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Old 08-29-2014, 11:38 AM   #26
danger1138
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Same here fellas, mine never smokes at all either and with loose clearances.


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Old 08-29-2014, 01:56 PM   #27
niemkij
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If you have larger flowing injectors than stock, tuning can be an issue. I don't remember the exact tables, but an adjustment is needed to the "cranking" tables. Otherwise, you can get too much fuel while cranking, washing and burning the oil off of the cylinder walls. I had a small bit of blue smoke at startup from time to time after a motor build. Once I adjusted my cranking tables properly, it has gone away for good.

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Old 08-29-2014, 06:07 PM   #28
Hyper
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Quote:
Originally Posted by 2Fast4U1DAY View Post
This^^

Ring gap placement is crucial on any engine. Depending on the product and application I try to keep gaps 180 degrees from each other if possible. Never less than 90 degrees apart either if I can swing it.

never thought about it, but makes perfect sense
do they have a tendency to turn? sometimes mine smokes, sometimes it doesn't
I do have considerable amount of oil consumption, probably due to Cosworth piston to wall clearance in accordance to Cosworth manual
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Old 08-29-2014, 10:01 PM   #29
BeastianSTI
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Quote:
Originally Posted by Hyper View Post
never thought about it, but makes perfect sense
do they have a tendency to turn? sometimes mine smokes, sometimes it doesn't
I do have considerable amount of oil consumption, probably due to Cosworth piston to wall clearance in accordance to Cosworth manual
No they do not turn. The only motion they really experience is perpendicular to the side facing the top of the piston. Piston to wall clearance is only part of the equation. The ring end gap is equally if not more important haha.

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Old 08-30-2014, 06:37 AM   #30
daslog
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Quote:
Originally Posted by BeastianSTI View Post
No they do not turn. The only motion they really experience is perpendicular to the side facing the top of the piston. Piston to wall clearance is only part of the equation. The ring end gap is equally if not more important haha.

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Here is what Topseal says on ring rotation.

"Crosshatch is also important because the amount, depth and angle of the crosshatch in the cylinder bores determines how much lubrication the rings receive and the rate of ring rotation."
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Old 08-30-2014, 08:10 AM   #31
SpongeBobSquarePants
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I have a good feeling I'm gonna have to pull my motor and take it back to element tuning. Motor smokes on startup and knock sensor picks up what might be faint rod knock. Confirmed this with my det cans. FML only 1800 miles

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Old 08-31-2014, 04:19 AM   #32
BeastianSTI
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If the rings rotated then ring placement wouldn't be as significiant. They might move SLIGHTLY but nothing significant

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Old 08-31-2014, 07:58 AM   #33
daslog
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Quote:
Originally Posted by BeastianSTI View Post
If the rings rotated then ring placement wouldn't be as significiant. They might move SLIGHTLY but nothing significant

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My internet research says they rotate at about 10 RPM. If it's on the internet it must be true....

Link to a study on the effect of piston ring rotation http://www.google.com/url?sa=t&rct=j...74115972,d.eXY
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Old 08-31-2014, 11:38 AM   #34
2Fast4U1DAY
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They can an do rotate on every platform, except for the EJ's. They don't move much if at all. I tore down my friends engine that I built for him three years ago that had 8-10k track miles and I didnt notice much if any movement from the initial installation points.

Rings form a labyrinth type of seal, hence why ring gap placement is critical. By placing ring gaps 180 apart you decrease the likelihood that they would ever line up with each other in the event that they did rotate a significant amount.

But on the other hand, we must remember that rings are free agents that can rotate at will in any direction. There is no rhyme nor reason
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Old 09-01-2014, 10:00 PM   #35
mopar3.0
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fyi I trimmed my cranking fuel and no smoke as of yet. but its also cooling off here so the oil is now thicker on start up

car had 740cc injectors
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Old 12-07-2014, 09:58 PM   #36
daslog
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Quick update on this: I finally have the the engine torn down. The oil rings were pinned to the bottom, and I realized that it's pretty easy for this to happen when you put on all the rings before you drop in the pistons.

When I assembled the engine, I did all the rings first, not realizing that the top for pistons 1 and 3 becomes the bottom when compared to pistons 2 and 4. (think about it for minute, lol)

Also, the compression rings did move a little bit, but not that much.

I'll post more when I put it back together.
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Old 12-10-2014, 11:34 PM   #37
neven22
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I had the same problem with my ,,, exhaust valve seals on both sides ...
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Old 05-26-2015, 08:19 AM   #38
daslog
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Good Morning,

It turned out to be the oil rings pinned wrong on the two pistons. Always nice to solve an issue.
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Old 05-26-2015, 11:16 AM   #39
farmboss
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i had the same problem....The engine builder at agile automotive said that a cylinder was probably out of round.

But they blamed me for improper break in and voided the warranty. Had to pay them again for all the work to put new rings in. I figured it was either seals or something was wrong with the rings on one of the cylinders but I never got an answer.

Got 16k on the built block and its going strong so far.
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Old 05-20-2018, 11:30 AM   #40
orangedot3083
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We're well in to 2018 and this thread is still paying off, thanks for everyone's input!
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Old 05-20-2018, 06:12 PM   #41
daslog
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LOL. I solved this by tossing the old block and heads into my spare parts piles and rebuilding a 2.0 into a 2.2 stroker. 285 to the wheels

In hindsight, I think it was the rings that caused all that smoke.
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