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Premium Member
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Discussion Starter · #1 ·
I rebuilt my 3.0 recently and got it bored .030 over w/ ross pistons for an 8:1 compression. When I got on it a little bit it would blow oil through the exhaust.... but only after I was done accelerating and slowed the engine down. It was bad at first when I started to get it (800-900 miles). Now that I have around 1,500 miles on it, I can get it up stronger into boost and I won't get the small oil cloud through the exhaust anymore. Now I only slightly get a smell on a very rare occasion. The engine get around 20 inches of vaccum at idle so I didn't think it was a mojor issue. This is the first engine I've rebuilt and was curious if this was normal. Any input would help.
 

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Discussion Starter · #4 ·
What was odd was the fact that it slowed down greatly. At first it was bad where I could actually see the cloud of burnt oil when I slowed down. Now I get on the engine harder and I never see a cloud anymore and very seldomly even smell it.
What exactly is a catch can?
 

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stupid booster
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i wasnt around the first few hundred miles of my engine but my body shop mech said he noticed a great deal of smoke then. NOt sure why. I now never have that problem. Does it go away completly when the engine is warmed up?
 

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Kampfbereit
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Ross pistons require an unusual amount of piston to wall clearance. You also rotated your rings 180/90 degrees from each other before you put them into the block right?

It's not something I've noticed with cp pistons to smoke, but it's not unsual for forged pistons to smoke a bit on cold starts until they are fully expanded.
 

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stupid booster
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Like i said mine did it at first but now my car sounds like stock and there isnt any smoking. Just occasional 10psi smoking my tires
 

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Resident Asshole
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icemanrld19 said:
Like i said mine did it at first but now my car sounds like stock and there isnt any smoking. Just occasional 10psi smoking my tires
:twothumb:
 

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I hate stance
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I don't know man. For the amount your talking about when you first started using them it definately sounds like you had a leak in at least one of the rings. You only have 1500 miles on the car now and you said you got on it. Every motor I've broken in I've used leaded gasoline and haven't gone WOT or above 3500rpm's until about 3k miles. Tear it down man, trust me. It sounds like you have a lot of work into this motor, don't kill it yet. I'd pull it apart and check everything.
 

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Discussion Starter · #13 · (Edited)
It doesn't matter if the engine is warmed up or not. I've been checking my oil and at first used a very little bit. They are ross pistons with oddly required only .040 (i don't remember exact numbers) instead of .060 clearance. The company specially made them for the engine and they knew it was supercharged. That's why they also only made them 8:1 compression. The rings were spun 180/90 degrees when I had them installed. I didn't realize I should have waited for 3k to really get on the throttle. The tuner shop said around 1.5k until I was able to wot it. When it started to first smoke was only around 3k rpms after around 500 miles. And the odd part was that it only started smoking after you let off the throttle. It's down to the point now where it doesn't smoke at all and i don't really smell it anymore either. I'm happier now knowing that other pistons caused this on other cars when they were getting broken in.
 

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How many miles on the VSS?

Valve Stem Seals...
 

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I hate stance
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perna00 said:
It doesn't matter if the engine is warmed up or not. I've been checking my oil and at first used a very little bit. They are ross pistons with oddly required only .040 (i don't remember exact numbers) instead of .060 clearance. The company specially made them for the engine and they knew it was supercharged. That's why they also only made them 8:1 compression. The rings were spun 180/90 degrees when I had them installed. I didn't realize I should have waited for 3k to really get on the throttle. The tuner shop said around 1.5k until I was able to wot it. When it started to first smoke was only around 3k rpms after around 500 miles. And the odd part was that it only started smoking after you let off the throttle. It's down to the point now where it doesn't smoke at all and i don't really smell it anymore either. I'm happier now knowing that other pistons caused this on other cars when they were getting broken in.
Some may have gotten past the rings before they set then. Well as long as you know it's fine now. How does the car run overall?
 

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Discussion Starter · #16 ·
The valve stem seals were all replaced. I already talked to a few tuner shops and they explained how the strong vacuum at deceleration could have pulled oil past them. The head seals were all replaced and a valve job was done on both. The car runs pretty solid without any irregular shake in it. It seems to be stronger every day now. I think I just didn't realize it took so long to break the engine in and wasn't familiar with oil going past the rings before they set it. Now I just got to get some better piping/clamps cause the boost likes to blow the pipes and couplers apart.
 

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Never Too Much HP
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There is nothing wrong with your motor... What happened is when you assemebled the motor i bet you covered the top and second ring in engine oil (am i right) what happens is that oil gets trapped in the rings and takes a while to burn out. Second, oil should of only been placed on the oil ring (if at all) and of course on the piston skirt. Rings dont like oil being all over them when you try to break in the motor. It causes all the roughness to be worn off before the rings really get a chnace to seat. Now that all the oil is gone the rings are starting to seat. Also i can not stress this enough DO NOT BABY YOUR MOTOR WHEN YOU FIRST GET IT RUNNING. Break a motor in on the track if you can, pain and simple, pound on it. If you really baby a new motor the rings cant seat before all the roughness on the walls is gone and your left with a motor that might not smoke, but CAN use a little more oil. Also when you pull a motor apart that has been not been broken in hard, you will see the burn oil on the piston under the rings. This is from the rings not sealing as good as they can. I promise you, you can not be hard enough on a new motor. We build them and break them in on the dyno all the time.
But your motor is fine, the rings are finally starting to seat, and you can start to enjoy her w/o your nice blue cloud!
 

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myrt said:
There is nothing wrong with your motor... What happened is when you assemebled the motor i bet you covered the top and second ring in engine oil (am i right) what happens is that oil gets trapped in the rings and takes a while to burn out. Second, oil should of only been placed on the oil ring (if at all) and of course on the piston skirt. Rings dont like oil being all over them when you try to break in the motor. It causes all the roughness to be worn off before the rings really get a chnace to seat. Now that all the oil is gone the rings are starting to seat. Also i can not stress this enough DO NOT BABY YOUR MOTOR WHEN YOU FIRST GET IT RUNNING. Break a motor in on the track if you can, pain and simple, pound on it. If you really baby a new motor the rings cant seat before all the roughness on the walls is gone and your left with a motor that might not smoke, but CAN use a little more oil. Also when you pull a motor apart that has been not been broken in hard, you will see the burn oil on the piston under the rings. This is from the rings not sealing as good as they can. I promise you, you can not be hard enough on a new motor. We build them and break them in on the dyno all the time.
But your motor is fine, the rings are finally starting to seat, and you can start to enjoy her w/o your nice blue cloud!
:twothumb:
 

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Discussion Starter · #19 ·
Good call! I did cover the rings in oil before I assembled them. They had to smooth out a few burrs in the seating grooves of the pistons and I put oil on them to make sure they would smoothly fit after the minor filing after they got fitted. I did baby the car for around 500 miles, hopefully it didn't effect anything major. It's running strong though. Thanks again.
 

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OMFG
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Babying a freshly built motor is considered by some to be the worse thing you can do, and can result in the rings not seating very well.

I broke my new engine-in with 15psi of boost till about 1200miles then I turned it up to 22psi and its been there for 7500miles.

At any rate, if you continue to burn oil, smoke, etc then your rings didnt seat very well or the valve seals/guides are leaking. BUt, usually you'll notice some crazy blow by if the rings didnt seat properly. Nothing you can do about it cept tear it down again and do a quick overhaul, or drive it into the ground. :bigthumb:

Whatever you decide, just have fun with it. ;)
 
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