BRZ with header, overpipe and tune. OpenFlash / ECUTek before and after

[jamesm]

Originally Posted by Shiv@Openflash

Customer can't stay wide open in it because the engine falls flat and misfires. Neal@EQ can comment on that.

To the engine, all it sees is load (airflow/rev). It doesn't actually see about MAP. MAP is an load estimate. It's just an indication of the air pressure in the manifold. VVT (among other things) effect the correlation between MAP and actual engine load. So to me, engine load cuts (as opposed to MAP cuts) is the better approach.

As always, your mileage may vary.

i don't know what you mean by 'MAP is a load estimate'. Load is a load estimate. MAP is manifold pressure. I agree that MAP is only one factor contributing to engine load... hence why when trying to limit manifold pressure you'd want to use the MAP sensor, not load. Of course also just using the stock map means that there is no activation delay or way to control oscillation between the two states.

i can't see the advantage of an ignition/load-based strategy over one that actually cuts fuel based on manifold pressure. different strokes for different folks, i guess... certainly wouldn't be the first time we've disagreed on a technical issue like this, probably not the last .

[ProjectD]

Originally Posted by transition

That would be an interesting comparison. I'll ask the tuner first what the key differences are between tuning an EcuTeK vs OpenFlash vehicle. If we could squeeze something in i'd definitely like to see that result as well.

Originally Posted by Cockatoo

IN for OFT comparisons....

What ^^ they ^^ said....

Originally Posted by husker741

The thing that is nice about the OFT is that you can sell the tablet eventually and get some money back. With a custom Ecutek tune, you really can't do that other than sell the cables or something. So I would rather have a custom OFT tune than a custom Ecutek tune.

same here.

[transition]

Originally Posted by Shiv@Openflash

That's fine. I'm just pointing out that you chart compares the lower of 2 pulls on the OFT tune to the highest of 10 pulls on the Ecutek. By no means am I saying this was intentional. But I think it's important info to mention because a somewhat different picture is presented when comparing apples to apples. If you give me permission (this is your thread afterall) I can post up another dyno comparison that holds more testing variables constant.

Here you go.

[Shiv@Openflash]

Originally Posted by jamesm

i don't know what you mean by 'MAP is a load estimate'. Load is a load estimate. MAP is manifold pressure. I agree that MAP is only one factor contributing to engine load... hence why when trying to limit manifold pressure you'd want to use the MAP sensor, not load.

i can't see the advantage of an ignition/load-based strategy over one that actually cuts fuel based on manifold pressure. different stroked for different folks, i guess...

MAF is a better indicator of engine load than MAP. Take a turbo engine that is running wastegate spring pressure. Then go catless with a test pipe. The reduced exhaust restriction (and higher airflow/engine load) will be seen by a MAF sensor. It will go unnoticed by a MAP sensor. Different strokes indeed

[jamesm]

Originally Posted by Shiv@Openflash

MAF is a better indicator of engine load than MAP. Take a turbo engine that is running wastegate spring pressure. Then go catless with a test pipe. The reduced exhaust restriction (and higher airflow/engine load) will be seen by a MAF sensor. It will go unnoticed by a MAP sensor. Different strokes indeed

But you're not trying to implement a load cut. You're trying to implement a boost cut. I don't see what you're getting at there. It's pretty simple: you want to limit manifold pressure... you use the thing that senses manifold pressure. I get the point that load and manifold pressure correlate somewhat and that factors other than increased boost can result in increased load, but isn't that exactly what you don't want to respond to if you're trying to implement a boost cut?

In any case.. i'm glad that you've found a way around it, even if we disagree on the implementation details. It will certainly save an engine... and at the end of the day that's what matters.

[Shiv@Openflash]

Originally Posted by jamesm

But you're not trying to implement a load cut. You're trying to implement a boost cut. I don't see what you're getting at there. It's pretty simple: you want to limit manifold pressure... you use the thing that senses manifold pressure. I get the point that load and manifold pressure correlate somewhat and that factors other than increased boost can result in increased load, but isn't that exactly what you don't want to respond to if you're trying to implement a boost cut?

In any case.. i'm glad that you've found a way around it, even if we disagree on the implementation details. It will certainly save an engine... and at the end of the day that's what matters.

No. The intention was to implement a load cut. This protects against wastegate failure or any other condition that would cause an overboost.

