[WrxToBeamerGuy]

Originally Posted by virus_art

Hi! Could you guys please check this 4th gear pull log?
Is the timing correction acceptable or...?
I want to know if the numbers are fine or should i go with stage 2 91octane?

Stage 2+ 93octane map
https://www.bootmod3.net/log?id=6607...efb514fd3c14f1

2018 240i xdrive automatic
Catless dp and bosch tu hpfp.

Timing corrections are acceptable nothing to worry about. Check back when it gets warmer out because with warmer temperature they could become bad.

[virus_art]

Thanks for the review! Today I went for another log read and noticed that there were more corrections and one knock.
Outside temp was around 20'C.
Mind taking a look? I am having a dyno wisit this week to see what numbers the car is making and would like to be safe.
https://bootmod3.net/log?id=660ac1661aaf1446a0d46bae
Much appreciated. This community rocks.

[DieselDuck]

Originally Posted by virus_art

Thanks for the review! Today I went for another log read and noticed that there were more corrections and one knock.
Outside temp was around 20'C.
Mind taking a look? I am having a dyno wisit this week to see what numbers the car is making and would like to be safe.
https://bootmod3.net/log?id=660ac1661aaf1446a0d46bae
Much appreciated. This community rocks.

Yeah either try 95ron map, better fuel like 100/102ron or put some E85 in there if you really wanna be 100% safe in all conditions.

[virus_art]

Originally Posted by WrxToBeamerGuy

Timing corrections are acceptable nothing to worry about. Check back when it gets warmer out because with warmer temperature they could become bad.

Thanks, what are the things that could become bad once outside temps increase? At what point the timing corrections become unacceptable? once they are not able to recover in time? Sorry if this is an obvious question that has been answered here 100 times, I am still going through the whole post history.

[JonasM40i]

A question that i ask me is, on which value i can see, that for instance my downpipe is my bottleneck?

Perhaps I know from experience, that a 300 cell downpipe is usable for like 500 horsepower. But on which values can I see that?

[Skyhigh]

You cannot see that in a log. Hypothetically you could track calculated exhaust temperature etc. and derive from there, but you have no datum to compare to and there are multiple variables which will influence it.

In general - the downpipe is and will always be your exhaust bottleneck. Simple as that.
And please do not refer to cells - cells are like megapixels - marketing term only. You may have higher flow-resistance from a specific 200 cell than from a 300 cell. It all comes down to the specific product and its condition.

[Skyhigh]

Originally Posted by virus_art

Thanks, what are the things that could become bad once outside temps increase? At what point the timing corrections become unacceptable? once they are not able to recover in time? Sorry if this is an obvious question that has been answered here 100 times, I am still going through the whole post history.

Higher ambient temperature --> Higher intake temperature --> negatively influenced combustion (lower density oxygen).
You will naturally start seeing heavier timing corrections. There is no black or white point which can be defined in a sentence. One needs to look at the big picture of things.

[JonasM40i]

Originally Posted by Skyhigh

You cannot see that in a log. Hypothetically you could track calculated exhaust temperature etc. and derive from there, but you have no datum to compare to and there are multiple variables which will influence it.

In general - the downpipe is and will always be your exhaust bottleneck. Simple as that.
And please do not refer to cells - cells are like megapixels - marketing term only. You may have higher flow-resistance from a specific 200 cell than from a 300 cell. It all comes down to the specific product and its condition.

I am not only referring to cells, I only have stated what I am running at the moment.
I know that you have to consider the diameter, the shape/ flow and these stuff.
I am getting a 200 cell version which will be capable to 650/700 horsepower and I was curious if I could see differences in the lig with same software version.

[Skyhigh]

No, you cannot. There are too many variables and no direct sensor or value that measures exhaust back-pressure / resistance.

What you may be able to see however is a quicker spool of the turbo (hence quicker building up of boost once you hit the throttle at specific RPMs and gear), on the same map. I personally doubt it will be measurable between your 300 cell and 200 cell DP (the difference, if any, would be quite small), but that's the only thing in the logs (that I can think of) which could indicate a higher-flow exhaust system and relief on the turbo.

Don't expect miracles though.... keep this chart in mind, it is rather indicative about the difference between catted, high-flow DPs ...:

[JonasM40i]

Thank you for your input.

It is funny that you refer to a graph where different amount of cells are compared and above you wrote, that comparing cells "are marketing term only".

I am getting now a single 200 cell downpipe with 146mm diameter and optimised flow. In comparison the HJS 300 cell downpipe is much more restrictive. You can literally see the difference when you compare it side by side.

With my actual HJS downpipe my 550hp are max, whith the new one, 650 should be no problem. But lets see how it will work out.

[Skyhigh]

Not “funny” at all - the graph compares very specific 200 and 300 cell downpipes and is as such not generic, although indicative about the potential differences in performance.
Not sure what could be misinterpreted really…

Good luck with the new DP I think we went quite offtopic here.

