I will bet the Blown Piston in my 2011 JCW looks just like that. Until we can get the motor opened up I will never know. Lawyer told me to leave the car in PDX as MINI USA had it towed there not me. He is pushing for Lemon law which they refused and now goes to arbitration. After 30 days at MINI PDX they would provide nothing more than warranty denied for overrev but refuse to say what RPM. All they would provide was an estimate for $8630.20 with no detail of what that included. After 5 weeks I confirmed it would be a remanufactured motor but could not confirm it was even a JCW. WA Lemon Law states if the car is down for 30 consectutive days it is subject the Lemon Law. I could not even get any detail after 30 days of what they were doing or any sopporting evidence than they said so. Or what they read on the internet.

 

Dang, how much boost were you getting on the Alta/Accessport map you were running at VIR when you stuffed your car into those tires?

Didn't Mini blow up a bunch of motors when developing the JCW for this engine, finally having to change the internals?

 

Thanks for the explanation. Mine is using 1 litre approx every 1,200-1,500 miles. BMW insist they are ok upto 1 litre per 1,000 miles ???

 

With anecdotes of stock engines giving up the ghost, I wonder if any boost increase is a good idea for the daily driver.

 

Can you post pics of the top of the piston, combustion chamber in the cylinder head and the rod bearing?

I have the data sheet for these pistons.... they are VERY similar to pistons I routinely use in excess of 400 wheel hps on 4 cylinder applications.

 

This is very true, I just gave the dumbed down version cuz I was typing at 3 AM and high boost was the simplest way to get my point across before I passed out. Unfortunately gas here pretty much sucks no matter what, our best gas is your worst.

I'll post more pics when I get in.

 

Yeah I'll get more.

What applications are you using them in and how are your pistons made?

 

Thats a good one!

After further investigation it turns out that my compression tester had a bad seal or something internally and was not reading. My car merely burnt a coil and is back on the road. Im still considering sending my spare engine to ABF if i can get the scratch together to do so.

Do you think my engine is surviving because i run all aftermarket boost control ie boost controller wastegate BOV etc? My car has seen a ridiculous amount HIGH 29+ boost spikes in the process of trying all the different things on this car... Possibly lowering heat? My runs at like 165-180 all the time plus M7 oil cooler setup...

You believe that just the boost level did that? How much timing was being run? People think that timing equals HP and just keep goin...

 

1

 

No one has mentioned the well-documented and onerous N14 carbon build-up issue. One can easily envision a situation where a deposit within the combustion chamber near the cylinder wall causes a multiple flame-front (i.e., detonation) and the shock wave combined with boost pressure is enough to do this kind of damage. The carbon deposits would also have an insulating effect slowing the normal transfer of heat away from the combustion chamber into the head, raising temperatures and making the affected cylinder further susceptible to pre-ignition and detonation.

Couldn't this be a "smoking gun" (no pun intended) related to the DI carbon issue that has folks running around with SeaFoam and walnut shells in their pockets? The fact that these failures are purportedly observed in non-tuned engines too would seem to support the connection.

 

Mike what was the final max boost that car saw before failing? Do you know if it was running 93 octane? Im running 18.5 psi and (knock on wood) nothing, nada has happened, however i got my car tuned by a VERY reputable person and I’ve never heard of any of his tuned cars fail. IMO alot has to do with the Tuner and the Tune the car has.

 

FIRST... I didn't "stuff" the car into the tires... I merely "parked" the car close to the wall so I could get a better view on the opposite side.

I think back then I was running about 20psi.


Mark

 

Maybe the engine is still open and you can go take pics, since they told you it had skirt damage.

 

While a failure can be tune/tuner related...I do not think this is the case with these piston failures. A poor tune will kill a motor rather quickly...and the type of damaged caused is generally different than what you are seeing here. Like Mike said, the motor showed very little wear...other than the broken side of the piston.

Your motor is not going to fail just because you are running 18+ psi...it takes time. I was tuned for over two years before I saw failure. I've said it before...as more time goes by you WILL start seeing more of this.

 

Ok I got some more pics, just took awhile to re size all them.


In these 2 photos the large gap below and behind the ring lands can be seen. This was what I had mentioned before as being a very weak point in the piston.





The skirt in the pic above shows very little wear, along with the cylinder wall and bearing below





The crown is pretty messy, but 50k and no catch can it's not unexpected.



