[milesr3]

Folks,

I received the DashDyno SPD (http://www.auterraweb.com/dashdynoseries.html) I ordered and unsurprisingly the first thing I did was run off some dyno plots of my standard (unmapped) 2005 535d:

(now deleted)

I've also run off some logs of boost pressure vs. rpm and it's maxed out (capped) at 22.3psi (gauge), which seems a bit low? I thought the 535d has ~2.85bar / 26.6psi on tap...unless the boost figure via the OBD isn't reliable?

[edit] I've deleted the dyno plot as it is wrong. I now realise that I had the gear ratio wrong for 3rd, which has exaggerated the figures and that they are 'at the wheels' figures. Doing some quick calculations seems to show I was getting ~290bhp and 410lbft, but I'm going to do some more runs later.

[F104]

Welcome to the real (diesel) world. My dashdyno is also a few bhp down on bhp. You would expect that, as published curves are flywheel bhp with no drive-line or accessory losses.
However torque is another story. Published torque curves are done on a dynometer of some form, and the engine is pulled down from max bhp to lower rpms. The equivalent of driving full throtthle uphill while pulling one large trailer, and loosing rpm. The turbo is blowing at full speed at all times here.
On acceleration like plotted with the dashdyno the turbo speed is lagging while engine rpm is increasing. So you'll see a peak torque at higher rpm then on a published curve, and well down too as the turbo is still catching up. Sometimes called the no-air torque curve.
This is one reason why diesel automatics can be faster on drag racing. Here you can floor the throtthle while keeping the brake depressed, which 'loads' the engine vs the torque convertor (and increases transmission oil temp very fast). But the load on the engine gets the turbo on speed. dbx335 is likely the expert here.
I should have my Evolve switch tomorrow, i'll try to get before and after curves by the end of the week.
PS 335d is off course automatic. To get reliable figures you need to do these in one gear, the one you set up in the dynometer setup file. If transmission changes gear in the pull results will be off. I do these (MT) in 4th from 1000rpm, which implies accellerating thru 100mph to get over the 4000-4500 peak in the bhp curve. 3rd gear goes too fast, 5th gear would be nice (slower pull and turbo can catch up). But 5th means very slow acceleration from low rpms, and the ability to keep going thru 120mph in traffic..

[F104]

and yes my boost readout is limited too to 155kpa, or about 22.3psi. I think this is just a limit in the broadcasted value, as on every hard accel it goes to 155 and stays there.

[dxb335d]

when did you buy a 535d mate? any pics buddy!?

I thought x35d boost stock was more like 40psi

[F104]

can't find this in english - but not too difficult to read. 335d should be almost 43 psi (2.95 in the M57 column)

cheers,

[dxb335d]

For some reason when I posted f104 was the first post hence asking if you had changed car.

[milesr3]

Originally Posted by F104

and yes my boost readout is limited too to 155kpa, or about 22.3psi. I think this is just a limit in the broadcasted value, as on every hard accel it goes to 155 and stays there.

Thanks, well that's good to know after all the turbo actuator problems I had. I think I read somewhere else that the boost figure via OBD can't be relied upon as well.

I didn't get time to do some more runs yesterday, but will nip out at lunchtime. I hastily deleted a bunch of runs which were around 230bhp and 350lbft of torque thinking I'd still got the gear ratio wrong (despite measuring it a million times), but I hadn't realised that these were at the wheels figures. Adding 18% for transmission loss gives ~270bhp and 413lbft, which is where it should be with the pre-LCI 535d.

With the auto box, I'm doing the runs in 3rd which is nudging 100mph to get over the 4500rpm power peak. I'm trying to start as slow as possible so that the torque converter is locked, which seems to be around 40km/h. Then (as you say) it takes a short while for the boost to build.

Did you say that you'd had a CIP update, which had enabled you to see exhaust gas temperature, or was this a DashDyno update? My DashDyno is running 3.0.6 and I can't see the exhaust gas temperature, nor intercooler temp which is a shame. Also mine does not read any values with fast sampling and CAN6x enabled.

Will be interesting to see your before/after figures for the evolve remap.

[F104]

Mine is still a 3.0.5, the .6 is not yet on their site. I had boost temp from day 1, it shows up as "intake air temperature". Yes I'm sure that in the beginning i had no exhaust gas temperature, and it only showed up after the car came back from the dealer with updated software. This one shows up as "catalyst temp B1-S1". I too had issues with fast sampling and Can6x. I believe the auto 0-60mph timer would not reset at each stop.
Ps did you set the power down to rpm? if not you'll ECU will stay on for 30 minutes

Got the evolve box first thing this morning & and should have the new map later today

[doughboy]

Originally Posted by F104

can't find this in english - but not too difficult to read. 335d should be almost 43 psi (2.95 in the M57 column)

cheers,

Note that figure is absolute pressure, not 'gauge' or relative to atmosphere pressure. So even at rest (engine off) you would have 1 bar(abs) of boost.

So 2.95 bar (abs) would be near enough 1.95 on a pressure gauge.

Tell me, does the dashdyno read zero or 1 bar boost when the engine is off?

If it reads zero then it isn't reading bar (abs).....

This may explain the differences.

[M5 TT]

Beat me to it

Still 2 bar standard is getting to be crazy pressures

[milesr3]

OK Folks, have done a few runs with the correct gear ratio as measured and verified in the DashDyno gear ratio wizard. Here are a couple of graphs:




All are rear-wheel horsepower and torque figures, corrected for the ambient conditions (temperature, barometric pressure, humidity and altitude).

The average power and torque figures are 241bhp and 334lbft at the wheels, which is around 284bhp and 394lbft at the crank assuming 18% gearbox loss.

