[myke354]

Originally Posted by mycoupe

Just some thoughts here on what you stated...

1. Why would running a different coil and burning the fuel better change the fact that it is di and the carbon is built up on the intake side of the valve not on the combustion side? The better solution would be to run a second set of fuel injectors in a spacer between the manifold and head to "wash" them clean.

check my other comments as i answered that for someone else

2. Are you assuming he wants more compression? Because I am pretty sure he stated that he was switching to a lower compression like the Alpina so that he can run more boost and therefore make more reliable and safe power.

i know he said he wanted lower compression and there is nothing wrong with that.. just remember please how small the turbos are and how much boost he was running 14-15psi and at 17psi we are over boosting our turbos..

3. Our blocks don't need sleeved because they have AluSil sleeves already.

this i did not know so thank u for letting me know

4. The piston has ideal flame travel. Since the motor is DI, the fuel and spark happen directly above the center of the piston maximizing the force it creates by pushing the piston straight down, unlike an FI motor.

now on this i dont think we will see eye 2 eye as i look at these pistons and all i see dished piston that looks more like a bowl.. but i am going to show these pics to a engine builder i work with and see what he says

5. Not trying to bust your balls, but the answers and reasons to most of what you asked or said you would have done is already covered in either his first post, or his subsequent. Hope this helps you out a bit since he hasn't responded!

i know ur not busting my balls and i thank you for ur feed back .. to me thats what forums are about

Originally Posted by maxnix

Could you please explain how this would prevent carbon accretion on the valve stems and the intake side of the valves?

ok if i am worng please let me know Carbon is a direct result of the fuel air mixture burning in the combustion chamber.. there for by adding a stronger spark would in most cases burn more of the fuel witch in the long run would make less carbon...

[Black Sheep]

Nice

[NTTY]

Originally Posted by E92Fan

Hi Ian

Yes, to remove the engine easily you have to remove the entire front assembly. You can take the engine out of the top, but it's a lot more hassle and takes longer. Far easier to drop the engine and gearbox out together from underneath the car.

The ZF gearbox software hasn't been written specifically for this car, but it is based on the Alpina software parameters with a couple of little modifications to better suit the torque delivery of my car.

Works probably won't be completed till after Christmas, if we're being realistic.

Amazing post, thank you for sharing!
Who did the modification of your software gearbox? What are the possible modifications?
Thank you!

[Richbot]

Prolonged high rpm operation is hard on any engine no matter how well it's maintained, that's why even nearly-stock engines that are well known to be overbuilt from the factory like the naturally aspirated BP in my old Spec Miata had to be rebuilt about every 40 track hours to maintain good leakdown and dyno results. The carbon buildup seems like a separate issue from the track use here...

[scheherazade]

Was the cylinder sleeve scored all around evenly?
Or was it scored mostly on the side opposite of the conrod/crank joint during down-stroke?

I expect a little bit of scoring, as things aren't perfect.
Every startup when oil pressure is low should contribute a little bit, and build up over time.
Was the crank scoring simply visible (as in still flat, but texture changed so light reflects differently), or was the scoring deep (grooved)?

-scheherazade

[Yes2m3cs]

Tony,

Thanks for taking the time to post all of that good info and pics! Unfortunately my wife decided to dump her 09 Cooper S turbo due to excessive carbon buildup

I traded my 08 135i at 46k due to fears of the same crap happening to mine.

I hope the engineers can do something about this DI Carbon crap soon because all the manufacturers are moving to DI.

I think we bought two of the last port injected cars left

Looking forward to your follow up results

Good Luck

Brian

[T1T2GRE]

After reading through all this I can't help but second think my decision to go for the 1SMC. Crap.

[MJR63]

I got a brand new 2011 335 with the N55 motor and after reading this thread I'm a little concerned. I'm a big fan of frequent oil changes and using synthetic motor oil. What does everyone in the US like to use? Mobil 1?

[SLEEPYDUB]

I was directed to this thread by Terry because im having idle problems and smoking problems whenever i decelerate. I also am consuming about a quart of oil every 1000 miles or so.

Tony, do you think that my problem could be similar to yours? A clogged up PCV system, or bad carbon build up on the valves? Im trying to pin point the problem and fix it, but BMW isnt helping me at all.

[Penn999]

Originally Posted by MJR63

I got a brand new 2011 335 with the N55 motor and after reading this thread I'm a little concerned. I'm a big fan of frequent oil changes and using synthetic motor oil. What does everyone in the US like to use? Mobil 1?

Motul, just made the switch.

