[npb]

will these help at all??

matrix power and specs for MHI turbo's

http://www.google.com/translate?u=ht...&hl=en&ie=UTF8

click "automobile" then "turbocharger" and scroll to bottom.

[2007_E93]

Does ANYONE else find this a bit suspect that the "TUNE" is the cause for all of this $$$ reapirs on whoever's car?

If I owned that car and I suspected that the "tune" I had was the main culprit then I would be on here in a red hot second posting all about it. Afterall, BMW would have voided this guys warranty FOR SURE and this driver would have NOTHING to lose by being vocal about his thoughts.

This is not to disrespect Hotrod or the value of his information and possible damage to our cars by the mods we do,...just that I don't think you can claim any ONE mod caused this level of catastrophic failure. Someone who mods his car to that level probably drives it quite hard and MAY not have followed all the recommended guidelines for UT values and other such things. I could be wrong there but I think we can NOT come to any conclusions on the cause of this guy's failure without hearing more details or even from the actual driver himself. He is very likely an E90 POST member....where is he? We also don't know for sure which tune it was.

Just my 0.02

[Orb]

Originally Posted by scalbert

I would agree, pushing these turbos to 18 - 19 PSI at redline would not be safe. But what is unsure is what is truly safe for the turbos. My only point is that if they can hold that pressure at redline, being nearly 25% lower may not yield implosion. Will it accelerate bearing wear, I would certainly agree.

Once again, we are at a point where there are unknowns. Some stock snails will fail. While some run hard will last 50k - 100k. After a while we will see that there is no guarantee but will have an idea of what occurs and when. Until then, we should enjoy our choices and focus on ourselves and not about what may or may not happen to our brethren.

I don’t think we have lot to disagree on. The only thing I pointed out is there enough evidence here to backup that the turbo efficiency is starting to slide around 14 PSI +/- 0.5. These air intakes and after market filters don’t magically make 2.5x the power with just 1 PSI boost change. Even Shiv tested filters and said there little improvement at 13.5 PSI but a major improvement at 14.5 PSI. It suggests the gains are riding on the tail of compressor efficiency. If would seem it is time to change the strategy for more boosts and go for a full attack on pressure drop. There are many way to make more power and minimize risk and putting an IC would be the first thing to help as this can bring boost at the turbo down by 1.3 PSI for a 14.5 tune. It is an insurance policy that may be worth it.

Orb

[trueblue]

Here is the compressor map for the MHI TD03 VG turbo with the factory boost settings/flow vs Dinan. If anyone has a log of the boost pattern for other tunes just sent it to me an I can do the calculation and superimpose the result on the graph. Notice the boost taper when the choke line is hit, this is done both by stock ecu as well as Dinan.

[hotrod182]

Originally Posted by 2007_E93

Does ANYONE else find this a bit suspect that the "TUNE" is the cause for all of this $$$ reapirs on whoever's car?

If I owned that car and I suspected that the "tune" I had was the main culprit then I would be on here in a red hot second posting all about it. Afterall, BMW would have voided this guys warranty FOR SURE and this driver would have NOTHING to lose by being vocal about his thoughts.

This is not to disrespect Hotrod or the value of his information and possible damage to our cars by the mods we do,...just that I don't think you can claim any ONE mod caused this level of catastrophic failure. Someone who mods his car to that level probably drives it quite hard and MAY not have followed all the recommended guidelines for UT values and other such things. I could be wrong there but I think we can NOT come to any conclusions on the cause of this guy's failure without hearing more details or even from the actual driver himself. He is very likely an E90 POST member....where is he? We also don't know for sure which tune it was.

Just my 0.02

The owner of the car has already been commenting earlier in this thread. I am local to all of this, I know the tech, and was there when he pulled the turbos. The owner also saw all the turbo damage.The owner does have access to pictures and video of his turbos when they were removed. He can decide whether or not he wants them posted. He also saw that there were no signs of packing peanuts or loose nuts etc, or damage to the face of the compressor vanes. Just complete bearing failure and impeller/housing contact.

[Orb]

Originally Posted by hotrod182

The owner of the car has already been commenting earlier in this thread. I know the tech, and was there when he pulled the turbos. The owner also saw all the turbo damage.The owner does have access to pictures and video of his turbos when they were removed. He can decide whether or not he wants them posted. He also saw that there were no signs of packing peanuts or loose nuts etc, or damage to the face of the compressor vanes. Just complete bearing failure and impeller/housing contact.

