Piston damage, causes?

[99riocobra]

hey guys, wanted to get some input on this. went to have my car tuned with a KB 2.6, and unfortunately had to drop it off due to time constraints. when i picked it up that night and drove it home at night i could see a trail of smoke behind me so bad i almost passed out.

what do you think would cause all of the discoloration on piston #8 like this? and all the pitting/chipping like that? now, the car was going through about a quart of oil in 10 mins of idling, so that's what all the caked on build up is...obviously the tuner did something insanely wrong, but what exactly? they already knew about the smoke issue the next day, so i'm going there tomorrow to get some money out of them as this is an MMR 900 motor with about 2500 miles on it :nonono:

here's what the head looks like on #8

and as a suprise, #6 had a broken piece and broken ring as well. i'm pretty sure the pits on this one are from the piece bouncing around. there was a point where it made a horrible rattling noise on the way home from this tuning nightmare(i was babying it as it was already smoking and going through oil), now i guess i know what it was...

 

[Brutal Metal]

I would DEMAND and explanation from MMR PERIOD!!

 

[99riocobra]

MMR? i would almost place more blame towards the tuner, like say they ran it real lean or something...

 

[Jimmysidecarr]

That is without a doubt detonation damage.

I would have some serious questions for the tuner.

Causes are possibly lean or too much timing advance for the available octane and cylinder pressures.

Not a possible cause.... would be defective forged pistons.... ummm not very likely.

Sorry to hear of your tuning nightmare.

 

[divided]

Definitely sounds/looks like a tuning issue to me. How did they not notice it? Didn't you have to sign a release though to get dyoned?

 

[mustanginky]

yeah it's definately a lean issue. my pistons were the same way when mine let go with a procharger. broken ringlands are often caused by the heat generated by pre-ignition/detonation. the rings can expand, and bundle up, then one lifts up and snaps the piston. either way, the dyno tuner made a mistake. hopefully they won't screw you over.

 

[99riocobra]

That is without a doubt detonation damage.

I would have some serious questions for the tuner.

Causes are possibly lean or too much timing advance for the available octane and cylinder pressures.

Not a possible cause.... would be defective forged pistons.... ummm not very likely.

Sorry to hear of your tuning nightmare.

gotcha, thanks a ton for the input! i'm glad to see you agree the components were obvioulsly strong enough, they just can't hold up to this incompetent tuning.

Definitely sounds/looks like a tuning issue to me. How did they not notice it? Didn't you have to sign a release though to get dyoned?

that's kinda what i thought, how the heck could they try and pass this off...nope no release signed.

yeah it's definately a lean issue. my pistons were the same way when mine let go with a procharger. broken ringlands are often caused by the heat generated by pre-ignition/detonation. the rings can expand, and bundle up, then one lifts up and snaps the piston. either way, the dyno tuner made a mistake. hopefully they won't screw you over.

ahh i see. i was actually wondering about that broken piece. that most definitely makes sense. i wonder why the rest of the pistons don't look like they show any signs of detonation though? maybe cause #8 gets the hottest usually? i've only pulled the driver side off though...

any other input is definitely welcome!

 

[getblowd]

reason #1 why i would never let my car be tuned without being there. sorry man.

 

[99riocobra]

obviously that wasn't the way i had planned it either, but due to them not informing me the 4 hours before lunch would involve waiting for their new dyno software to arrive(the other crapped out the week before) i had no choice...

 

[divided]

So you were the first car tuned with new software? Wonder if that had anything to do with it?

 

[GotBst10th]

sucks to hear man hopefully they get it squared away for you in a professional manner. btw im from stl also who did the tune as im looking to get mine tuned so i dont go there lol

 

[Brutal Metal]

Tuners that know these motors like the back of their hand Always pull a degree or 2 of timing from #7 & #8, that's pretty common knowledge!
The only reason I said to contact MMR was because you said you were experiencing problems from the outset with your motor!