-MIKE

 

It was seeing 20 psi pretty regularly.

It's irrelevant for me to name a singular person as every tuner with R56 maps out right now has blown one or 2 up already, guaranteed. It's just the inevitable out come of testing new territory. Some ones engine always takes it for the team.

Unfortunately there is still more to be learned and an agreed stress limit has not been found. However more MCS's seem to be running longer with less issues at moderate boost level then those exceeding 19 PSI.

 

This is a more then valid point. As I stated before the N14 is not with out it's own faults. However I have seen this issue on relatively new engines too. Unfortunately those went to the dealer so images are hard to come by.

Some one else brought it up, but MINI essentially did what many are trying now. They ran high boost level on the 10:4 C/R MCS engine when testing the JCW turbo. This failed countless times and the end result was they had to use different pistons with lower C/R.

 

So if HEAT is a KILLER and I am a believer that it is then is it time we tried to improve fuel conditions and reduce heat with a water/meth kit on the turbo Mini's ?

 

Mike, are you still suggesting that the blown engine you have is still caused by over boost from the tune as implied by your initial post.

Some posters seem to want to also imply that it is a design defect and not over boost related.

Any opinions.

 

Start this out with MCS's are what we are talking about here.

CBS, WOW i am really surprised at that comment. Its not like we just said "Hey everyone just try this out and see what happens". We were tuning on these for a long long time before you all knew about it. Besides our 4 shop cars over that period of time that we tuned on, we did do a few customer cars to help with proving tuning. We have numerous customers that do track days and autocross events on maps we don't supply to normal customers and don't have issues. What we send to customers we feel is very safe. There are enough smart customers out there(you being one of them) that know what knock is and i have NEVER had a call from a customer saying that their map is knocking. Of the hundreds of customer logs i have looked through, i have NEVER seen knock.

For sure we have heard of failures, but we have also heard of failures on stock cars or cars with bolt ons and no tunes. Even a good customer of ours was driving down freeway at cruise speeds and had a piston ring fail. Its 100% expected to have a few failures here and there, but there is always a huge amount of variables to why they fail. Wrong map, wrong fuel, bad gas, fuel pump failure or loss of pressure, over revved, carbon build up, massive crank case blow by, bad injector. All those things are 100% real issues i have heard and seen, and even heard and seen at the dealer level.

Also keep in mind there is a 20psi limit in place anyway(which we "were" trying to remove). So an MCS might bump just a bit over at low RPM, but it will not run 20psi or more for more than a split second. During these short overboost times(even up to 24psi when tuning) the engines are super happy and tuned such that the timing is very safe so no knock occurs. During our tuning the only time we ever had audiable knock was when the dealer gave us the car back with 90octane fuel! We have had a few STage 3 MCS guys with boost cut happening, and we have taken care of those as we hear about it.

Below shows the Billet turbo running right at that 20psi limit (which it was very happy and had lots more power to go) and the dark green line is what a Stage 3 car runs. You can see that its pretty solid at 18psi and drops at redline. Again, we feel this is very safe. 91octane guys drop a couple PSI from the 2700-3800 range ignition timing.




Define Dangerous? Why is 22psi dangerous? AFR, timing and octane are the things i would be concerned with. Like we have said many times before, our maps are not maxed out at all! In fact every single map we tuned on the dyno was taken to a point, then we turned down boost, removed some timing and richened up the AFR a little to allow custom tuners to be able to get more out of them at a later date.

Many times a week, we get calls from customers just wanting to run the Stage 3 maps just to run them to see what they are missing out on. So how do we know this guy wasn't one who threw in the wrong map and went bang. Its a CA car so already running the 92oct version of his map (on accident or on purpose) means more boost and more timing, which is not good for crappy 91 fuel.

We are in a tough position, we could have just had one map for each car, and said thats what you get. This is just like other euro ECU tuners work. We could have done this and left it up to our custom tuners to take care of the rest. The problem is customer demand. Customers want special maps, custom this and custom that. And we felt that it was no problem to offer that (even though requires lots of work) and as we signed up more customer tuners, our customers would be drawn more to them anyway.

Maybe ABF will finally grab the AP tuning software and take over being THE CA approved AP tuner??

