[zackz]

Originally Posted by DWR

We must be talking RWHP, because some have already achieved this at the crank. It depends on the driveline loss, because max airflow indicates it is a close call. Efforts to move more air in the upper rpm's is the key. Just 5% more air would get you there.

Maybe I should say 5% more oxygen, food for thought.

Yeap 400 hp at the crank can be easily achieved with only the downpipe and remap, but boost goes crazy...

If your tuner don't know the trick to control the boost at that power level, you will face limp modes, or huge boost levels if your tuner has removed the stock DDE boost protections...

And without working on the wastegate, you will have huge back pressure before the LP turbo turbine, so less HP's too...

[DWR]

Originally Posted by zackz

Yeap 400 hp at the crank can be easily achieved with only the downpipe and remap, but boost goes crazy...

If your tuner don't know the trick to control the boost at that power level, you will face limp modes, or huge boost levels if your tuner has removed the stock DDE boost protections...

And without working on the wastegate, you will have huge back pressure before the LP turbo turbine, so less HP's too...

Do you have data to support these statements? I don't know anyone who has done at the crank testing with everything attached. Can you give us the driveline losses?

[zackz]

Originally Posted by DWR

Do you have data to support these statements? I don't know anyone who has done at the crank testing with everything attached. Can you give us the driveline losses?

Will do as soon as possible

[fsd350]

Originally Posted by TDIwyse

Excellent thread topic.

iaknown encouraged me to do more investigating on what my boost numbers were actually doing (thanks again). Turns out the Bav Tech data reported by the DDE was not "actual" boost numbers (although the Android Torque #'s were pretty close through most of the rpm range). So... some background from the 335d SCR Catalytic Converter thread

http://www.e90post.com/forums/showpo...4&postcount=92

Further testing today revealed some discrepancy to my previous description of 4th gear. And I took some video of gauge vs rpm in 3rd and 4th to better evaluate the readings. 4th gear at full fueling was actually peaking at ~37 psi at the 2800 rpm area and would then come down to ~34-35 psi and stayed there up to defueling at ~3900 rpm where I let off the skinny pedal. 3rd gear was pretty much as described previously.

The 4th gear data was concerning as it's off the compressor map ... so I decided to slip the DEF "mixer" back in place (#3 here http://www.realoem.com/bmw/showparts...15&hg=18&fg=10) and see what the extra restriction would do.

Well, it actually made a significant difference. Haven't video recorded this condition yet, but visually (and comparing the Torque data logs for 4th gear pulls) peak boost at the 2800 rpm point is down ~2-3 psi and sustained boost above 3000 rpm was down ~3-4 psi. So the Autometer gauge is now reading ~30-31 psi range from about 3000up to ~4000 rpm and then below 30 psi from 4000-4200 rpm. This is better as it puts things back on the compressor map.

Would be interested in comparisons from others with open exhausts to see if they see similar results with sticking the mixer back in place (which is pretty easy actually ... just need to unbolt the downpipe from the midpipe and there was enough flex in the downpipe section to move it enough to slip the mixer back in place).

Video of boost behavior with the open exhaust for a 3rd and 4th gear pulls can be seen here:


3rd

4th

So ... I'm trying an alternate approach to iaknowns mod, which involves an external wastegate. It's weighing in about the same as the EGR cooler. Finished getting it installed late yesterday (it's tight in there and took a lot of custom shaping/welding) but haven't had time to play with setting the response yet. Won't get to that until next week due to other responsibilities and time commitments. Will report back on findings.

TDI,

In what way is the BT tool not measuring boost properly? Just curious as I have been using the BT tool for logging and I will finally be installing my Autometer gauge this weekend. My top boost according to BT is 28.5 psi subtracting atmospheric pressure. This at around 3000 rpms ful fueling, Jarek Stage 2,All deletes except SCR cat and stock exhaust in place for now. Oh yeah, almost forgot 9/16 ported gate too. Thanks

[TDIwyse]

Originally Posted by fsd350

TDI,

In what way is the BT tool not measuring boost properly? Just curious as I have been using the BT tool for logging and I will finally be installing my Autometer gauge this weekend. My top boost according to BT is 28.5 psi subtracting atmospheric pressure. This at around 3000 rpms ful fueling, Jarek Stage 2,All deletes except SCR cat and stock exhaust in place for now. Oh yeah, almost forgot 9/16 ported gate too. Thanks

The Bav Tech tool appears to be reporting the "desired" boost and not the actual boost. The actual boost (as measured by the analog gauge and TestO) was much higher than the Bav Tech reported. TestO can see both the desired and actual (STAT_LADEDRUCK_WERT).

DWR figured out several import PID's for the Torque app that are extremely helpful. But with that intake boost value I get I need to multiply by 1.11 to get agreement with TestO and the analog gauge.