[Penn999]

Originally Posted by SLEEPYDUB

I was directed to this thread by Terry because im having idle problems and smoking problems whenever i decelerate. I also am consuming about a quart of oil every 1000 miles or so.

Tony, do you think that my problem could be similar to yours? A clogged up PCV system, or bad carbon build up on the valves? Im trying to pin point the problem and fix it, but BMW isnt helping me at all.

Sounds like PCV, sorry to hear that man. Must be that big tom fmic not keeping IAT's down. JK man, BT and I were having a debate about fmic's and he directed me to your logs.

[SLEEPYDUB]

Originally Posted by Penn999

Sounds like PCV, sorry to hear that man. Must be that big tom fmic not keeping IAT's down. JK man, BT and I were having a debate about fmic's and he directed me to your logs.

logs speak for themselves. i did unbiased runs and that IC setup is tryly amazing.

Im hoping its just PCV. My problem is I cant get the dealer to replace it!!! Even under warranty! FML

[Penn999]

Originally Posted by SLEEPYDUB

logs speak for themselves. i did unbiased runs and that IC setup is tryly amazing.

Im hoping its just PCV. My problem is I cant get the dealer to replace it!!! Even under warranty! FML

They can be a pain to work with, thats why I have preached to stick to one SA and one tech, they will look out for you if you establish a good relationship. They let me borrow a brand new 2011 with 0 miles on it bc they were installing my 2nd oil cooler, occ, and fmic.(they are generally only allowed to give a loaner if its warranty work btw) tip um both and you wont believe how much things will turn your way.
On the fmic comment, I wish you had done a little more testing in higher temps. Numbers wont be as favorable, im not saying that its not a good IC but I think a more rigorous test will yield some diff. results. Most of us rarely see those cold of temps year round. Have you ever done the same test at 85+ degree ambients?

[SLEEPYDUB]

Originally Posted by Penn999

They can be a pain to work with, thats why I have preached to stick to one SA and one tech, they will look out for you if you establish a good relationship. They let me borrow a brand new 2011 with 0 miles on it bc they were installing my 2nd oil cooler, occ, and fmic.(they are generally only allowed to give a loaner if its warranty work btw) tip um both and you wont believe how much things will turn your way.
On the fmic comment, I wish you had done a little more testing in higher temps. Numbers wont be as favorable, im not saying that its not a good IC but I think a more rigorous test will yield some diff. results. Most of us rarely see those cold of temps year round. Have you ever done the same test at 85+ degree ambients?

My SA's are dicks at this dealership, i wouldnt tip them a nickel.
I didnt have the IC on long before I had to take it off for maintenance.

[pittyinSC]

I know that after seeing this many of you are gonna be worried about carbon buildup. Aside from the preventive measures that have been stated earlier in the thread, I would suggest using Seafoam right into the intake, drive the car HARD, then do an oil change. This will remove any of that buildup and will save anyone the hassle of having to pay big $$$ for a fix. Spend the 13$ on Seafoam and potentially be worry free.

[mycoupe]

Originally Posted by myke354

ok if i am worng please let me know Carbon is a direct result of the fuel air mixture burning in the combustion chamber.. there for by adding a stronger spark would in most cases burn more of the fuel witch in the long run would make less carbon...

I see what you are saying here, but that would pertain more to egr passageways, and not to the intake valve stems and backs of the valves. The combustion chambers and valve faces themselves are doing just fine on these motors. What is happening is that there is a lot of oil blow by in these motors from the pcv system that gets routed back into the intake tract leaving lots of oily residue in the intercooler, charge pipe, intake manifold, and then the bit that's making it's way back into the motor via the intake ports and valves is getting heated up and sticking to and coking up on the back of the valves, the valve stems and the intake plenums themselves. Pm me if you need me to explain it better, I might be able to google out a picture or something to help with the mental image.
Jeff

[Penn999]

Originally Posted by SLEEPYDUB

My SA's are dicks at this dealership, i wouldnt tip them a nickel.
I didnt have the IC on long before I had to take it off for maintenance.

Im sorry to hear that, I do have to say that it took me a while to find one that was cool. It is labeled on my receipt, "customer states that he wants only L50(my tech) to work on his car." Never had any problems after I got that established. Actually they do all my performance mods on my car.

[m6pwr]

Originally Posted by MJR63

I got a brand new 2011 335 with the N55 motor and after reading this thread I'm a little concerned. I'm a big fan of frequent oil changes and using synthetic motor oil. What does everyone in the US like to use? Mobil 1?