Was that one or both turbos that the damage was on?

I know it is implied but i want to make sure...thanks

Orb

[trueblue]

Originally Posted by Orb

Is this a joke?

http://waterbabiesbikini.com/forum/a...2&d=1209440466

Orb

My apologies, i linked to an image that requires login. The link has been changed to imageshack, hopefully it will work now.

[aaronb]

Originally Posted by E82tt6

If you can point out anywhere that Dinan has said otherwise, I'm all ears.

Such as increasing water pump speed at boost and removing top-speed limiter?

Originally Posted by E82tt6

As for how Dinan does or doesn't engineer their products, I'm SURE if they did anything close to what I suggested, they'd be real quick to let you know about it. I HIGHLY doubt that they did. It doesn't make sense for them to do that, when they could just do what they did. Crank an extra 40rwhp out of the motor (well within BMW's tolerances) and call it a day.

They talk aplenty about the longevity issues with upping boost on an N54 in that whitepaper/pressrelease they did:
http://www.e90post.com/forums/showthread.php?t=100630

I never saw anything from Shiv or Terry about the rigidness of the block, or concerns about snapping cranks. Did Shiv or Terry ever put a motor on an engine dyno to measure bhp? Do they even have an engine dyno? I'm sure if Dinan is going to go through the trouble of pulling a motor for an engine dyno, they might as well take a peak at some other stuff...

Don't forget Dinan is also a reflash, not a piggy... what kind of resources do you think it took to RE or bribe just so they could do that flash? What else did they learn about the OEM software in the process?

I understand Dinan is perhaps marketing to people's fears. I'm pretty cynical when it comes to that kind of stuff.

I also see the fact that Dinan is backing up it's claims with a warranty and that costs money. Even if they don't increase the failure rate, they still have to take the financial burden to cope with bad snails from the factory that BMW will no longer honor the warranty for.

Bottom line is when Shiv's 335 finally needs a $15k turbo job from the flogging his $1500 box did it's ok. He'll drive to work in the Gallardo. When my 335 cracks a snail, well, I've got a vespa....

In case you can't tell, I'm partial to the dinan tune. All I'm trying to do is convey my opinion and provide the reasoning for it. Folks don't have to agree, that's certainly within their right. I enjoy discussing this, and am not trying to just stir the pot.

[m3rxn]

Dang thanks for the heads up hotrod! I'm glad I only have the SSTT and BMS filter..perfect combo for the street IMHO.. gotta admit the packing peanut theory is pretty .

[M4TW]

Originally Posted by Orb

I don’t think we have lot to disagree on. The only thing I pointed out is there enough evidence here to backup that the turbo efficiency is starting to slide around 14 PSI +/- 0.5. These air intakes and after market filters don’t magically make 2.5x the power with just 1 PSI boost change. Even Shiv tested filters and said there little improvement at 13.5 PSI but a major improvement at 14.5 PSI. It suggests the gains are riding on the tail of compressor efficiency. If would seem it is time to change the strategy for more boosts and go for a full attack on pressure drop. There are many way to make more power and minimize risk and putting an IC would be the first thing to help as this can bring boost at the turbo down by 1.3 PSI for a 14.5 tune. It is an insurance policy that may be worth it.

Orb

Orb you seem to favour this strategy. And as we know Dinan is coming out soon with its stage II that takes advantage of a larger FMIC. In the meantime, I've been trying to read and learn about IC's from what I can look up on the net so that I can understand them better and make an informed decision about whether the upgrade works for me. I have a couple of questions for you that I hope you can answer (and pardon my ignorance in asking them):

1. IC effeciency seems to decline as ambient temperatures drop meaning there would be less benefit to upgrading on a cold day (with mother nature providing the cooler charge air). Does this upgrade really make more sense for those fortunate to live in warmer climates?

2. The provisional advertising from Dinan seems to be a signficant hp increase over stage 1. This tells me that Dinan is not reducing boost (strain or wear on turbos) but is extracting more sauce from the boost it is already adding. Would you agree that it isn't truly an engine longevity enhancement?

Thanks in advance!