Without DWR's PID's for Torque, you need to rely on an approximated equation that uses the MAF value, engine displacement, and a fixed Volumetric Efficiency term. The VE term, however, is not constant (for example across the rpm range there's significant variation) so that back calculated boost method is also off. And, if you have the stock EGR system operating, during many conditions much of the intake air is bypassing the MAF (it's coming from the EGR path) so the calculated boost will read low.

At least these have been my experiences with my car.

[fsd350]

Thanks TDI. It will be interesting to see what my true boost pressure is.

[BB_cuda]

FS, you have a little bit of a mixed bag right now. My car was in your config for only 50 miles. Ported internal WG but still on "more closed" OEM exhaust. So, you should have lower boost for both these reasons. I have NPT plug in the cut face of the EGR valve after cutting EGR motor drive off. I believe TDI was running analogue gage from there too. Where are you measuring analogue boost from?

[fsd350]

Originally Posted by BB_cuda

FS, you have a little bit of a mixed bag right now. My car was in your config for only 50 miles. Ported internal WG but still on "more closed" OEM exhaust. So, you should have lower boost for both these reasons. I have NPT plug in the cut face of the EGR valve after cutting EGR motor drive off. I believe TDI was running analogue gage from there too. Where are you measuring analogue boost from?

Most likely the upper side of the charge pipe before the TB for now. Going to get on it a little later this morning.

[DWR]

Originally Posted by TDIwyse

DWR figured out several import PID's for the Torque app that are extremely helpful. But with that intake boost value I get I need to multiply by 1.11 to get agreement with TestO and the analog gauge.

Anyone else have a discrepancy between the custom Torque PIDs and actual readings? I would be happy to modify. My analog gauge was not tapped near the OEM pressure sensor, so I was not sure if that had an effect.

[fsd350]

[QUOTE=DWR;18423039]Anyone else have a discrepancy between the custom Torque PIDs and actual readings? I would be happy to modify. My analog gauge was not tapped near the OEM pressure sensor, so I was not sure if that had an effect.[/QUOTE


DWR, my readings seemed be lower than the default when I tried them. I may have loaded them incorrectly. I did not spend too much time with it. May have something to do with my old Samsung junk phone I used it on too. Always locking up which frustrates the living s**t out of me. So my readings were probably irrelevant. I have an iphone so it is just for a backup. Interestingly enough, Dashcommand for iphone showed totally different readings as well. Once I get some good analog readings, I will post my findings from Torque, BT, Dashcommand and true analog boost. REALLY enjoy learning and sharing experiences with you guys.

[Thecastle]

Originally Posted by DWR

Anyone else have a discrepancy between the custom Torque PIDs and actual readings? I would be happy to modify. My analog gauge was not tapped near the OEM pressure sensor, so I was not sure if that had an effect.

I'm just going to mention this.... How do we know anyone's analog gauge measurements are accurate. Analog boost gauges are notoriously inaccurate and I've not seen anyone stating theirs was calibrated.

Also boost levels vary on most cars with temperature and altitude. So again I've not seen any of those factors taken into account. So I'm not sure torque is inaccurate, or that folks measurements are highly accurate either.

[TDIwyse]

Originally Posted by Thecastle

I'm just going to mention this.... How do we know anyone's analog gauge measurements are accurate. Analog boost gauges are notoriously inaccurate and I've not seen anyone stating theirs was calibrated.

Also boost levels vary on most cars with temperature and altitude. So again I've not seen any of those factors taken into account. So I'm not sure torque is inaccurate, or that folks measurements are highly accurate either.

Valid point. That's why I've done direct comparisons. For example, I've done video recorded comparisons of the analog gauge while measuring with either Torque/Bav Tech/TestO for comparison for the same pull. TestO and the analog gauge are the most directly comparable results and are accurate to within the scale of the analog gauge. Now, it's possible that both of those two methods are off by precisely the same amount, but I'm using them as the "standard" for my measurement reference due to how they have verified each other.

[fsd350]

I've decided to tap mine in the manifold. I'll tee off of that same location for signal when I install meth system down the road. After thinking about it a bit, it doesn't seem as accurate to monitor in front the throttle plate or EGR even though it is blocked and the throttle plate is more of an overrun safety device and idle smoother. Good point on calibration. I'm at 6,800 feet in altitude which puts me at about 11.5 psi atmospheric pressure.

[rspring]

I had mine bored out to 9/16 while disassembled and the turbos rebalanced, put in new bearings and resealed. With Jarek's stage two, Banned One DP, Wagner IC and Snow 2stage w/m, ABC (-) it is much smoother on power delivery. Obviously much more power as well, but I'm really impressed with the drivability. SCR delete next, as soon as exhaust is available from a certain banned person. The turbo builder was aware of the boost spike issue with backpressure reduction. Right now I'm getting very smooth boost numbers, but I'm not able to beat on it much yet, so I have not seen anything north of 30lbs. My second stage w/m kicks in at 27psi now, and that works nicely, but I run out of road too quickly to hold it long.