You might consider a new formulation put together by Shell/Pennzoil called Pennzoil Ultra Euro 5w40. Its claimed forte is ability to clean and prevent deposits, low volatility, and is a PAO base stock and advertised for di engines. It meets BMW LL-01, ACEA A3B3 etc. Its the spec oil for Ferrari in the U.S. and is also used in the Risi Ferrari 430 in ALMS and LeMans endurance racing. Only drawback (unless you want to purchase at a Ferrari dealership) is you have to order online from Pennzoil (about $50 case of 6 qts), tho they give you free shipping (allow about 10 days before arrival). I think Amazon.com will start to carry too. You can find out more about it at Pennzoil.com. Click on the press releases at bottom of page; go to contact us (strangely enough) to find the technical data sheet. I have high hopes for this oil in a street N54/55.

Two other PAO grp IV oils that meet BMW LL-01 spec are:

Castrol Syntec Euro Formula 0w30 (the "German Castrol") readily available at Auto Zone, Pep Boys ,etc. Its what I'm using now. UOAs show its hanging in there, but barely. Uncharacteristically shearing back quite a bit (fortunately its a very thick 30 wt out of the bottle).

Another possibility is Motul 8100 X-Max 5w40 available online at Turner Motorsports. A relatively new formulation, but I think overpriced for what you get in this formulation (Motul 300V is a different story); around $10 per litre.

And if you are really concerned, as you say you are, do used oil analyses to establish oil condition in your N55 and to figure out how long you can go between oil changes before the oil is mauled to death by di and turbo. Focus on viscosity at 100 C, flash point, and% fuel dilution in the UOA reports. And maybe share the results on this forum.

Blackstone Labs and Dyson Analysis are two labs that I'm most familiar with. About $22 and $5O respectively for a UOA. Blackstone is very popular but is somewhat weak on the flash point/fuel dilution part of testing the sample. Dyson will give a more accurate picture on that part of the report. For some extra bucks, you can get a tribologist (Terry Dyson) to interpret the report. Be anal!

[E92Fan]

Originally Posted by jaybird124

Tony,

As you've stated piston swelling due to heat under high load has been the primary cause of the scoring.
Do you see any evidence with your tear down that supports the concerns people have about fuel dilution caused by DI?

Doesn't seem to be any fuel dilution evident, although it is hard to say for sure after the tear down...

Originally Posted by AstonMartin

Aside from those deep scores, sidewalls seem like they experienced some serious wall wash.

What tune have you been running?

The original tune was from a company in the UK called DMS. Was very good at the time, but after developing and modifying the car more their tuning capabilities didn't seem as comprehensive and rock solid as I was hoping. Changed to a custom map from a great race shop in Germany and would keep using them had it not been for the need to see how Procede would work with a fully upgraded engine.

Currently using Procede...

Originally Posted by voltron1011

Wow, I'm really starting to rethink whether or not I want to order a E92 335i.
I'm a regular 'Ring Runner' myself and I think I might be better off springing the extra 10 grand for an M3. It's neither FI nor DI.

Honestly, I wouldn't order a 335i for use on the 'Ring if you are a dedicated 'Ringer and know how to drive properly there. It depends how many laps you will be doing, and how fast you'll be driving. The N54 engine needs so much modification to make it reliable and suitable for the track. You're better off springing the extra 10k for an M3 if 'Ringing is your main aim for the car.

Having said that, Marcel (Alpina_B3_Lux) has a fully modified 335i (everything except engine internals) with an all-aluminium radiator as well and he does maybe 50 laps of the 'Ring a year and his car seems fine so far.

Originally Posted by myke354

tony i know u dont know me but i would love to add some of my .02 cents..

first off a good way a way to stop that carbon from building up would be to run a aftermarket coil per cylinder. this would allow you to burn fuel better there for less carbon would build you would gain a few mpg's and make a few more horses..

second: why not go to a flat face valve to add back some of the compression??

i have to admit i am so glad someone has had the balls to tear down this motor so on the u have my respect .. i know i have been waiting for it to blow before i tore mine down.

to be honest i would have went a different way with the rebuild and i would have had the block sleeved and i would have ran with a 10.1 piston and and i would of liked to see a piston that would give better flame travel..

did u have the piston coated with teflon and ceramic??
i dont know if u looked into it but i know for a fact that having the combustion chamber , valves and piston top ceramic coated has shown to make more power last longer and on turbo cars spool turbos faster cause u push more hot air out to the turbo and have less heat soak..
and have you looked into having the rods, skirts and bearings WPC treated???

i wish you the best of luck with ur rebuild

When you say aftermarket coil, do you mean an extra injector? Have looked into adding extra injectors, but I would then have to change the BMW ECU and use a KMS or Motec system if I wanted it to run properly.

