oil to the cylinder (wet check) and compression comes up you have bad rings if compression stays the same wet or dry you have bad valves or seats! A leak-down test is how long the cylinder holds compression pressures and only tells you it leaks it doesn't pin point where it could be, head gasket ,rings, valves or seats, a crack etc, etc,

Chris
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  #34 (permalink)  
Old 06-29-2012, 04:17 PM
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your not suppost to put anything on the rubber seals that go in the front or back they will blow out everytime.

i throw them in the garbage where they belong and use a thick and i mean thick bead of silicon and torque it down a.s.a.p! never had an issue and ive done it at least 50 times.

the 2 times i tried the seals leaked both times!

if you think there is a serious rise in pressure put a cheap gauge on a vac port and see if its excessive
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  #35 (permalink)  
Old 06-30-2012, 05:39 AM
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Quote:
Originally Posted by Michael 9111 View Post
It was bored years ago. Has two sleeves in the block. Haven't had it checked for straightness since bored. It has a Lanati voodoo cam. 600 lift 110 love separation. Can't remember duration off top my head. My compression test I ran is all over the board. Goes from lowest cylinder being 110 and the highest being 145 and the rest inbetween. From what I hear there shouldn't b that much of a difference. And I checked my blow by. When I first crank it up it has no blow by. After it warms up it's has a little at idle but if raise the rpm to say 1500-2000 rpm there is no blow by. Im stumped. Maybe bad rings. Maybe worped cylinder. Idk. Besides it blowing the intake gasket it runs great in my opinion.
Seeing your blocks has been sleeved and it has not been plate honed there is a good chance ring seal is your problem, You need to do a leak down test at TDC which will tell you what going on.

Blocks that have sleeves the cylinders next to the sleeves will not be round more so once the heads are torqued on.

Plate honing is a must for good ring seal.

Here is a link on plate honing.

Values Of Torque Plate Honing - Team Camaro Tech
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  #36 (permalink)  
Old 06-30-2012, 01:19 PM
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What kind of rings are you running and what were the gaps set at ? Im just a little interested, are you running forged or cast pistons, what was the piston to cylinder wall clearance at their tightest points If you have no knowledge of this forget I asked! I was interested because 10 years ago it was bored honed and piston clearance was checked and ring gap set for 30 over and the type of rings and pistons installed! and now its been re honed besides 10 years of ware so those cylinders have been opened a little more! there's a formula for setting ring gaps for every inch of bore and different pistons & rings. For instance the Hastings rings I installed last: set at .0045" top ring for every inch of bore, second ring .005" for every inch of bore.
You cant pick up a repair manual and look up ring gaps and set them to those settings once you have strayed away from factory blue prints! If your bores are a little wore from being true (say .002") in some areas, cast rings are more forgiving in bores with a little ware then steal molly, and others! So I was Just a little interested in what you did during your freshening or who did it for you? Did you use .030 over file gap rings say .005 or .010 to make up for the ware and hone or just install .030 over rings?

Jester
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