7730 engine management

[The Dark Side of Will]

True enough, but so far so good. The IAT doesn't change that much in the tables run.

Well since you haven't TUNED your IAT curves, you don't know what your engine actually needs. The stock table is garbage.

The IAT doesn't change the MAF or VE tables at all, just timing. Otherwise my A:Fs would be different everyday. They aren't. And they'd have changed when I ran my Z34 on the dyno with the stock IAT, without an IAT, and with a GTP IAT. They didn't.

For the CALCULATION that derives MAF from a hot wire sensor, you ABSOLUTELY must know air temperature. Fortunately for you, this is handled directly within the sensor.

Speed density systems are DEPENDENT on IAT for the correct air density calculation. I have dyno sheets proving THIS.

As soon as my IAT is moved into the correct position, then my PCM is correctly tuned, and a change in ambient temperature won't affect my tune at all. However changes in ambient aren't affecting it as-is. I ran it this morning, 45* out, ran perfect. Drove it again this afternoon, 75, ran perfect. A:Fs didn't move at all. Ignition timing probably did, to some minute degree, as it was supposed to.

What you seem to think is a lack of dependence on IAT, I see as you having a really fat tune that just doesn't care.

Also, you didn't LOG your ignition timing today, so you don't KNOW what your ignition timing did. Any claim you make about it is a Wild Ass Guess (WAG) straight out of ignorance.

[Aaron]

Well since you haven't TUNED your IAT curves, you don't know what your engine actually needs. The stock table is garbage.

Stock timing is garbage? Is that why even the best chips gain, maybe 5hp?

For the CALCULATION that derives MAF from a hot wire sensor, you ABSOLUTELY must know air temperature. Fortunately for you, this is handled directly within the sensor.

Speed density systems are DEPENDENT on IAT for the correct air density calculation. I have dyno sheets proving THIS.

So for my system, it makes no difference on airflow calcs.

The dyno sheets I referenced above, no changes in the A:F ratio. There were changes in power, to the tune of 10-20fwhp, but A:F curves looked identical. This was on a speed density car.

What you seem to think is a lack of dependence on IAT, I see as you having a really fat tune that just doesn't care.

Also, you didn't LOG your ignition timing today, so you don't KNOW what your ignition timing did. Any claim you make about it is a Wild Ass Guess (WAG) straight out of ignorance.

Fat as in how? My tune is close to dead on. Idle is 14.7, decel pegs lean, and the most recent changes to the boost curves brought it to a flat, stable, 12:1 from the second I go WOT, to fuel cut. It's perfect. And it is the same way no matter what the temperature. I also smoothed out my transition from vacuum to boost at partial throttle, and got these damn good as well. The only other change I'm going to make is to shift the WOT curve up to 12.5. I'm not sure how you can call this "fat", but you know so much about my car, why don't you tell me how. Because I noticed you were the one tuning it, looking at every datalog it has.

How do you figure I didn't log my timing? I carry a scanner with me, and have it plugged in and running, everytime I leave my driveway. And it is a logging, and graphing, scanner. Furthermore, my WBO2 also datalogs everytime I go WOT, automatically, on internal memory. I log everything that happens with my car, everytime I drive it. When I stop changing things, I'll stop logging.

And I'm the ignorant one?

[Series8217]

Well since you haven't TUNED your IAT curves, you don't know what your engine actually needs. The stock table is garbage.

Stock timing is garbage? Is that why even the best chips gain, maybe 5hp?

It's complete garbage. Your motor is not stock.

[Aaron]

It's working well so far. Fast as hell.

When I get the inclination, I'll start advancing timing and see what it does.

[The Dark Side of Will]

Stock timing is garbage? Is that why even the best chips gain, maybe 5hp?

On a stock engine they might, but you're running different octane and different chamber pressures/temps than stock.
Like Steven said, you're not stock, so that part of your tune isn't applicable.
But you can't use your piggy back to mess with timing, can you? Why don't you just spend some more money on an MSD boost retard box?

So for my system, it makes no difference on airflow calcs.

The dyno sheets I referenced above, no changes in the A:F ratio. There were changes in power, to the tune of 10-20fwhp, but A:F curves looked identical. This was on a speed density car.

Then it's pretty fortunate for you (and a hell of a lot of other tuners who also have no idea how the ideal gas law works) that GM decided that their MAF sensors should have integral temperature compensation. They could have done that in the PCM's...