[ycilgin]

Hello,
I flashed MHD Stage 1 95 RON map to my m240i then I logged it afterwards. I have a question, it might sound stupid but I am new here. Torque act. clutch nm reaches 480 at maximum which is lower than the claimed stock value. And according to my calculation using torque and rpm, the car making a 350 hp which is just 10 hp more than the stock. Is the torque value on MHD accurate? Or is there something wrong with my car? Car is running on 95 RON fuel and the spark plugs are 10k km old. I am leaving the datalog below for those who might want to review. Thanks!

https://datazap.me/u/ycilgin/2024-04...=15-26&mark=67

[JonasM40i]

In my opionion, the timing corrections aren´t looking good at all. They are not dangerous high, but also not good. Perhaps your fuel isn´t that good. I think you know that, because you flashed the "smallest" map.

Would be interesting to see a log with stock map.

[Skyhigh]

Originally Posted by ycilgin

Hello,
I flashed MHD Stage 1 95 RON map to my m240i then I logged it afterwards. I have a question, it might sound stupid but I am new here. Torque act. clutch nm reaches 480 at maximum which is lower than the claimed stock value. And according to my calculation using torque and rpm, the car making a 350 hp which is just 10 hp more than the stock. Is the torque value on MHD accurate? Or is there something wrong with my car? Car is running on 95 RON fuel and the spark plugs are 10k km old. I am leaving the datalog below for those who might want to review. Thanks!

https://datazap.me/u/ycilgin/2024-04...=15-26&mark=67

Timing corrections don't look good. To analyse the full picture, you need to select Timing delta for knock in your logs (use the default set of parameters). It does look like your fuel is crap though.

[ycilgin]

Originally Posted by Skyhigh

Timing corrections don't look good. To analyse the full picture, you need to select Timing delta for knock in your logs (use the default set of parameters). It does look like your fuel is crap though.

Thanks for your reply. I will log the car with default parameters. By the way, the car is running on the best fuel I can find here. If the problem is caused by fuel, should I go back to stock? Would it be dangerous to drive as it is right now?

[Skyhigh]

Originally Posted by ycilgin

Thanks for your reply. I will log the car with default parameters. By the way, the car is running on the best fuel I can find here. If the problem is caused by fuel, should I go back to stock? Would it be dangerous to drive as it is right now?

Need to see full log with all important parameters to answer that.

Bear in mind that fuel quality can vary between different gas stations from the same chain or even within batches, at the same station. I have experienced that here too.

[ycilgin]

Originally Posted by Skyhigh

Need to see full log with all important parameters to answer that.

Bear in mind that fuel quality can vary between different gas stations from the same chain or even within batches, at the same station. I have experienced that here too.

Here it is:
https://datazap.me/u/ycilgin/mhd-sta...og=0&data=3-17

[Skyhigh]

This indeed looks quite bad! Do not drive this setup!! It is dangerous and you are not making any power, clearly (you see you are doing 460 Nm torque only).
As far as I can see however this is now Stage 1 RON 98 map!? The previous one was on Stage 1 RON 95. Are you now running a 98 map with 95 fuel, if that's the best available around you!???

[WrxToBeamerGuy]

Originally Posted by virus_art

Thanks, what are the things that could become bad once outside temps increase? At what point the timing corrections become unacceptable? once they are not able to recover in time? Sorry if this is an obvious question that has been answered here 100 times, I am still going through the whole post history.

The basic concept is that the car pulls timing to reduce the chance of the engine knocking. The fact that the car pulls timing is actually a good thing that way there is no knock (pre detonation). You can use the pulled timing as an indicator that the car would be knocking if the car wasn't programmed to reduce timing by itself. So that being said, timing being pulled on one or two cylinders is usually not a big deal and can be ignored. Timing being pulled on all cylinders across the board whether its -2 or -5 indicates the octane is too low for the tune. This is because octane is not an indicator of how much energy is in the fuel but is actually an indicator of how knock resistant the fuel is. So put in higher octane fuel (more knock resistant fuel) and you will get less timing corrections.

Finally, the thing we don't want to see is actual knock events (timing being pulled is preventing those from happening). A single knock event here or there isn't a big deal because maybe you got a bad batch of low octane fuel. But to have multiple knock events in a single pull or a knock event that never goes away can lead to damage. The DME can only pull -10 degrees of timing at full load on the stock tune and unless your tuner changes that (which no tuner increases to -15 they will most likely decrease it... but that's a different story) once you go above -10 degrees of timing pull you will seriously knock consistently and probably end up seriously damaging the engine.

[ycilgin]

Originally Posted by Skyhigh

This indeed looks quite bad! Do not drive this setup!! It is dangerous and you are not making any power, clearly (you see you are doing 460 Nm torque only).
As far as I can see however this is now Stage 1 RON 98 map!? The previous one was on Stage 1 RON 95. Are you now running a 98 map with 95 fuel, if that's the best available around you!???

Ahhahahaa I guess I accidentally flashed 98 map. I feel embarrassed.

[Skyhigh]

You should be more careful. That’s how you accidentally kill an engine.

[ycilgin]

Hello,
I flashed MHD Stage 0 map, afterwards I flashed Stage 1 95RON map. As I was comparing the datalogs, I noticed that stage 1 map has lower maximum torque and makes almost the same maximum power. Is it possible that the torque at clutch value is not accurate? Or is there something wrong with my car? Datalogs are below for those who might want to review. Thanks in advance!

Stage 0:
https://datazap.me/u/ycilgin/stage0?log=0&data=20-33-52

Stage 1:
https://datazap.me/u/ycilgin/stage1?log=0&data=20-33-52