[npb]

Originally Posted by Sparkplug

1. IC effeciency seems to decline as ambient temperatures drop meaning there would be less benefit to upgrading on a cold day (with mother nature providing the cooler charge air). Does this upgrade really make more sense for those fortunate to live in warmer climates?

the 335 is my 3rd turbo'ed car (2004 a4 1.8t GIAC'd and 2005 STI)

IC + turbo efficiency DECREASES with HIGHER ambient temperatures. Did anyone notice their car performing poorer the last couple days in so cal due to higher temps???!

Colder air is DENSER, which holds more oxygen per cubic (__whatever__). More oxygen means more efficient and better combustion as well as cooler air's ability to cool the IC better...

[M4TW]

Originally Posted by npb

the 335 is my 3rd turbo'ed car (2004 a4 1.8t GIAC'd and 2005 STI)

IC + turbo efficiency DECREASES with HIGHER ambient temperatures. Did anyone notice their car performing poorer the last couple days in so cal due to higher temps???!

Colder air is DENSER, which holds more oxygen per cubic (__whatever__). More oxygen means more efficient and better combustion as well as cooler air's ability to cool the IC better...

Hey thanks for responding! I thought from what I read though that the IC's ability to make a difference (efficiency) diminishes as temperature goes down. In other words, it can't provide the same cooling delta with cooler air as it can with warmer air. I reealize that turbos work better with colder (i.e. denser) air and that is what an IC does - cool the charge air. I guess what I am saying is that a larger capacity IC may not provide as much bang for the buck when the ambient air is cold.

I guess I also wonder if there is diminishing returns on the engine's ability to take advantage of denser/colder air. My car didn't seem any more powerful when it was -30 C out than 0 C, but it is noticably more powerful when the temperatures are near freezing than when its hot (30 C).

[npb]

Originally Posted by Sparkplug

Hey thanks for responding! I thought from what I read though that the IC's ability to make a difference (efficiency) diminishes as temperature goes down. In other words, it can't provide the same cooling delta with cooler air as it can with warmer air. I reealize that turbos work better with colder (i.e. denser) air and that is what an IC does - cool the charge air. I guess what I am saying is that a larger capacity IC may not provide as much bang for the buck when the ambient air is cold.

I guess I also wonder if there is diminishing returns on the engine's ability to take advantage of denser/colder air. My car didn't seem any more powerful when it was -30 C out than 0 C, but it is noticably more powerful when the temperatures are near freezing than when its hot (30 C).

no problem...been discussing turbo's for at least 5 or 6 years now.
I believe that ambient temperature has a litttle bit more effect on engine and turbo performance than intercooler performance. (why do race cars have intakes OUTSIDE the engine bay??!) However, ambient temperature IS vital to the performance of both.

scenario (high ambient temp): less oxygen in one cubit foot of air vs. colder air. poorer combustion because of less oxygen. intercooler is not able to efficiently cool intake air because of the high ambient temperature, therefore, higher ambient intake temps all around.

scenario (low ambient temp): the denser, colder air contains more oxygen per cubic foot, therefore, better efficiency and combustion. the cooler air also cools the intercooler.

makes sense that you weren't able to distinguish performance between cold (0 and
super cold -30), but you WERE able to tell between 30c and the two colder temps.)
lesson: cold is good.
sorry if this is incoherent, kinda drunk.

add on:
someone used a graphic from howstuffworks that was good, but this is a good explanation about how turgo's work in a sytem and how ambient temps affect performance.

[OpenFlash]

Originally Posted by npb

sorry if this is incoherent, kinda drunk.

Best quote ever

[hellrotm]

Originally Posted by npb

no problem...been discussing turbo's for at least 5 or 6 years now.
I believe that ambient temperature has a litttle bit more effect on engine and turbo performance than intercooler performance. (why do race cars have intakes OUTSIDE the engine bay??!) However, ambient temperature IS vital to the performance of both.

scenario (high ambient temp): less oxygen in one cubit foot of air vs. colder air. poorer combustion because of less oxygen. intercooler is not able to efficiently cool intake air because of the high ambient temperature, therefore, higher ambient intake temps all around.

scenario (low ambient temp): the denser, colder air contains more oxygen per cubic foot, therefore, better efficiency and combustion. the cooler air also cools the intercooler.

makes sense that you weren't able to distinguish performance between cold (0 and
super cold -30), but you WERE able to tell between 30c and the two colder temps.)
lesson: cold is good.
sorry if this is incoherent, kinda drunk.

add on:
someone used a graphic from howstuffworks that was good, but this is a good explanation about how turgo's work in a sytem and how ambient temps affect performance.

