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Old 11-17-2016, 09:15 PM   #31
e30davie
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I appreciate the DIY nature of the idea. Although there are definitely "better" ways to achieve your goals, there is something to be said for tinkering in the shed with cheap stuff solving problems and modifying it beyond its original intent just for the sake of it. All the power to you!
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Old 11-17-2016, 09:43 PM   #32
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Thread turned so positive! <3

While yes, there are classes that can't change the ECU, many of them can, but to keep the playing field equal, they all have to run the same tunes.

I also strive to do an entire tune and very cringe when people ask, "how much power did it make?" when you know for a fact they are asking for peak numbers. Clearly in the photobucket link I posted, you can see the power under the curve was greatly increased where the peak only moved a bit - the after was a totally different car. npavlo is so correct in many ways and not arguing the fact that a stock ECU with a stock flash replaced with a stand alone will increase power, but to be fair, you would have to first re-map the stock ECU to make apples to apples.

After all, fuel calibration and spark tables the engine likes won't change because your hardware did, and you hit the nail on the head with your other statement. OEM is very reserved since they will be warrantied and have to follow a strict guideline for emissions - in fact modern cars MUST be proven to be emission compliant for at least 100k miles. That being said, you can expect to win a marathon when your opponent has his shoe laces tied together because the gov't said so. Cummon, man, NASCAR still uses a venturi carburetor and makes 110hp/cyl from a mere 4" bore - why? Because they are dead reliable and do the job. In racing situations where you are either on or off the throttle, transients, dive-ability and comfort matter little.

As far as my alpha-N, it is not limp, and not using limp maps, retained variable cam timing etc. The car runs and drives like stock. The thing about stock ECU's is you can manipulate the math, locations, pointers, but you are also correct that they are limited. The MAF tables are ignored and maps are based solely on throttle. (Bosch Motronic 3.x)

I tried tricking the Motronic 1.x into running ITB's, but it would only work in a race car, just absolutely horrible on the street. It was just plain too dumb/slow/ancient, but can't say I didn't try. The chip files had to be too small and lots of silly math was created to get all the information small enough the ECU could read it quickly enough for "real time" in the day. Perhaps if I could rewrite the assembly, it would have been easier, but in the end it I stuck a Microsquirt in. The early Bosch stuff did have a pressure sensor, but not such that could be tied into the maps.

As far as the SD conversions I have done, they are real conversions, but I was not part in that development, just an end user. But, those systems have a MAP sensor that was only used for baro/elivation correction - the PCM was never reliant on them for mapping in OEM configuration. I wish I was fluent enough in raw binary to have done it myself.

With emulation, you CAN tune a stock ECU n the fly, but you're not going to do it with a $20 cable and USB port.

Nice to hear experiences from other tuners. BMW OBD1 was voodoo for quite some time, unlike the open sharing we had with GM, many people working on disassembly and now those old ECM's can be manipulated to do just about anything. I see the BMW OBD2 stuff is heading that direction and it's refreshing, and I encourage it. Apologies for ranting earlier, but "just throwing it away" isn't always the best for every situation. As mentioned, one can play with the stock ECU's for very little investment.
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Old 11-17-2016, 09:48 PM   #33
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Originally Posted by berlow94 View Post

But today you can buy a $1.1k ecu that is superior in every way to using the stock DME!!!
I missed your post about the dyno results, the quotes must have been mixed up. You still are not comparing apples to apples. You would need to tune each of those scenarios one after another to be fair in saying the computer hardware alone made the difference. It's not fair to compare a mail order tune to a live tune - that's clearly shown in the link I posted of my dyno graph. If you brought your car to TRM/Technica, had them tune on the dyno, then plugged the aftermarket in, you would have a fair comparison.
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Old 11-17-2016, 10:02 PM   #34
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I'm learning so much.
So who here wants to polish the loose ends of my Megasquirt tune on my m20 turbo? lol

