ring from the broken piston measured out at .010 in the new motor in any bore. These bores are tighter than ones with 55K miles on it so, I am glad I went with .014 for my top gap and .019 for my second gap in the new setup.

I think yall missed the best advice in the thread.

Regular 1st ring, gapless 2nd ring, regular oil control ring pack. Its crossed my mind a few times already.

hum...I would think you want a gapless 1st ring so it can prevent the majority of combustion gasses from getting past and then run a regular second ring so if they do it will allow them to escape and prevent ring flutter.

I would think a better seal on the 2nd ring than the first is no bueno.

I briefly read Total Seal's page on their rings but that was my take on it.

TechPage

I wonder if @SPEED6 KILLAH; has any experience/thoughts on these type of rings? or anyone else for that matter.

@Lex;

I can send you the ring in question along with some others...you just have to see how clean the one side is. I'm telling you it looks polished :)

although I suppose it could have bee polished after the failure with all the moving parts in that area with the land broken.

chicken <> egg lol

What I am thinking is that once the ringland broke fuel really washed that area out. It would be telling if we saw carbon being removed form the other rings where the ringland was still intact.

@Rokusek; Once you get @tastysi2004;'s block out post pics of #4 here.

This has been the thread I've been reading off from.

DAMNIT!!!

I didnt want to be brought in here, i just wanted to lurk and read as much as possible lol


To late now...


Idk how soon thats going to be it all depends on Mauro and how long he can be down for, and getting the block to the shop ASAP! It can be ripped apart in a day easy, but the down time is what he doesnt want so we will have to buy what i know he i will need for now, then once we pull the motor and get the block to the shop then we will know more.


Ok so @tastysi2004; had been having some issues with smoking, at first we thought it was the turbo, I told him to put an OCC on the car and that would help fix the smoking problem. He put the OCC on and all the white smoke went away. (He already had the Bnoon Bolt)

Well that allowed us to see the Black smoke that was being masked by the white, as well as the smell. Absolutely horrid burnt oil smell. When he let off after a hard WOT pull the car would just pour black smoke out the back for a good while. He was having power loss down low. I told him several times we needed to do a compression check and see what the hell is going on with his car. Because something was obviously wrong with it.

So Sunday morning in MD for MNM, we did a warm compression check and found 160/160/160/130 (1,2,3,4). #4 's plug was a oily. and he has some serious knocking coming from right in between #3 and #4 . (used the screw driver method to hear for knocking)

Also checked plug gap @mzr0818; do you remember what that was?) dont remember as i was more concerned with the compression test.

So he drove back to VA Beach from Bethesda MD and said the car was great the entire drive back to hampton roads but right as he was getting home, the car started Knocking hardcore. (what ever hardcore is idk).

As soon as we can get into it and tear it down I will be sure to get some good detailed pics to post up here.

/end failure report

Yes. .030, .030, .031, .030

1-4


Just a thought I was showing crazy ass knock on the AP when mine was cracked. Did he moniter any??? Also I called that shit...



EDIT #2 This is the thread all the cool kids are on...

My knock was ranging from 3 to 8.1 right before I pulled into my place.
After letting my car cool down I had to go make an errand and she knocked 2.5 at most.

There was no knocking nearly the entire ride home?

Yup thought so. Mine was in the 8.blaa blaa at times the day before I parked her.

I saw knock at 2.5-3.0 levels on bumpy roads only. Aside from that, no knock until I got home. I kept a close eye on knock the entire ride home. Haven't started her today. I want to check for some metal shavings in the oil pan.

update..

motor: 98,xxx miles
compression 165, 160, 170, 131
sludge like a mofo in the motor
knock was usually 8.1 everytime i drove her.
after i found that certain ticking noise.
piston #4 had a cracked ringland. about 2 inches of it.

Finally I have received the ring gap info from EvoX builders here.
They do it this way:
1st: 0.45mm
2nd: 0.45mm
Oil: 0.5mm

These figures seem to be close to oem DISI specs...don't they?

2nd ring yes but not first

OEM spec

http://mail.netsecurenow.com/img/bui...oemringgap.jpg



I just recently completed the assembly of my virgin motor with Gen2 pistons I opened up the OEM gaps as follows.

1st: .35mm - .014in
2nd: .48mm - .019in

Interested to see if your guys have trouble running the same gap in the 1st and 2nd ring. any gasses that escape the 1st ring may get trapped and cause the rings to flutter. At least that't the reason the 2nd ring is always speced larger than the 1st.

Just got word on my pistons. I will update when I get more.

Year/model: 2007 MS3
Mileage: Exactly 95,000 miles
Compression: 180-180-180-90
Cylinder with cracked piston: Cracked ring cylinder 4
Suspect event : old age and motor being pushed. Cylinder 4 misfire. Car almost overheated over the summer due to thermostat. HT65 turbo installed at 30,000 miles with 390tq. BNR installed at 88,000 miles with 390-400tq. So 65k miles at 390-400TQ. Spraying meth for most of the engines life as well.

Attachment 104030
Attachment 104031

Thanks, taf. I'll update OP when I get back to my desktop.


Sent from my iPhone using Tapatalk

I hate reading these threads...knowing that my engine is destined for fail.