I'll @$$ume, due to your background, that these dyno sheets you reference are from 3.4's. 20 wwhp on a 200 chp engine is more than 10%. Yeah, the IAT is completely superfluous.

It's so superfluous that my Northstar car ran 13.2 @ 102 with the IAT unplugged and 12.86 @ 106 with the IAT plugged in.

Fat as in how? My tune is close to dead on....

You're not talking about knock counts, so you're so far from the ragged edge that it basically doesn't matter what you do. You're stumbling around in the middle of a dark room and think that there are no walls just because you haven't found any yet.

How do you figure I didn't log my timing?

Ignition timing probably did, to some minute degree, as it was supposed to.

The only reason you'd say "probably" is if you didn't know. Hence, even if you did log it, you didn't look at the logs. And how many logs do you have to look at? ECM? Piggyback? How do you integrate that data to get a meaningful picture of what your engine's doing?

And how much is ignition timing supposed to move? It ought to move more than a minute degree or you'd run 30+ degrees at idle and kill the engine every time the A/C compressor kicked on.

[Aaron]

On a stock engine they might, but you're running different octane and different chamber pressures/temps than stock.
Like Steven said, you're not stock, so that part of your tune isn't applicable.
But you can't use your piggy back to mess with timing, can you? Why don't you just spend some more money on an MSD boost retard box?

Again, Will talking about shit he doesn't know. I can adjust timing. I can advance or retard, under all conditions, 20* in either direction.

I'll @$$ume, due to your background, that these dyno sheets you reference are from 3.4's. 20 wwhp on a 200 chp engine is more than 10%. Yeah, the IAT is completely superfluous.

It's so superfluous that my Northstar car ran 13.2 @ 102 with the IAT unplugged and 12.86 @ 106 with the IAT plugged in.

I'm not arguing its affect on power, I'm arguing its affect on A:F. What were your A:F's on those runs? Because mine were identical, run after run.

You're not talking about knock counts, so you're so far from the ragged edge that it basically doesn't matter what you do. You're stumbling around in the middle of a dark room and think that there are no walls just because you haven't found any yet.

I already told you, there isn't any knock. It's hard to tell you about knock counts when, well, there aren't any. That's why I'm not pulling timing with boost. I could advance the timing and find some, but I want to get my A:Fs dead on first.

The only reason you'd say "probably" is if you didn't know. Hence, even if you did log it, you didn't look at the logs. And how many logs do you have to look at? ECM? Piggyback? How do you integrate that data to get a meaningful picture of what your engine's doing?

And how much is ignition timing supposed to move? It ought to move more than a minute degree or you'd run 30+ degrees at idle and kill the engine every time the A/C compressor kicked on.

Ohhh, so first it was, "none of your shit can log", and now its, "you don't look at the logs." You think I bought, and use, all this expensive datalogging shit to ignore?

Will, you truly are a fucking retard sometimes.

[Aaron]

For the sake of keeping this thread educational.

I think it's well proven at this point that Will doesn't know shit about the advantages and disadvantages of my piggyback. There simply is not a better alternative, short of reprogramming the entire PCM with boost coding, maybe from a 95 era 3800 S/C. But I'm not willing to pay for someone to completely redo the entire PCM with an engine it wasn't designed to run, a pressure system is wasn't designed to use, and a transmission from the equivalent stone age. It isn't practical.

The piggyback, unlike your stand alones, takes advantage of every factory code, and lets the PCM work just like it did stock. It just allows you to tune it. Every sensor still works as designed, and nothing changes. The PCM just now knows how much air the engine is getting, and will add the according amount of fuel. Hell, I'm even using stock fuel tables. I'm just changing which one the PCM chooses to use. That's why my adjustments don't change much with RPM.

There is one problem with my piggyback, and if I may say so myself, it's significant. It does not have an ambient pressure adjustment. As soon as my engine goes into boost, my PB starts adjusting the airflow values, and by 2psi, is doing so at a pretty significant rate. This works perfectly. However, as soon as I drop or gain a noticeable altitude, it throws it off. For example, I drove to Pueblo a couple weeks ago. Once there, some 1500ft lower than where I'm at, it throws it off. My partial throttle, and full throttle tunes were dead on. However in between was shit. So if I went to about 75-85% throttle, the vacuum gauge hovered just below 0, and the car fell on its face. What happened, is even though I' not at positive pressure, on the static pressure scale that the PB uses, I went into what would be boost at my former elevation, and the PB started adjusting airflow rates. However I wasn't in boost yet, and the car pegged lean, and made no power. This is a big damper on any sort of traveling. If I cared enough, I could carry my laptop with me, and it'd be easy as hell to fix every gas stop or whatnot. Just slide the table to the right, where my last row of 10s (Neutral) is in the ambient row (Which it shows). I just wish it'd do this automatically. I'm going to call the company, FTC1, and see if it does, because I highly doubt their product would ignore this when it takes so much more into account.