I have to decide ultimately what this car is going to be used for. My 335i is a road car first and foremost, although it has done maybe 500 laps of the 'Ring! If I keep it as a road car, then I won't go to the extreme of a KMS or Motec ECU. If I wanted it as a dedicated 'Ring car, then yes I'd make the N54 race-ready with changes to the fuelling system, the ECU, fabricate a dry sump system for the engine, and then I'd strip out the car completely.

The fact I'm in the process of building another dedicated 'Ring car (with an E46 M3 race engine in a 1 series hatchback body) means that I'm less inclined to go the whole way and make the N54 engine race-ready.


My rebuild spec of the N54 engine is designed so it's more reliable under boost than the standard engine. I want a lower-compression (9.5:1) rather than an almost-normal 10.1:1 as you suggest. I am sure the block is strong enough not to require sleeving, and with the new piston design I don't think I will suffer from piston over-growth.

And yes, the pistons are teflon and ceramic coated

Originally Posted by m6pwr

I'm coming in to this thread a bit late, but I do have an interest (I've got an N54 in an '09 Z4). And I have a couple of thoughts that might be of interest re oil and the N54.

The problems associated with direct injection engines (not just the N54 but apparently all di engines) are fairly well known by now. There have been SAE papers on the subject and research is underway by at least one piston ring manufacturer to try to address these problems. And on the BITOG (Bob Is The Oil Guy) forum, a lubricants engineer who regularly attends the 24 Hrs of the Nurburgring race, and meets with race and lubricants engineers there, recently posted rather cryptically that the topic of the hour at the last race was the problems associated with direct injection (which is becoming pretty much the standard in engine design). When I sent him a pm to ask for more information all he would say is that the problems would have to be solved by the engine mfrs, not the lube mfrs. Nice.

The problem is fuel dilution. DI engines operate on much, much higher injection pressures than the "old" port injection engines. In the N54, fuel is injected at 1200-1700 psi, compared to about 45-75 psi in a port injected engine! Pretty amazing. That means higher blow by of fuel past the rings and more "wash down" of the oil film on cylinder walls. The fuel dilution in turn causes two major problems with the oil: viscosity loss (shear back) and significant lowering of the flash point of the oil (more oil vapors form to be sucked up by the CCV system and possibly form deposits in the intake track and valves). The extra heat generated by turbo charging can exacerbate these problems. There is one study I have read about that indicates if the fuel dilution gets bad enough, it can dissolve the tribological film laid down by the anti wear additive ZDDP. Sounds like Doomsday. You have to wonder why aren't BMWs with the N54 disintegrating all over the place. Must be good metallurgy in those motors.

As owners we can't do much about the design of the N54 but we can focus on the oil. I'm not going to recommend any specific oil, but I can say if your concerned like me you probably ought to change the engine oil frequently and do used oil analysis (UOA) at a good lab (flash point measured under ASTM 93/closed cup, and % fuel dilution measured by gas chromatograph) to figure out the oil change interval (OCI). There are no absolute standards or pass/fail marks for these indicators. Each lab seems to have their own standards and I sometimes wonder if some labs have any pass/fail limits at all. I have seen N54 UOAs posted on BITOG where the oil (the BMW 5w30 factory fill) has sheared back to a 20 wt (in as little as 1500 miles OCI) and no warning or negative comment given by the lab at all. In my opinion an oil should never shear back out of grade; and I'd start to be concerned if % fuel dilution exceeds 2%, and flash point goes much below 375 degrees F. I am frankly wary of BMW's 5w30 oil, and the factory OCI of approx 15000 miles is absurd in a motor like the N54. I would use the best grade synthetic (PAO or ester base stock) I could find and afford, preferably one that meets BMW's LL-01 standard and is in the viscosity range recommended for the N54: 5w30, 5w40, 0w30, or 0w40. And I would do regular UOAs until I could figure out how the oil is performing in my particular style of driving. If your N54 is out of warranty, or you don't care about warranty questions, you can go farther afield. Some folks in the lubricants industry think that part of the answer to di is vegetable-based motor oils, or bio-syns, which appear to stand up to fuel dilution better than conventional synthetics. Others mock these lubes as Mazzola/Canola oils. I do know that Fuchs (a leader in synthetic oils since the 1930s) has recently come out with a bio-syn series of synthetics. Unfortunately, I can't remember the name (Fuchs motor oils aren't available in the U.S.).

Tony, when you get your new rat motor finished you might want to try to communicate with John Rowland, the head chemist with Fuchs, through your Fuchs distributor. He is an avid racer and can be quite forthcoming with advice for individuals using his oils. He may be able to give you some ideas on the best oil for your application.

