[Rob@RBTurbo]

Can someone please do this for me..... Id like these demand lines/compressor pressure dots plotted on the 10T compressor map!! (see post 59 for charts)

Originally Posted by RobBeck

Would anyone with the time and appropriate skills be able to plot these exact demand lines at each pressure on this 10T compressor map?

The demand lines are the straight (nearly vertical) colored lines, and the boost per RPM are the little color'd circles. Please include the little keys on the upper left side of the map if at all possible.

These demand lines were derived from a 3.0L V6 at the VE's shown per 1k RPM and are probably reasonably similar to the N54... or at least better than nothing. Credits for this map belong to Jeff L. and http://www.stealth316.com/ .

Ive read that to convert the cfm to m 3/s, divide 2119 into cfm. I have also read that .1 m 3/s is equal to 211.888cfm. I dont know how to calculate either derivation myself. Both dont seem to be exact, but they are close enough to just get an idea of how far off the map we get at x,y,z PR's.

Thanks in advance to whoever is able to pull this off.

Rob

[Prince ///M]

Originally Posted by smdandb2

Like I said, I did not want to go in to this because someone always thinks they know better.

Translation: "People who think they know everything are a great annoyance to those of us who do."

[BavarianBullet]

Originally Posted by scottp999

and the fuel pump is not that expensive and should not be real hard DIY. So you can weigh all the work of returning to stock vs. the around $300 cost and labor to do it yourself. Sorry

I agree. Has anyone done a fuel pump on their own?

I'd guess it's not terribly hard to pull one off and put the other one on but I'd be interested in knowing if there are any special tools required or any unusual break-in procedures that if we missed them the pump might be toasted.

On topic: It seems we need to hook up some sort of air meter (MAF) to a stock airbox on a 335 and run a tune vs stock mode and see what the CFM drawn is.

It's been a while since I wrenched a lot on modded cars but I know pro-flow/pro-m sells MAFs with flow-bench cfm readings cross-referenced to MAF output voltages. I used these on mustangs in the past. If anyone had one, that could prove very useful with a basic datalogger, laptop and a 5V power source. You could measure cfm directly.

[HEY32G]

Originally Posted by Remonster

First off the stock horsepower rating is supposed to be 300 at the crank at 5,800RPM, based on dyno tests of the 335i and figuring typical drivetrain losses this engine is actually under rated and probably makes 330 or more horsepower at the crank.

If you're worried about damage to the car, as any sane person would be, and assuming you have the money why not get the Dinan tune? It's covered by their own warranty so you won't live in fear of some catastrophic failure. Compared to the other tunes available, Dinan's is fairly conservative and seems well suited for reliability and longevity while the other tuners seem to be after 1/4 mile times and power to the wheels now. The reliability of the N54 at increased boost is still an unknown since it has only been on the market for two years, it'll be after a few more years after people have dealt with blown turbos, cracked heads, broken rods etc. that we will really know what a safe boost level is.

Tuning is a gamble, it always has been. If you absolutely can not risk damaging your car maybe you should leave it stock, but as long as you understand that it COULD break and possibly cost a lot of money to fix and are able to deal with that possibility then there is a lot of power to be found in this engine.

Thank you!

[ar design]

Arent these the maps ASR claimed were unobtanium?

[smdandb2]

Originally Posted by ar design

Arent these the maps ASR claimed were unobtanium?

That is them! LOL

[asdflkijd]

whoa...

[e.n335]

Hi,

Well, I'm not any kind of engine or boosted applications engineer, but I'm an IT manager and engineer ( Open Systems, Networks, Application Development, PM ), so I'm used to think structured. I'm missing the point of the discussion here. All I would need is a safe boost / rpm curve respecting the 335i stock turbo capability, engine displacement, compression ratio and afr / fuel quality requirements. These are basic data for any kind of tune, IMO. Is it that hard to publish this kind of information ?

I question pressure drops above 1-1.5 PSI using aftermarket FMICs.

Let's get more concrete ...

Cheers,
Eugen

[john boxter]

someone was saying anything above 380 whp is pushing the engine past what it can hold i dont understand why? with downpipes intercooler dci jb3 (even map 5 (15psi) and meth you are probably past that already is that pushing the engine more that it can handle?

[e.n335]

Originally Posted by john boxter

someone was saying anything above 380 whp is pushing the engine past what it can hold i dont understand why? with downpipes intercooler dci jb3 (even map 5 (15psi) and meth you are probably past that already is that pushing the engine more that it can handle?

That is all I'm talking about. Producing safe power within the known, calculable and physical limits.

Someone has to close the gap between spreaded and well-known information and an appropriate recommendation / tune.

Cheers,
Eugen

[GTR-Dad]

Safe power level is something learned by experience. One of the other boards I frequent has a sticky where people report engine failures and the associated mods, boost level, and typical use.