 

[T-Pain808]

:fm:

 

[racebronco2]

My pistons looked bad but the ring landing didn't break off when i ran too much timing.

 

[greengt88]

that really sux man, hope they aren't another POS Company that says oh well your loss sorry. Been through that before buddy and got screwed big. Luckily i hadn't paid them before they broke mine. So i had enough to purchase another short block. best of luck let us know how it works out for you. also post the name of the tuners' shop so others can maybe be fore-warned about them. is there a thread for that....bad tuners??

 

[thomas91169]

definitely bad tune.

what timing and a/f ratio is it tuned at?

 

[99riocobra]

So you were the first car tuned with new software? Wonder if that had anything to do with it?

well i mean i was the first car with that software, but i don't think it was any different from their previous version. just a replacement or something....

sucks to hear man hopefully they get it squared away for you in a professional manner. btw im from stl also who did the tune as im looking to get mine tuned so i dont go there lol

oh for sure....tuner was Gene's Automotive in Highland, IL. i was going to make a thread on STLMustangs tomorrow after i talk to Gene's to warn people from going there. i've learned of someone else with a gto that got screwed by them recently too...

Tuners that know these motors like the back of their hand Always pull a degree or 2 of timing from #7 & #8, that's pretty common knowledge!
The only reason I said to contact MMR was because you said you were experiencing problems from the outset with your motor!

yeah you said it, no way for me to know if they did that or not. i'm gonna go ahead and guess no though...i gotcha, makes sense now :beer:

 

[99riocobra]

definitely bad tune.

what timing and a/f ratio is it tuned at?

i know it sounds stupid, but i'm not exactly sure. but i'll explain why....

i had to leave my car as mentioned above. i got a call at work later on asking if my car smoked ever before. i was like uh, no. i mean it would puff a hair after i'd let off from going wot(w/ the turbo). but nothing to write home about. he said it smoked real bad on the first pull, but then stopped so i just tried to play it off for now. anyway, i get another call later on saying hey your car's going lean after 5500 or so and pump and injector dc are fine. no matter what they try it won't take anymore fuel. all i can think of is how far did they go with the pull while it was lean, or how many times lol. so i basically told them to quit since they couldn't figure it out.

so i finally get there that night to pick it up and on the way home, while it's dark mind you, i can see the cloud of smoke behind me like i've never seen! i instantly go from being pissed to super ultra pissed. as i'm almost home i hear this insane rattling noise, which now looks like it was probably a chunk of my piston bouncing around. keep in mind that did not get on it at all the entire time for fear of not even making it home just cruising. i pull it in the garage and check the oil and fill it to full...took about 2.5 quarts if i remember right. the driver side exhaust tip is just dripping and coated with oil and fibers and stuff.

called them the next day, took the car there to have the tune pulled off and load my Bob Kurgan turbo tune back on, car behaved instantly much better(still smoked and stuff obviously, but driveablity went back up like it was before lol), and they were at least kind enough to refund me the $400.

with all that said, i never even concentrated on what the timing or af was because i never considered the car to be tuned. iirc timing was 15°(since it was 20psi on pump 93), and af was rather lean and definitely in the 12's. like 12.3 or so...

i'll be calling them tomorrow and emailing the pics.

cliff notes: NEVER go to Gene's Automotive in Highland, IL

 

[MoKo_03SVT]

wow man....sucks to hear/read. BIG TIME!

hope they take care of you on this. keep us posted with updates as you get them, please!

good luck

 

[THEhamBone]

One of 2 things happend. Let see if it was your fault or not. You dont have to post if it your fault, that will save you some shame.

1. Bad tune.. leaned out.. detonated..

2. You raising hell with you new tune, blowing the tires off. Spinning like hell bouncing off the rev limiter, heat soaked as hell. When you were bouncing off the rev limiter waiting on it to catch traction it detonated. ka boom.