if you look closely at what's left of keith's piston [ckmazdaspeed] it appears to be sorta "sand blasted" by deto/PI. I guess its hard to tell if the blasting occurred pre engine explosion or post...lol you can see where the carbon is starting to get etched away and silver piston top is beginning to appear. Esp to the right of the red sealant.

I'm glad you told us that was a piston Dano... LOL. I may have thought it was an ashtray.

Can you upload it?

I would like to read that.

Yeah, my plugs are much cleaner with E85 than they ever were with gas. No spackling, no soot.

@Lex - I just downloaded it, don't do it!!

I'll post it in VIP or some shit.

You rock. Please post a link.

@phate pulled the spill valve, took it all apart, and it wad spotless clean.

Idk why the damn pump is making that sound.....maybe when we have an install meet come spring u can help check it out lol.

Gonna have to wait until tomorrow. Silly document protection.

Lots of ways around that depending on what type of doc...

This works awesome for .pdf that don't have a password to open the file:

http://freemypdf.com/

Apparently it does have a password to open it. It didn't when I first downloaded and auto opened, but it's now locked or some shit. I printed a copy, so I'll just scan it as a new pdf and upload that shit, lol.

Not the SAE paper, but it might interest some of you.

A sad day today :(
Attachment 48830

Attachment 48832

Here is an article on reading spark plugs after alcohol combustion:

Blown Alcohol Spark Plug Reading 101 by Mike Canter

I don't have enough time to read the last two pages and see what I've missed right now, but I have an interesting opinion about what happened to my engine to throw out there... and I'm not sure, but it might be related to the pre ignition you guys are talking about (I just gave a cursory glance over the last page.

Anyway, I dropped my head off at HTP yesterday for Matt who is building my block. He has been in this business for over a decade, if not two, and is a fucking genius. If he had more focus and time mangament skills, he would be at the top of whatever route he choose in the car industry... along the lines of fabrication and tuning at least. He used to tune evos while fabbing parts, but now just fabs (i just fap... pretty close, right?). Anyway, he is the shit! He was building joels block and is the guy finishing the AWD speed 3 from columbia missouri

So, I told him the theory that I was past MBT and that it caused me to blow. Now, he did not say he was positive, but that he was pretty sure that was not caused my motor to go from the looks of the head. He did not see the piston, but I explained as best I could what it looked like. i will bring it in when I go in today. He then tried to explain it to me, but I didn't know he enought to make sense of what he was saying.

So, here are some photos of my head and a shot with a much better camera of the piston... maybe this will give you guys more info as to what happened, or maybe everyone will still think it was too much timing.

http://i1226.photobucket.com/albums/...5/DSC_1084.jpg

http://i1226.photobucket.com/albums/...5/DSC_1083.jpg

http://i1226.photobucket.com/albums/...5/DSC_1082.jpg

http://i1226.photobucket.com/albums/...5/DSC_1085.jpg

http://i1226.photobucket.com/albums/...5/DSC_1080.jpg

^ What's the story? Under what circumstances did it blow, was it knocking etc??

Also is that a 2010 because the pistons are different from a gen1 and in a good way. Different crown with dish to disperse fuel properly and a lot less soot and build-up.

Last few pages of thread here:

http://www.mazdaspeedforums.org/foru...ml#post1193025

(That is ckmazdaspeed3's car / 2010 ms3)

Just read that. The stuttering was a sign of an issue in CKs car. The shock of power on/power off when it stutters is not so healthy for the motor.

That and he was making quite a bit of power and reving to 6800-7k RPM? The other pistons don't look bad from what I can see but there are marks on the head around the quench areas.

His builder was particularly interested in what the head looked like as well.

I'll look at this more when I get off work tonight, but I posted this cuz I was using four gallons of eth and had really advanced timing and it was originally thought that that was the reason I blew. I just wanted to post the counter opinion that timing did not kill me. Afterall, dano ran noticeably more timing and is ok... But two different opinions from two very intelligent people. I'll see if I can get more info when I talk to my builder today.