In general, all else being equal, a well maintained engine driven hard, but not abused, will typically deliver some 'baseline' performance level for something approaching the life of the car. OEM tunes seek to minimize failures within the warranty period. Increasing the output of the engine will typically decrease its lifespan. Friction, wear, fatigue, and increased risk of breaking the weakest link all contribute to this.

Picture a graph showing peak power on the Y axis and engine life on the X axis. The OEM tune will show up as a point near the bottom right corner. (Lowish power, longish life) Turning up the boost will result in another data point a bit higher and to the left. If we had a statistically significant number of similarly maintained engines running a broad range of tunes we could connect the dots and have a pretty good idea of what an N54 can handle.

I suspect that most engines give up only a little life until engine loads (proportional to boost, power, torque) exceed a threshold we'll call 'safe' at which time life expectancy drops dramatically. I think that's what everyone would like to know.

As you can probably appreciate, this is not something done with a calculator or a spreadsheet. It requires experience and a bunch of interpretation. For example, if someone running 15 psi of boost advances their ignition a bit too much and the knock sensors don't tell the ECU about it (it happens!) and detonation knocks the ring lands off - is 15 psi 'unsafe'?

I'd love to see a sticky where members list their mods, tune, driving style (drag, circuit, spirited street driving etc) mileage at particular tune levels, and any problems they've experienced.

Dan

[enrita]

I have been pushing the limits since 20k miles with no issues both on jb3 and giac stage 2 flash.
If you take care of the car she will give you a lot back.

[STONEY_M5]

This is a very relevant post, it provides a lot of omportant information that I can not understand... But on a serious note you guys seem like you know your shit, but what sense does it make to argue with one another or say things like I dnt wanna post bcuz somebody always feel like they know everything... Instead accept the challenge and prove yourself right( it 's a $35,000+ investment that you are helping us/yourself with) and then you and other engineers can chime in and come up with the RIGHT answer and not the right ASSUMPTION... I know nothing about what you guys are saying but the more i read the more i learn...


P.S. The pressure drop from the turbo to the Intake Manifold is definetly going to be higher than .02 because of the resistance that is there from all of the piping and tubing, the length and diameter of the pipes and so forth...

I'm learning...

BTW Can't we all just get along!!!

[franzzz]

Great info !!!

tnx

[Insider]

Originally Posted by DMETune

Here's some compressor map data for the turbochargers on the x35 N54 vehicles.

From this we can gather that a pair of these turbos spinning at redline can produce ~1150 kg/hr of airflow, which translates into ~42.25 lb/min.



Here's the MHI flow map with efficiency islands.

Can we get this info for the N55 turbo???

[zltm089]

Great thread!!!!!!.......didn't undertstand all of it.... but some very useful info....

At least now I know that a stock 335i has about 8psi and the the only mod i have is a JB plus which will give me an extra 4psi .....and total comes to 12psi....and by what you guys wrote...I'm in the "safe" zone.... :-)


as a general guide, should we say that anything above 16psi is "a bit risky"....?

[zltm089]

Originally Posted by GTR-Dad

I'd love to see a sticky where members list their mods, tune, driving style (drag, circuit, spirited street driving etc) mileage at particular tune levels, and any problems they've experienced.

Dan

plus one...

[M3 Eater]

Id love to know the efficiency range of the turbo... lets throw safe out the window. If we wanted safe we would be driving mini vans!

Id like to know how much psi it takes before the turbo is making so much heat that the WHP is heading south and at what rep ranges. We could do two calculations, one for people with stock fmic and one for people with aftermarket fmic. For argument sake, say the stock set up was about 3-5 psi lower in the manifold than the target set and that after fmic drop 1-3 psi and show me something like this.
RPM stock aftermarket fmic psi efficiency cut off
1500 - 12- 14
2000 13- 15
2500 13 - 15
3000 13 -15
3500 13.5 - 15. 5
4000 14- 16
ETC..........

you know something us dumb guys that like to drive fast can understand.

It would be nice if we could plug our mods into a tuning program spread sheet.
Include mods like Down Pipes, intakes, exhaust, fmic. Just plug in what you have and have it tell you where to set your max targets for max whp and even take it further and estimate how long you can expect your induction system to last at each setting.

Id hate to think that I am pushing my car past the max range hoping for whp, getting less than i would a lower range, and wearing out my car faster as well while going slower. I personally am not interested in posting a bunch of high psi logs bragging how my car can sustain 19 psi from 1500-6300 rpms when some turbo genius knows and can share with us that x is the highest psi at y rpms given mods in said list.

I know thats what I was hoping to learn in this thread and I see the data is there! Even some crunching has been done. Then a bunch of effort spent bickering over pressure drop across a fmic that readers may or may not have. If someone could crunch a dummy cart with estimates than any numbers readers don't agree on they can adjust ie. the pressure drop across the fmic & all the pipes.

[ruphianh]

nice map

[jokergerm]

these turbos really spin at 200,000 RPM???!!!

[Aerotest]

Great!

[MPLICIT]

This is so useful thanks!