243 replies to this topic

[Exmantaa]

Looking good.

Do some more fuel learning, as the new injectors do not have to work so hard, and that needs to be learned. As for the 6600 to 7k, there are a lot of obdtuner people suffering from that. One of the biggest mysteries out there.  

 

Well, if there is one graph showing an "OBD limited power" it is this one; due to you larger pulley the M62 charger keeps the same torque level well in the higher rpms, untill "something" at 6.6K  drops torque and power off the cliff. And I see no mechanical reason that could cause that behavior...

 

Your power is so linear that I would set the rpm limit to 7K and see if the measured drop off also rises by 200rpm. (7K is a safe limit on stock cams and valve springs.)

And then, after the fuel learns, start playing with some ignition timing.

Edited by Exmantaa, 05 September 2016 - 11:16 PM.

[CHILL Gone DUTCH]

Frank I believe the drop ffs are due to oem protection The OEM ECU software has a number of protection systems build in which protect the engine. For instance with long full throttle power is asked, the ignition will be retarded after a certain amount of time which reduces power and increases exhaust temperatures. So you have more chance of activating the protection of runs are done in third gear

[CHILL Gone DUTCH]

So if you start the power run higher up the Rev range there is less chance of triggering it

[smiley]

So if you start the power run higher up the Rev range there is less chance of triggering it

 

Can you be a bit more specific, as my clutch does not like launching from 5k rpm.

[CHILL Gone DUTCH]

I mean have the clutch engaged and carry out the power run around 4K rpm instead of 1500-2000 rpm

[Captain Vimes]

I still believe the strange power graphs are related to a measurement issue rather than a genuine drop in power. The ecu is recording during WOT. When the limiter is reached, acceleration slows and Rpm's drop while foot is still flat on the floor. This data overwrites what was stored and appears as a power drop.

[smiley]

I still believe the strange power graphs are related to a measurement issue rather than a genuine drop in power.  

 

That is how my bumb dyno feels it also.  

[CHILL Gone DUTCH]

Try and start the power run higher up the Rev range and see if you still get the drop

[smiley]

Still all the way into the revlimiter, or with the trick to slightly back off near the target?

3rd gear?

 

[CHILL Gone DUTCH]

Try it both ways smiley Start power run at 3500 rpm and try and predict the limiter And then start at 3500 rpm and hit the limiter

[Jocke_D]

 

Looking good.

Do some more fuel learning, as the new injectors do not have to work so hard, and that needs to be learned. As for the 6600 to 7k, there are a lot of obdtuner people suffering from that. One of the biggest mysteries out there.  

 

Well, if there is one graph showing an "OBD limited power" it is this one; due to you larger pulley the M62 charger keeps the same torque level well in the higher rpms, untill "something" at 6.6K  drops torque and power off the cliff. And I see no mechanical reason that could cause that behavior...

 

Your power is so linear that I would set the rpm limit to 7K and see if the measured drop off also rises by 200rpm. (7K is a safe limit on stock cams and valve springs.)

And then, after the fuel learns, start playing with some ignition timing.

 

 

Got the exact same behaviour when the limiter was set at 6400. Some pulls did get a different "look" and seemed to keep on a bit further. Don't think my behaviour when hitting the limiter was any different but can't be sure of course...

 

Will try 7000 and do some fuel learning. Hopefully tonight or tomorrow. TD at Kinnekulle Ring is closing in fast...

[Exmantaa]

Frank I believe the drop ffs are due to oem protection The OEM ECU software has a number of protection systems build in which protect the engine. For instance with long full throttle power is asked, the ignition will be retarded after a certain amount of time which reduces power and increases exhaust temperatures. So you have more chance of activating the protection of runs are done in third gear

 

 

Still unsure if what we see on the graphs is an OBD measurement glitch, or indeed a protection system kicking in...

But for the latter I still do not understand why the power is then dropping like that, as the OBD logged MAP pressure, the fuel AFR (has not that much influence on power) and the timing advance numbers all give no reason for a power drop like that...

Or it must be that the logged parameters are not the real engine parameters and f.i. the ignition gets more retarded  there than the OBD log shows.

Only way to be sure what is happening is on a dyno and measure the real ignition advance on full load...

   

[Captain Vimes]

Here's the difference I get in measurement from lifting right at the limiter (took a number of attempts) vs hitting the limiter. Then about 5 mins apart with no changes to any parameters..

[Captain Vimes]

Dyno would be the best way to confirm.

[Jocke_D]

Here's the difference I get in measurement from lifting right at the limiter (took a number of attempts) vs hitting the limiter. Then about 5 mins apart with no changes to any parameters..

 

And I guess the red one is when you lifted ?!

That was the feeling I got at least.

[Captain Vimes]

Yes, red line is with lifting - flat torque all the way to the limiter. Your graph looks good to me. Not sure I can help with the sporadic performance. It's not normal. Chill is the expert... Have you done a thorough fuel learn and logging session?

[CHILL Gone DUTCH]

is it me or does captains and my power run where we guessed the limiter rather than hit it has a similar pattern 

[Exmantaa]

I see what you mean, the slight "drop zone' just before max power. But yours is more exaggerated, as usual....

[ufods]

....mayby it is something like a "soft" limiter before the limit kicks in?

[Jocke_D]

I guess I can live with the strange cut off phenomenon for a while. I still have lots to learn before that starts to bother me

 

Yesterday I tried to do a fuel learn, for the first time. Read the manual but was a bit confused so I think I made some unnecessary stuff.

 

Would this be the correct strategy/behaviour:

Start and warm up the car + Connect tablet (in my case) with OBD, start OBDTuner

Enter learn mode and drive around for a while, mixing hard pulls with some steady revs throughout the rev range

"Read from ECU" (this should give lots of numbers in the cells under "measurement"?!)

Continue to drive around trying to hit the cells not gone green

"Read from ECU" again to see what has happened?

Rinse and repeat...

When satisfied - "Process measurement" and see what happens under the Fuel tab ?!

If it looks ok - make calibration permanent???

All done ?

 

I think I did not get that "Process measurement" was to be done when learning is complete (did that every time after "Read from ECU") so I created lots of crap files.

 

What is your driving strategy during learning?