Really looking fwd to this paper - thanks!

The silent "killer" - pre-ignition would have probably done more damage to more pistons/piston tops. Looks like the rod let go in this one. Not ruling it out, but there are other possibilities.

EDIT: Really you should be seeing some heat damage/melted bits such as the spark plug tip if pre-ignition was occurring. Colder plugs, cooler charge, and more fuel to cool all help keep pre-ignition at bay.

There's also another elephant in the room. When increasing timing and making clean power you are increasing cylinder pressures. Add a bigger turbo and higher RPMs ... those are all stresses on the engine that are far far beyond the design specs.

Just because a tune is solid and there's no knock doesn't mean the stock parts (or any parts for that matter) can take infinite amounts of cylinder pressure and mechanical stress. How long had you been running E and the big turbo?

I am also very interested in the 2010+ car piston design and how clean they look compared to the gen1 cars. Mazda did make some changes to the internals.

After talking to my builder today, he says that due tothe condition of the rest of the head, he is sure that it was not caused by being past mbt. Also, it was not preignition which lex already eluded to.

Also like lex said, it was simply too much cylinder pressure, but obviously the question is, was it one catastrophic moment, or just wear and tear.

Lastly; it was my piston that broke, and not my rod according to him.

I can't remember if I posted this in my build thread or not, but here is the other side of the damage.
http://i1226.photobucket.com/albums/...5/DSC_1086.jpg

There's some pitting on the piston in the right of that picture ... I assume this came from parts circulating through the motor - otherwise that looks like detonation.

I would also be weary of high power high RPM runs. The higher RPM really stresses the rotating assembly.

What are you doing with the broken parts? If you're going to chuck them I'd like to have a rod and piston shipped my way to compare these to my Gen1 parts. I can pay for the trouble of course.

I see what looks like metal shavings or coolant/oil all over the head and block; I think that's what you're seeing on the other pistons. I don't think it's pitting.

I believe that Daniel is correct, but I am happy to take any pictures that you guys want me to take.

I actually may have some gen 1 pistons that Dustin sent me. I was going to use them in my build, but after talking to Matt yesterday and hearing hist thoughts, I am going with something stronger... What is $500or a bit more, if it adds longevity to the motor?

Anyway, @Lex , when I take it apart, I will be happy to send a piston your way... And if you or anybody else wants anything for research, just let me know.

Excellent, a complete piston and rod please :)

Back on the subject of black death, my pops just had a fantastic idea that I built upon a little. What could help us significantly with the black death issues is a virgin grade Teflon washer to be used as an oil scraper, with return spring. The whole thing would fit inside the stock return spring and effectively seal off the internals from excess oil. He mentioned that something similar was used on hydraulic systems on aircraft to keep nasty shit out, without hampering lubrication (or something like that).

Either that, or someone can have a new retainer nut milled with two o-ring seats instead of just one, and hopefully that would work.

wipe the piston tops off and take some pics...that will rule out water droplets/shavings. This would be invaluable information for the cause.

as far as my timing is concerned, I don't know if I was beyond MBT or not but after talking with Dustin and hearing what some others have said I do think my tuning logic was flawed. oops have already checked plugs and compression and its the same it was over a year ago.

I was increasing advance until I saw a DROP in power but apparently there is a plateau in power while you initially pass or are right at MBT. This coupled with the inherent possibility of the lack of accuracy with VD could mean I was in fact running beyond MBT for a time. I only pulled 1* of advance from where I saw a power loss.

I only ran it that way for about a month when I got a new intake and so switched back to pump gas and uber low timing to run the maf cal, which is where I'm at now...[car feels like my wife's MZ3]

It's a very fine line for finding MBT, and I don't trust vd to get me there accurately. Get on a real dyno and start tweaking timing!! It'll only take like an hour if you have everything else in line :)

does anyone else think that piston had issues for quite a while before things let go for it to be so much darker than the others?