I'm sure there are plenty of members that would look at your logs, but best to find your MBT on a dyno.
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Old 11-18-2016, 12:22 AM   #35
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I'm sure there are plenty of members that would look at your logs, but best to find your MBT on a dyno.
I could do that. I want to change the clutch before hitting the local (40mi out) dyno so i can take full advantage of tuning since I need EBC tuned as well.
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Old 11-18-2016, 07:51 AM   #36
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How often are cars on a circuit at WOT (laying down those mad numbers from dyno sheets)? Not as much as people think. So getting things like overrunning, part throttle, transients are major reasons why people hire me to do their cars. I did a car that dropped two seconds on a 1:20 lap just from fixing that (peak power was the same). The car drove so well the driver could start concentrating on analyzing how to make the car go faster in other ways (suspension, aero, etc). I could have charged him 10x more than I did that's how happy he was. Obviously I didn't, I just did a proper job that I was paid to do.

ForcedFirbird example of Motronic 1 trying to get it to run with ITBs validates what I am talking about. What kind of race car was that? Hopefully not something needed to be driven at part throttle (running badly). In fact, almost every time a 24v blows on a road course it almost always happens during maintenance throttle, NOT WOT. The place where nearly NO ONE touches mapping wise (with factory AND aftermarket). This is where being able to live tune helps, but also being able to identify the what the OEM is doing to maintain emissions functions by changing timing, running lean mixtures, etc.

It is just so much more painless to go aftermarket now, especially on a project with drastic changes like ITBs. Even if you have to wire in.

ForcedFirebird, for speed density with ITBs, you can still run a MAP input so the ECU has a reference for air density with vacuum, you just have to be creative with how you span your axis of your maps (obviously with a GOOD aftermarket ECU). This is how I do S50/S54/S62/S65/S85. It works so good that with the more advanced ECUs I can calculate fuel consumption per lap down to 0.01L resolution.

There is all kinds of other dangerous things that happen with ITBs regarding ignition tuning though. Running a "plenum" ignition map with ITBs will not work, especially at part throttle....

This thread has sparked some good discussion, but unfortunately it has the potential to spiral out of control more and more especially if we start talking more deeply about strategies for mapping.
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Old 11-18-2016, 12:56 PM   #37
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Quote:
Originally Posted by npavlo View Post
Hi.

Nothern,

MS41 is decent. There are fundamental things you can't change though I believe. Like, how would you go to speed density (for real, not a limp table - stop calling it Alpha N like it was "supposed" to be like that - like it is some "secret" mode)? ForcedFirebird confirmed the MAF can't read positive pressure. I highly doubt those modified MAF sensors used for turbo cars actually read TRUE air mass? PLEASE CORRECT ME if I am wrong. I would be really impressed if they did, but I am under the assumption that the input is just scaled wildly to make it "work" with the fundamental mapping that is locked. Regardless, it does not justify "forcing" the factory ecu to do what is needed when the other solutions exist - to me.
Honestly, I don't know enough about how it works or how the MAF reacts to pressurized air vs atmospheric, but the MAF logs more flow(in KG/HR) and load (Mg/Stroke) when I go into boost, and it reacts as it should as long as you don't max out anything (MAF pegs voltage ~725kg/hr iirc, also doesn't work well in Blow-thru anyway, so the "best" option to avoid this and run Blow-thru now is one of the aftermarket ford slot style mafs, which come with a MAF scalar tool so you can plug that into the ECU's maf scalar and go)


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Nothern, unfortunately this plugs only into OBD1 vanos wiring.
Kind of unfortunate, but I understand how little demand there is for M52/S52 OBD2 turbo stuff vs factory turbo cars like Evos/Subarus/Supras etc.

It probably wouldn't be too hard to open it up and reconfigure the pinout for whatever the difference is (I have no idea). Then I guess it would be all about sensors(assuming I'd need to swap out the weird OBD2 cam sensor for a normal Hall sensor)
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