Sorry for taking so much band width. Hope I didn't go over stuff you already know. By the way, I think the N54 is a dynamite motor and I knew all about the di problems (and the HPFP) before I bought the Z4.

Thanks for the great info above. This will help a lot of people on the forum

I have already been in contact with John at Fuchs as I know them well from Nurburgring races. I have been using the Fuchs ProS 5W-40 ester-based synthetic oil for the last 40,000 miles. I personally don't subscribe to BMWs insistence that the Castrol 0W-30 or 5W-30 is suitable in the N54 engine with oil changes potentially only every 18,000 miles. The viscosity loss suffered by the Castrol Edge oil is well known in the racing fraternity here and given the N54 runs hot anyway, it staggers me that not more people have switched to a more performance-oriented oil.

Despite all the problems, I also think the N54 is a dynamite engine but not if you're subjecting it to the high-stresses and operating temperatures that a race track induces.

[E92Fan]

Originally Posted by maxnix

Well, geometric compression ratio is not as important as Mean Effective Pressure, which in turn is a function on many other engine operating parameters including rpm.

But in any case, it is usually the case that a lower CR will require a higher flow (more pressure) to reach the same MEP as the same engine with a higher CR will achieve the same MEP with less flow, and thus requires less pressure.

It is interesting BMW chose and open deck design for a turbo engine. Presuming the OEM pistons are forged?

Yes, OEM pistons are forged, and made by Mahle

Originally Posted by mycoupe

Just some thoughts here on what you stated...


2. Are you assuming he wants more compression? Because I am pretty sure he stated that he was switching to a lower compression like the Alpina so that he can run more boost and therefore make more reliable and safe power.

Exactly the reason why I'm going to a 9.5:1 compression ratio - more reliable at the same given boost level. I'm not looking to max out the boost pressures - I've been running 15/16psi for a long time now, and still want to run the same but at a lower compression ratio.

Originally Posted by NTTY

Amazing post, thank you for sharing!
Who did the modification of your software gearbox? What are the possible modifications?
Thank you!

The gearbox software was rewritten by ZF themselves and an engine tuner in Germany. Unfortunately it's not a commercially available software revision as it was done as a one-off as part of an exchange of services

Originally Posted by scheherazade

Was the cylinder sleeve scored all around evenly?
Or was it scored mostly on the side opposite of the conrod/crank joint during down-stroke?

I expect a little bit of scoring, as things aren't perfect.
Every startup when oil pressure is low should contribute a little bit, and build up over time.
Was the crank scoring simply visible (as in still flat, but texture changed so light reflects differently), or was the scoring deep (grooved)?

-scheherazade

Sleeve was scored all around fairly evenly. Was fairly grooved too

Originally Posted by SLEEPYDUB

I was directed to this thread by Terry because im having idle problems and smoking problems whenever i decelerate. I also am consuming about a quart of oil every 1000 miles or so.

Tony, do you think that my problem could be similar to yours? A clogged up PCV system, or bad carbon build up on the valves? Im trying to pin point the problem and fix it, but BMW isnt helping me at all.

The smoke when you decelerate is definitely something I suffered from - I suspected it was oil being drawn past the piston rings. The excessive oil consumption should also suggest this as well. A blocked PCV wouldn't explain the excessive oil consumption, although it might explain the lumpy idle.

BMW's stance is difficult - they won't look at the problem because they don't want to commit to such a large labour bill only to discover there's nothing wrong with the engine. I would suggest you approach your dealer and ask them to investigate - you'll probably have to agree to pay the labour, or a fixed portion of the labour, in the event that they discover there is nothing wrong with the engine. If there is something wrong, then BMW will cover the cost under the warranty.

At the very least you need to have a full inspection of the head to see the state of it

[enrita]

you can Probably run 18 psi on pump with 9,5 compression ratio and still have some headroom . Considering the quality of pistons you are putting in you should consider increasing boost since by lowering the compression you will loose some power at the same given boost pressure.

Pity the ZF software was a one off... would not mind flash mine this summer.

[E92Fan]

Originally Posted by enrita

you can Probably run 18 psi on pump with 9,5 compression ratio and still have some headroom . Considering the quality of pistons you are putting in you should consider increasing boost since by lowering the compression you will loose some power at the same given boost pressure.

Pity the ZF software was a one off... would not mind flash mine this summer.

I don't want to run 18psi, that's the thing. I'm not bothered about peak power or running the engine to its limits - just want to run a nice safe 500bhp (flywheel)

I can get the ZF software done for you, but it will cost a lot...! About 3000 Euros probably for ZFs labour time