"Every engine dies, not every engine really lives." William Wallace

Ok so, is everyone at risk for this? Or only big power guys, guys who do track time, really high mileage guys, guys running assloads of timing with Meth/E? I'm lightly bolted but have been running 2 gals of E85 and about 4-5 degrees more wot timing than the last OTS maps (before the new pure boost 2.31's). Never tracked, but definitely beat on it in the heat when I was tweaking my tune and logging for summer temps. Saw BATs hit 170F on the stock TMIC. ECTs got to 190s.

For its worth, I NEVER have had to add any oil between 5000 mile changes. I fill to H, and check before I change it and it's still at H. mileage is 47,000 on an '07. Only smoking I ever see is when I go WOT after cruising for a while, I'll get some black smoke, but only the first time and then it will only happen again after at least another 10-15 mins of cruising. But it's done that forever. From reading (most of) this thread, my impression is that mildly modded, street-driven-only cars with a moderate tune don't need to worry, but I want to make sure that running E and the additional timing isn't an issue...

So not #3 this time but the same exhaust side of the piston. We're starting to see a pattern.
@taf0422; did you start noticing the misfire and symptoms after a particularly hard run or hot event?

Possible that high egt's are to blame?

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Driving home, thinking about my car, getting fucking pissed off.

compression is down to 150 now in cylinder 4.

I was running a god damned OTS stage 2 map, 4 time attack events last year.

Im at 45k kms now, was at 31k when i found low comp after the summer.


motherfuck.

ok here are the variables.

penz plat 5w30
was running oil temps of 260F, would run ~5 laps at that temp and then come off.
One day i had couplings blow off multiple times
i did an oil analysis after the last track day, low shear, plenty of additive left, only thing they made note of was high silicon content. (silicon in the piston alloy?) i think there was 5k kms on that oil, but at least 2 time attack events on the oil


what is making me mad is all the dudes running on the track with stock internals and having no problems. What has happened thats any different?
in regards to oil temps, @super_pablo_; is running in god damned arizona. What are your temps?

Wonder if extreme ambient temperature differentials have any issue here? Is there any coloration of ringland failures and climate? Just a crazy idea that popped into my bald bean?

A little more part throttle knock on the highway and some smoke from the tailpipe every now and then. Did a quick WOT merging into traffic and the check engine light came on with a misfire when I got to the next light.

Unfortunately I dont have oil temps to give you, although Im planning on getting an oil temp gauge soon.
Ive seen water temps around 230-240, and I have an oil pressure gauge that see drop pretty fucking low when I come off the track... but other than that, I cant help.

it's because you weren't running rotella from the start like we told you. only reasonable explanation at this point, since you say you weren't vince tuned. it's funny, because your reasoning for not using it, was so that you could protect your warranty if anything happened, and now something has, and you're not gonna bother even looking into your warranty. ironic actually.
i don't think i've seen any ots maps that support meth injection though...
...and i thought you WERE tuning with vince...

I wasn't running meth last summer and started tuning with vince in the fall. is oil a variable that has been tracked in this thread? Penz plat 5w30 is run by a lot of people and my uoa looked fine. Blackstone said the silicon could be due tona dirty air filter which is possible as well. Really, we are all guessing here.

I don't think oil viscosity will have anything to do with it with one exception, but the thought of a 30w oil at 260* oil temperature makes my asshole pucker up.

The one exception would be, lower weight oil means less pressure, particularly when hot, which could conceivably mean less flow thru the squirters and less cooling of the piston.

Zigatapatalka

did you check compression before you started tuning with meth/vince?

Late to this party, as I am usually.

I had cracked ringlands in cyl#3. I was cruising down the TP at 75ish, got off, coasted to a light, and she died. Babied it back to Pablo and that was it.

Mods were, I, TIP, DP, HPFP, no tune.

I do not have any other particulars.

wonderful - just another thing i have to worry about with this damn car

You can probably add the modifications, tune, etc.

The pitting on the sideskirts of some of these pistons look like detonation marks.

Long scratches or scoring are normal on the sideskirts but pitting is a little strange.

http://www.mazdaspeedforums.org/foru...850.312258.jpg

HOW IN THE FUCK DOES IT DETO DOWN THERE!!!!!?????

I know it _looks_ bizarro, butt, damn.....

after the ringland breaks would be my guess.

detonation is a quick pressure spike that can resonate through the piston. The ringland is close enough to the piston head and weak enough to snap from those pressure waves.

Also it is possible I think @Lex; mentioned this too that maybe it's fuel passing the first ring and then through pressure spikes through the fluid that is helping to break the ringland. (think liquid in a beer bottle and hitting the top and then the bottom falls off)


Edit: I'm retarded.

This is a head scratcher since I've seen that pitting now on several of these broken ringland pistons.

Lex, have we seen any gen 2 pistons that were confirmed broken ring lands or just gen 1 so far

Sent from your couch

So far I don't think any pu's have confirmed. Breakasteatre is at the speculation stage of problem solving.

This will be interesting to watch.

If broken gen2 pistons start to show up soon, that means it's a power/heat related failure of the OEM part since a good number of people are pushing the motors now versus 3 years ago.

If it's a fatigue issue or a gen1 design issue, we won't see gen2 failures until later and perhaps not as frequently.