This is why I have never liked the BMS intake setup. It just sucks in all the engine heat, heat soak. Eventhough it is going in the IC, it would makes sense that starting out with cooler air would have its benefits.

[KWA VaTech]

Originally Posted by Sparkplug

Hey thanks for responding! I thought from what I read though that the IC's ability to make a difference (efficiency) diminishes as temperature goes down. In other words, it can't provide the same cooling delta with cooler air as it can with warmer air. I reealize that turbos work better with colder (i.e. denser) air and that is what an IC does - cool the charge air. I guess what I am saying is that a larger capacity IC may not provide as much bang for the buck when the ambient air is cold.

I guess I also wonder if there is diminishing returns on the engine's ability to take advantage of denser/colder air. My car didn't seem any more powerful when it was -30 C out than 0 C, but it is noticably more powerful when the temperatures are near freezing than when its hot (30 C).

This might help out a little:
http://en.wikipedia.org/wiki/Carnot_cycle

note, half way down the page that Carnot cycle (best case) efficiency
= 1 - (Tcold/Thot)

I know I am really simplifying things and leaving out turbos ect.

But, it’s worth noting that the larger the delta T (the change in temperature between the engine and ambient), the more theoretically efficient the engine can be. All a bigger or better IC is doing is giving you a greater delta T (may also reduce delta pressure). All a cold air intake is doing is giving you a higher delta T (may also reduce delta pressure). Cold days help this as well and also have less water in the air (a good thing) but, then your tires don’t hook up as well and you have more air drag.

[scalbert]

Originally Posted by Orb

These air intakes and after market filters don’t magically make 2.5x the power with just 1 PSI boost change. Even Shiv tested filters and said there little improvement at 13.5 PSI but a major improvement at 14.5 PSI.


There are many way to make more power and minimize risk and putting an IC would be the first thing to help as this can bring boost at the turbo down by 1.3 PSI for a 14.5 tune.

I would read the intake benefit as a limitation in the flow rate to the turbo, not the turbo its self.

And very true, less pressure drop through a better IC would provide a margin of safety.

[Orb]

Originally Posted by scalbert

I would read the intake benefit as a limitation in the flow rate to the turbo, not the turbo its self.

I did consider that but the section and the relationship to length through the system and didn't find anything to support this and I did some calculations based on 500 to 700 CFM. We are only talking about 2-3 inches of water for the delta.

Orb

[scalbert]

Originally Posted by Orb

I did consider that but the section and the relationship to length through the system and didn't find anything to support this and I did some calculations based on 500 to 700 CFM. We are only talking about 2-3 inches of water for the delta.

Orb

The difficulty here is that flow calculation accounting for the lid ont he airbox would be nearly impossible. The flow dynamics may change in such a way, at a certain RPM, that the airbox is the culprit. Since that is what changes in an aftermarket intake, it is a somewhat safe assumption.

[Orb]

Originally Posted by scalbert

The difficulty here is that flow calculation accounting for the lid ont he airbox would be nearly impossible. The flow dynamics may change in such a way, at a certain RPM, that the airbox is the culprit. Since that is what changes in an aftermarket intake, it is a somewhat safe assumption.

I talked with Terry about the lid and he doubled the cross section with no measurable gains and this part is predictable within reason. The filter media will have the biggest influence by a long shot and would be impossible to make an assumption with this as it racially changes flow patterns based on the resistance and shape. The inlet just at the filter is unpredictable as well but can be converted in worst case for losses.

Obviously, I am making some assumption here and it is based on 10+ years as CFD experience doing this exact same thing we are looking at. We simply don’t have any long section creating major losses. I’m also only considering just a filter change as well which doesn’t add up.

Orb

[T Bone]

Wow the thread continues to evolve.

To the MODs, I suggest a sticky on how turbocharging systems work because there are some fundamental wrong assumptions in this thread.

More importantly, is the conclusion of this thread that a packing peanut caused the turbo failure and not the tune?? This is heart of the matter. If the answer is yes then let's move on.

[scalbert]

Originally Posted by Orb

Obviously, I am making some assumption here and it is based on 10+ years as CFD experience doing this exact same thing we are looking at. We simply don’t have any long section creating major losses. I’m also only considering just a filter change as well which doesn’t add up.

Have a few years under my belt as well in designing and implementing industrial control system which rely on flow for various functions.

Anyway, why not just yank off the airbox and put it on a flow bench.