[milesr3]

Originally Posted by doughboy

Tell me, does the dashdyno read zero or 1 bar boost when the engine is off?

Yes it does. There is a calibration value in there for ambient pressure, which you can measure when the engine is switched off.

[milesr3]

Originally Posted by F104

Mine is still a 3.0.5, the .6 is not yet on their site. I had boost temp from day 1, it shows up as "intake air temperature". Yes I'm sure that in the beginning i had no exhaust gas temperature, and it only showed up after the car came back from the dealer with updated software. This one shows up as "catalyst temp B1-S1". I too had issues with fast sampling and Can6x. I believe the auto 0-60mph timer would not reset at each stop.
Ps did you set the power down to rpm? if not you'll ECU will stay on for 30 minutes

Got the evolve box first thing this morning & and should have the new map later today

I have intake air temperature but no catalyst temperatures.

I may try fast samping again as it suggests that you need it for power/torque runs, but it seems to stop all parameters except speed and rpm...which thinking about it might still allow the power/torque runs to work and will give a few more samples than I'm getting now.

I have set it to power down with zero rpm - thanks!

[M5 TT]

can you log boost and put it on the same graph as power?

[milesr3]

No. The power/torque wizard is measuring acceleration and calculating power/torque given mass, drag, frontal area etc.

You can log boost against up to 15 other parameters though. Unfortunately it seems that the intake air temperature is before the turbos and cooler as mine is hovering around 30C.

[M5 TT]

Yeah, that is the only thing I can read with INPA

[milesr3]

Have done a couple more plots with fast sampling and CAN6x enabled, which seems to produce smoother curves (which would make sense if it was getting more data). It looks like it produces more consistent results as well with 240/241 bhp and 330/327lbft respectively.




So that's a fairly repeatable 283bhp and 390lbft assuming 18% transmission loss as a baseline before I get the remap done.

[F104]

So got my evolve map in. In one word: wow! As others have said day and night difference, also in the way the engine runs

Did some dyno runs but don't get the consistent results I wanted, but then there is no real flat motorway where i live. And pulling thru 4700 rpm (in 4th) is up to 110mph - not easy - people think I'm a moron going from 20mph on the entry lane to 110 in the 3rd lane.

Below the results of 3 good runs each: I know too the car only should have 130kW in the first place, but the important bit is the difference. Can't find errors in my set-up file, and my dealer also stated my car goes better than other E9x 320d's they see

original 1: 339Nm@2800, 143kW@4300
original 2: 328Nm@2600, 135kW@4300
original 3: 326Nm@3600, 138kW@4100

modified 1: 416Nm@3100, 167kW@4000
modified 2: 407Nm@3600, 162kW@4200
modified 3: 395Nm@2500, 160kW@4400

Might look as figures are all over the place but a look at the graphs shows it really depends at what rpm the max value is (original on the left, modified on the right, unfortunately the scale adapts so the increase doesn't stand out. However it looks and feels like torque is there earlier:

[milesr3]

I can relate to how hard it is to get consistent runs. I've probably done a dozen or more today to get a handful of usable graphs (remembering to switch the aircon off as well).

Luckily I have a flat, well sheltered stretch of dual carriageway nearby with a slow roundabout onto it and an exit that I can come off and loop back, which also compensates for any wind/incline changes. I know what you're saying about going from around 20 to 110mph though! Luckily my road is very quiet so I don't need to change lanes or anything.

Are you using fast sampling on those graphs? They look very peaky.

The slightly elevated original power values could be down to having the gear ratio wrong. I've measured mine via the gear ratio wizard many times as well and you do need to drive and check the calculated speed afterwards to verify it's right. I mistakenly assumed that the gear ratio wizard updated the dyno setup file as well, so left the gear ratio as 1:1 for the first run I did and got over 1000bhp, which would have been nice However it doesn't matter as long as you use the same ratio for comparison purposes.

Otherwise, some very nice gains from the evolve remap. I'm looking forward to getting mine done even more now.

[F104]

No - fast sampling was off.. And i switched back already once back to the original file as i didn't notice the count down timer - so started all runs to early and had to redo. I'm not going back again - the engine feels soooo much different.
Mine is a MT, i got the gear and diff ratio's from the brochure.

cheers,

[F104]

Originally Posted by milesr3

Unfortunately it seems that the intake air temperature is before the turbos and cooler as mine is hovering around 30C.

On the 320d the temp sensor sits halfway up the pipe from intercooler to engine. It reads -40C with the engine off, i get about +6C over ambient steady state, but on WOT accel it goes up to 60C over ambient..
Check http://bmwfans.info

[milesr3]

Originally Posted by F104

Mine is a MT, i got the gear and diff ratio's from the brochure

The gear ratios are known to automatic transmission as well and even with the torque converter locked up at a constant, high speed they are not accurate in my case (allowing fr tyre wear). According to the specs for the 6hp26, my overall 3rd gear ratio is 1.52 x 2.56 = 3.89, yet I've measure values in the range of 4.10 to 4.11 with 4.11 being most accurate when checking actual speed versus calculated.

Multiplying torque by 4.11/3.89 is a 6% over-estimate.

The difference in my case comes I believe from having worn rear tyres: 3mm of tread versus 8mm is 5mm less, which is 31.42mm less circumference off a nominal 657mm circumference tyre, which makes the gearing 5% lower and thus measured torque 5% higher.

You could accurately measure your tyre circumference (at speed to allow for ballooning), but the DashDyno gear calculator wizard is easier

Find a flat road and engage cruise control in your chosen gear for power/torque runs and see if the gear ratio wizard (under the dyno menu) agrees with your current ratio.