But other than this, and that in order to flash it the car needs to be off, I have no complaints. The PB was easy as hell to get setup (6 wires), and easy to tune. You can't beat that.

[The Dark Side of Will]

Again, Will talking about shit he doesn't know. I can adjust timing. I can advance or retard, under all conditions, 20* in either direction.

But *have you*? That's the important question. Since you don't know what it does and haven't looked at your logs, I'd say that's a no...

I already told you, there isn't any knock.

Which is exactly my point. You have no idea where you are relative to the edge of what your engine can handle.

You think I bought, and use, all this expensive datalogging shit to ignore?

From what you've been saying about what your ignition timing "probably" does, yeah, I think you did buy it to ignore.

[Aaron]

But *have you*? That's the important question. Since you don't know what it does and haven't looked at your logs, I'd say that's a no...

Again, Will talking about shit he doesn't know. I have adjusted the timing, and confirmed it actually adjusts the timing. Who the fuck whoulda thunk? They advertise it adjusts timing, I wire it correctly, and surprise fucking surprise, it adjusts timing.

Which is exactly my point. You have no idea where you are relative to the edge of what your engine can handle.

Just because I'm not running timing to the edge, doesn't mean I'm not pushing the engine to the edge. I don't need every degree of timing to max what I'm comfortable with. The engine feels like it's making every bit of 400+ rwhp, and I'm not comfortable with pushing it any farther than it is. I actually turned the boost back down for this reason alone. In reality, no one is running their 3.4 to the edge, because no one knows where the edge is. But my edge is around 425-450. And not like you'd know with all of your 250whp, but that makes one fucking scary Fiero.

From what you've been saying about what your ignition timing "probably" does, yeah, I think you did buy it to ignore.

What have I been saying it probably does? I know exactly what it's doing. It's doing exactly what the stock tables tell it to. Unless GM lied to us, and the stock timing tables and scanner aren't really what it's doing. I should put a timing light on it....

Will, I no longer want you posting here. You have absolutely no fucking clue about my setup still, and are arguing points that don't even matter. When you actually learn something about the piggyback I'm running, or any piggyback for that manner, then say something. Because the only person who has first hand experience with this piggyback is ironically the only person who knows its faults. You don't. You've been wrong at nearly everything you've said here.

[The Dark Side of Will]

I have adjusted the timing, and confirmed it actually adjusts the timing.

That's a basic verification test. That is trivial. You're proud of that? That's second grade, dude, right after you learn your ABC's. That is not dialing your timing curves.

What have I been saying it probably does?

A:Fs didn't move at all. Ignition timing probably did, to some minute degree, as it was supposed to.

"Probably" = you don't watch your logs so you don't know.

Just because I'm not running timing to the edge, doesn't mean I'm not pushing the engine to the edge.

You DO realize how ridiculous that sentence made you sound, right?

The engine feels like it's making every bit of 400+ rwhp

When's your ass dyno due for calibration? What lab do you have it sent to? Again a ridiculous unsubstantiated claim.

If you're making 400 HP, go run 10's already. Show FieroX how it's done.

From what you've been saying about what your ignition timing "probably" does, yeah, I think you did buy it to ignore.

I know exactly what it's doing. It's doing exactly what the stock tables tell it to. [...] I should put a timing light on it....

Considering that you don't know enough about ESC to know the circumstances under which reported timing may be different than actual timing, maybe you *SHOULD* put a timing light on it. Still getting that inexplicable ICM code?

We've already been over the fact that the stock tables are garbage for your application.

And what have I been wrong about here?

-You guess what your timing does because you don't watch your logs
-You have to fuck with your tune when the weather changes (ambient pressure, in this case). This was one of my very first points in this thread that got you butt hurt and started this argument.
-You're not running even close to the edge, so you have no idea where your engine is relative to that edge

So I pretty accurately predict the behaviour of the system composed of you and your piggyback, despite having

absolutely no fucking clue about my setup still

Yep, I guess I'm the ignorant jackass...
You know, "fuckwit" is an insult you don't use nearly enough.

[Series8217]

How did you even confirm that it actually adjusts the timing?