Like a ring land went and oil was getting into the cylinder causing his misfire codes. @BlueStreak had a ring land go so this could be another MZR to have this issue. and to think I rag on my scoobie buddy about his...lol

I'm guessing the plug was smashed and fuel/oil was sprayed around everywhere, which is why that piston is 'wet'. The way to tell if the wetness came before or after the venting of the block is to look at the parts of the piston that were beat-up. If they're dry, the piston was wet prior to ZZB; if they're wet, the piston was wet after ZZB.

ok..very true ...time to wipe things down and see what things look like.

IIRC he was having random misfire codes for awhile before ZZB. Just trying to look at all the evidence. I would think if the black stuff wipes off then yes it happened after but if its caked on, which it appears to be, then it was happening over time.

I would have to agree Dano, from the looks of the photo, that cylinder had something going on for a while.

Hey guys, phate just noticed something that I mentioned in another thread and suggested I put it here. So, because it may be of some help determining what went wrong with my motor and helping avoid something similar happening to others running eth, I wanted to mention my method for filling up.

I was not as methodical as I should have been, but it still seemed that it should have been fairly accurate. I would always wait until I was on E, and I would then add 4 gallons of eth. Then I would top it off with 93. Now, I drive A LOT for work, and can say that on every fill up, I was within a gallon of 93. So, it seemed in my head that if I was dialed in at 4 gallons, that additional change shouldn't hurt things too much.

... My thought was that DJ once mentioned that adding 2 gallons of eth to a tank was not enough to warrant a maf cal, so I figured that at most my fills would never vary by that much and I should be safe, but I guess that my reasoning was possibly flawed.

Also, possibly the change to winter blend added to things, but my fuel trims were never that whack. I always monitored them via my aeroforce gauge, and they peaked at around -10-11. In fact, at the start of that day it was much lower, but after doing like 30 pulls it hit -11ish.

And, as of my last log, my AFRs at WOT were either spot on our like .1-.2 richer than targeted.

Here is a log from December 3rd, it is the last that I took. :( My targeted AFR at WOT was 12.1 and you can see my fuel trims are at -5 and -7 which were around where they normally fluctuated.

Again, just posting to get as much info on the table as possible so other eth heads can sleep easy.

I would say its always better to put in the same ratio of fuels and don't use the "top off" method. I can always get 4/8 gallons in my tank if I am anywhere near empty and so that's why I use that ratio to = 12 gallons. The top off method could actually get more 93 concentration over time. Better for your AF but possibly worse for timing/Knock resistance depending on the tune and E mix.

Same principal for the winter blends, you have less ethanol thus richer AF but possibly less knock resistance.

Keith, if your trims were that negative you were probably fine where AF is concerned at WOT where they cease but you might have experienced more knock if your mix was trending toward less ethanol.

I currently believe cylinder 2 had issues way before ZZB. Have you had a chance to try wiping off the carbon from the piston top?

Well i pulled my spill valve and took it apart....and it was spotless clean...but I still sprayed it down to make sure it was clean, and I haven't got that grinding/spinning sound at cold start up now....idk what it was.....I'm back on 85 right now, we'll see if it comes back.

I was able to find the properly-sized double O-ring for the HPFP, and I was also able to fit an additional regular O-ring in the groove. I put the setup in my pump on Saturday, and I'll report back my findings. I've been averaging 5-7 days between spill valve cleanings, so it shouldn't take long to determine if this works.

This is great news Silva...keep us posted bro.

This is unlikely to fix the sticky spillvalve issue, unless that is directly caused by the oil breaking down (which it shouldn't, because it really isn't; at least not totally).

I'll start looking around for a virgin grade teflon washer to attack this from the other end of the spectrum.

Pre-Ignition characteristics paper is in the library.

has anyone tried mixing a little ethanol and engine oil together and heating it before it ignites obviously to see if whats left is comparable to the sticky crap gumming up peoples pumps?

That is great news, do you have the sizes of the o-rings?