[DWR]

Originally Posted by TDIwyse

Valid point. That's why I've done direct comparisons. For example, I've done video recorded comparisons of the analog gauge while measuring with either Torque/Bav Tech/TestO for comparison for the same pull. TestO and the analog gauge are the most directly comparable results and are accurate to within the scale of the analog gauge. Now, it's possible that both of those two methods are off by precisely the same amount, but I'm using them as the "standard" for my measurement reference due to how they have verified each other.

As you compare more methods, the probability of agreement between any 2 increases. Best method I know is to use the vapor pressure of butane. You can measure and control its temperature and get a pretty accurate standard pressure. Just a fun experiment for the nerds

[Deftronix]

TDI - Nice work on the EWG and thanks for sharing all your effort! Realize this is an old thread but wanted to dig it up.

Read through and noticed that you used 1" piping. Browsing turbosmart offerings there seems to be an increase in inlet diameter on the flange from 1 1/2" to 1 5/8" pipe OD between their Ultra-Gate38 regular and HP (high pressure, upto 40psi? ) series leading me to think there was a reason they increased the inlet OD? Considering the boost levels you are running, do you think it would benefit from an increased diameter in piping?

Seems to have resolved your overboost issues so don't see why it would, but thought it was odd running 1" OD piping just fine at almost the max boost levels they are calling for 1 5/8".

[TDIwyse]

Originally Posted by Deftronix

TDI - Nice work on the EWG and thanks for sharing all your effort! Realize this is an old thread but wanted to dig it up.

Read through and noticed that you used 1" piping. Browsing turbosmart offerings there seems to be an increase in inlet diameter on the flange from 1 1/2" to 1 5/8" pipe OD between their Ultra-Gate38 regular and HP (high pressure, upto 40psi? ) series leading me to think there was a reason they increased the inlet OD? Considering the boost levels you are running, do you think it would benefit from an increased diameter in piping?

Seems to have resolved your overboost issues so don't see why it would, but thought it was odd running 1" OD piping just fine at almost the max boost levels they are calling for 1 5/8".

You're welcome.

The 1 inch OD pipe I'm using is mainly due to how the EGR port is setup, and it also makes routing the piping easier. And at the relatively small displacement of our engines, even at higher boost levels, the 1 inch pipe has been more than sufficient to control boost. The matchbot simulator tool also shows this size being more than sufficient and having margin to handle more.

In a larger displacement engine at those boost levels going to larger diameter piping would become important.

[drhousedk]

Hi,

I'm currently having overboost issues on a 335d with DPF removed and remap. Overboosts with stock map aswell, so seems to be DPF removal related.

Which exact blocks should I log in TestO to produce the ratio maps you're doing? Inlet pressure seems obvious, but what about exhaust pressure?

Troels

[TDIwyse]

Originally Posted by drhousedk

Hi,

I'm currently having overboost issues on a 335d with DPF removed and remap. Overboosts with stock map aswell, so seems to be DPF removal related.

Which exact blocks should I log in TestO to produce the ratio maps you're doing? Inlet pressure seems obvious, but what about exhaust pressure?

Troels

Not sure which version of the DDE you have, but on my North American car the following parameters might be helpful:

STAT_Exh_pTrbnUs_full_WERT -> Exhaust Manifold Pressure
STAT_LADEDRUCK_SOLL_WERT -> Boost Desired
STAT_LADEDRUCK_WERT -> Boost Actual

Looking at what the engine is doing with STAT_LADEDRUCK_WERT vs STAT_LADEDRUCK_SOLL_WERT might give some insight as to why you are getting an overboost condition. For example, your actual boost might be significantly higher than the value the DDE wants to see... If that is the problem, then fixing it can become more involved. If the wastegate is operating correctly, you might need to modify the size of the wastegate hole (a fair bit of fussing around), or remap the DDE to try and correct the issue somehow, or add restriction into the exhaust to try and reduce flow (like putting the DPF back on)...

[Yozh]

Originally Posted by TDIwyse

...or add restriction into the exhaust to try and reduce flow (like putting the DPF back on)...

Too bad that euro downpipe connection is not the same. SCR mixer I thought was a good option to easily add back some backpressure.

[drhousedk]

Originally Posted by Yozh

Too bad that euro downpipe connection is not the same. SCR mixer I thought was a good option to easily add back some backpressure.

Yeah, I was thinking the same thing. I really envy you guys for having the option of the mixer.

[Mrdeezy]

Originally Posted by Yozh

Are we talking about boost? My simple calculator says that 3300mbar is 48psi. And this is a safe max? I was under impression that if you are over 30psi (2100mbar) boost then that needs to be tackled. Can we please clarify?

I never saw this question answered. Can someone with some knowledge of this chime in?