If ABF said a couple years back, you NEED TO DO PISTONS, you all would have said your nuts. BUt now since ABF has internals they can sell you, this may become the recommend thing over X amount of HP. I actually emailed them about this last week just because a couple customers wanted to do some crazy stuff. I think ABF is showing that MINI isn't using the best design for pistons, and or that the quality of the MINI pistons vary. I hope that i don't scare MINI customers to thinking their motors are all going to blow up or all the internals are crappy.

I see this is the natural progression of a tuner car. A car comes out, people make a few bolt ons, they get abused, ECU tuning comes out, people start to push the envelope, things break, people find the weak links, people fix them by upgrading internals, then a general rule is created for when its time to do internals. I think the Mini finally is to that point. But i really do think that the 18psi-20psi people are running is very very safe.

If there are customers that are concerned and want to run less boost, run the Stage 1 maps. These still make great power and you will have tons of fun with them.

 

The two are tied together...take poor design and run it outside of the opperating parameters it was designed for and you greatly open up the possibility of failure.

I'm no tuner...but isn't there more to the story on whether a motor can handle 20+ psi than just whether or not its knocking...?

You can have a good, safe AFR curve...keep timing in check, have no knock...but you are still increasing cylinder pressures dramatically higher than the components were designed for. I did not have knock...I datalogged constantly too, I was actually datalogging when the piston failed, it was rather undramatic. No CEL's even....the only way I knew something was up was it sounded like an STi at idle...lol (and the obvious lack of compression).

I know you're trying to defend your product and tuning, but it's inevitable that there are going to be more failures surfacing on people running higher boost...regardless of who tuned it. I think it can be said that's a fact. The question now lies in the detail though...what can truly be considered "safe" (I think nothing can...seeing as stock cars have had issues too) & what exactly about the design is the weak point and how can it be improved.

 

For sure we are defending our parts and mapping as its implied that its ALTA's maps causing the issue. But you are right to a point. Cylinder pressures can break things, but a small piston like this 20psi even with 10.5 static (not dynamic, which is way way more important) doens't have that high of pressure to start with (indicating weak pistons potentially). Also ignition timing is a HUGE factor in cylinder pressures. We still feel that we run it pretty safe. For instance, we can bump up timing 3-4 degrees and it still runs fine without much change to engine noise or knock. The problem is that there is little TQ gained doing this, so we leave it somewhat conservative. Good tuners will tune a car to the best mean torque where you find what timing gives you the best increase in power with little change. When those changes start to gain very little, you stop or back it off. We actually are a little under this on all the maps.

ThumperMCS, I would love to see your data when this happened. I am sure you have looked this over or RMW(as i see its an RMW tune??) but let me see what you have.

 

The stock piston is made by mahle with similar metallurgy to what is used in late model VAG applications. I have the factory data sheet of the stock pistons and rod for the 2009 model year. If your interested in taking a look, I can dig it up for you.

No super apparent visual signs of know... but with a piston that carboned up, it would be hard to tell if there were any pitting.

 

I completely agree. On the r56 engine, especially on stock turbo there is a fair amount of room between mbt and knock. Interestingly on high hp applications in that last 2-3 degree where there is very little power gains, there is a fairly large reduction in EGT. Kind of in line with what you would expect on an older less efficient engine.

 

Water/meth injection is certainly effective at controlling detonation, I'm sure your all aware of the benefits of reducing air intake charge temperatures, I don't think we need to discuss that here in this thread.

However you all must be aware that what we see on our gauges monitoring water and oil temp, is not how hot our engines are actually running, those are simply the fluid temps!

Engine core and cylinder head temps are way different, and anybody that monitors EGT's and cylinder firing temps will know what I'm talking about.

So anybody increasing power, no matter how you go about this, you are introducing extra unwanted uncontrollable HEAT, and unless you've taken necessary precautionary steps to combat this, then your asking for trouble and eventually it will and here in this thread is proof, end in tears and lots of $$$ of which you should have spent as a preventative insurance in the first place!

I'm sorry if I seem to be ranting on, maybe I am, as I am frustrated with the way folks go about looking to blame anyone and everyone including components, tunes, tuners, when in reality you should be looking directly at yourselves, as you yourself are the one to blame.

I really can't see why when you have a limited budget, you want to even see what stock components limits are, and then moan like a ***** when it all goes wrong, if you want power go about it correctly and build for it, remembering that POWER = HEAT and uncontrolled HEAT will kill your engine.