As an aside, the Denso logic makes this quite effective since engine load isn't just a raw MAF value but rather an engine speed (/rev) corrected load variable. So adding a breakpoint just above the desired engine load and then another one just above that and mapping in substantial ignition retard does the job very well. Arguably better than a rather simple MAP induced cut which is oblivious to any thing that would change engine VE and result in a condition where the ECU sees same nominal MAP value with vastly different engine load.

[Shiv@Openflash]

Originally Posted by transition

Here you go.

Sorry for being picky but when comparing two competent NA tunes (even a 91oct vs 93oct in this case), pickiness is required since we are not dealing with huge power differences. So not being picky and ignoring sampling bias (unintentional I'm sure) can lead the casual observer to skewed or exaggerated results.

In the dyno files you kindly provided, I tried to compare a warm 5th gear OFT off-the-shelf run to a warm 5th gear custom Ecutek run but was unable to find anything that fits the bill. So I compared the one (and only) warm 4th gear OFT off-the self run to ALL of the warm 4th gear Ecutek custom tune runs and come up with this:



Not surprisingly this is more in line with what I would expect between a good 91 and good 93oct tune (the difference in power being primarily at high RPM due to running more advance up top with 93oct). The differences everywhere else are rather minor as one would expect with an NA car already running at or near MBT. The other graphs provided involve [unintentional] sampling bias which accounted for most of the dyno differences.

And again, forgive me for getting picky but I do spend a lot of time calibrating our OTS maps. So when someone compares them to something else, I apply the same pickiness in analyzing the data as I do with creating the OTS map. Not necessarily to refute the comparison but also possibly to learn from it. So please don't take my involvement in this thread the wrong way.

Still, it would be nice for the purpose of transparency to change the graph in your original post to the one provided above. I think it is as fair as possible given the sample pool you provided. And again, thank you for being transparent and providing all the dynojet run files.

Cheers,
Shiv

[jamesm]

Originally Posted by Shiv@Openflash

No. The intention was to implement a load cut. This protects against wastegate failure or any other condition that would cause an overboost.

As an aside, the Denso logic makes this quite effective since engine load isn't just a raw MAF value but rather an engine speed (/rev) corrected load variable. So adding a breakpoint just above the desired engine load and then another one just above that and mapping in substantial ignition retard does the job very well. Arguably better than a rather simple MAP induced cut which is oblivious to any thing that would change engine VE and result in a condition where the ECU sees same nominal MAP value with vastly different engine load.

Gotcha.

[transition]

I'm convinced you should have been a lawyer.

Originally Posted by Shiv@Openflash

Sorry for being picky but when comparing two competent NA tunes (even a 91oct vs 93oct in this case), pickiness is required since we are not dealing with huge power differences. So not being picky and ignoring sampling bias (unintentional I'm sure) can lead the casual observer to skewed or exaggerated results.

In the dyno files you kindly provided, I tried to compare a warm 5th gear OFT off-the-shelf run to a warm 5th gear custom Ecutek run but was unable to find anything that fits the bill. So I compared the one (and only) warm 4th gear OFT off-the self run to ALL of the warm 4th gear Ecutek custom tune runs and come up with this:



Not surprisingly this is more in line with what I would expect between a good 91 and good 93oct tune (the difference in power being primarily at high RPM due to running more advance up top with 93oct). The differences everywhere else are rather minor as one would expect with an NA car already running at or near MBT. The other graphs provided involve [unintentional] sampling bias which accounted for most of the dyno differences.

And again, forgive me for getting picky but I do spend a lot of time calibrating our OTS maps. So when someone compares them to something else, I apply the same pickiness in analyzing the data as I do with creating the OTS map. Not necessarily to refute the comparison but also possibly to learn from it. So please don't take my involvement in this thread the wrong way.

Still, it would be nice for the purpose of transparency to change the graph in your original post to the one provided above. I think it is as fair as possible given the sample pool you provided. And again, thank you for being transparent and providing all the dynojet run files.

Cheers,
Shiv

[Shiv@Openflash]

Originally Posted by transition

I'm convinced you should have been a lawyer.

How so?

[transition]

Originally Posted by Shiv@Openflash

How so?

/thread

[Shiv@Openflash]

Originally Posted by transition

/thread

In my opinion, the thread isn't done until that dyno comparison in your first post is replaced with something fair and valid for the reasons I took the time to politely and clearly explain earlier.

Shiv

[steve99]

Agree this thread has seen a lot of good info revealed and sensible logic based debate.

I have learned much from this so thanks to all