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Old 10-30-2009, 02:17 PM   #101
MRF582
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Originally Posted by Clark Turner View Post
760 before 800 now

Clark
JSarv, are you reading this? Were you not complaining earlier about this ROM not having enough resolution for higher power levels? Are you at even HALF of this power level?

Thanks Clark cutting the BS once again.
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Old 10-30-2009, 06:15 PM   #102
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760 before 800 now

Clark
Wow! Impressive!

Wait...your not kidding with us are you?
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Old 10-30-2009, 08:56 PM   #103
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Originally Posted by MRF582 View Post
JSarv, are you reading this? Were you not complaining earlier about this ROM not having enough resolution for higher power levels? Are you at even HALF of this power level?

Thanks Clark cutting the BS once again.
not this rom *******...

The maf based roms.

There is currently 1 little spot that I could use more resolution, again I'm a nut about not having any dips in closed loop/open loop transition.



Btw Clark - congrats on getting it to work, now if you figure out any secrets.... you should PM me to let me know.

I have noticed that there is less after firing on my car with this rom @ any timing/afr. I can't hardly get it to afterfire - and when it RARELY does its a violent one..

From what I read (in my new book) ignition dwell could be causing a more complete burn.

I have also talked to someone that suggested that we need less dwell than subaru OEM ecu's offer..
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Old 10-30-2009, 09:20 PM   #104
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not this rom *******...

The maf based roms.

There is currently 1 little spot that I could use more resolution, again I'm a nut about not having any dips in closed loop/open loop transition.
Dude, clearly you are a flaming n00b. You were arguing your whole point about not having enough resolutions in the fuel map on a MAF based ROM? Jesus H freaking Christ. Holy ****! Please put down the USB cable and step away very slowly. Like seriously, stop tuning **** or at the very least stop posting on this BBS so other n00bs that are even n00bier than you won't read what BS you have to say and think it's even halfway legit.

Let me explain. In a MAF based car, you tell the ECU what AFR you want to run. Then the ECU calculates the appropriate pulsewidth based on what the MAF sensor tells it how much air is entering the engine. If you think the AFR table needs more resolution then you CLEARLY don't understand how MAF works. There are many MANY tables that govern the 'final afr target'. In my ROM, there's a table that delimits the minimum AFR to 12.98 if I'm above 88% TPS no matter what the Fuel Table says... For SD, I can see you argument slightly but in a MAF based car, it doesn't matter what the VE of the engine is!!!!!!! Air in = air out unless you have a leak in the system. The MAF measures air in! So if that is dead on, how the **** can anything else be off in terms of fueling? It can't, unless there are other maps that change the internal logic of the ECU that tells it to target a different AFR than what the OL Fuel Map calls for. Like the example I posted. On a MAF based car, I can confidently say that I can tune to any power level with an Open Loop fuel map that has only 4 cells in it. And if you don't see it then... HOLY ****! Stop posting please! There's enough misinformation on NASIOC as it is. Don't add to the BS.

But seriously, I cannot FREAKING believe I wasted my precious time trying to educate your worthlessness. Good bye!

Also, no ****, a SD ROM has less backfire than a MAF based ROM... Do you even somewhat understand the underlying principles? Because the caliber of your posts offer no such supporting evidence.

Last edited by MRF582; 10-30-2009 at 09:26 PM.
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Old 10-30-2009, 10:00 PM   #105
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Originally Posted by MRF582 View Post
Dude, clearly you are a flaming n00b. You were arguing your whole point about not having enough resolutions in the fuel map on a MAF based ROM? Jesus H freaking Christ. Holy ****! Please put down the USB cable and step away very slowly. Like seriously, stop tuning **** or at the very least stop posting on this BBS so other n00bs that are even n00bier than you won't read what BS you have to say and think it's even halfway legit.

Let me explain. In a MAF based car, you tell the ECU what AFR you want to run. Then the ECU calculates the appropriate pulsewidth based on what the MAF sensor tells it how much air is entering the engine. If you think the AFR table needs more resolution then you CLEARLY don't understand how MAF works. There are many MANY tables that govern the 'final afr target'. In my ROM, there's a table that delimits the minimum AFR to 12.98 if I'm above 88% TPS no matter what the Fuel Table says... For SD, I can see you argument slightly but in a MAF based car, it doesn't matter what the VE of the engine is!!!!!!! Air in = air out unless you have a leak in the system. The MAF measures air in! So if that is dead on, how the **** can anything else be off in terms of fueling? It can't, unless there are other maps that change the internal logic of the ECU that tells it to target a different AFR than what the OL Fuel Map calls for. Like the example I posted. On a MAF based car, I can confidently say that I can tune to any power level with an Open Loop fuel map that has only 4 cells in it. And if you don't see it then... HOLY ****! Stop posting please! There's enough misinformation on NASIOC as it is. Don't add to the BS.
Your going to tune a maf based FI car on 4 cells? I'll pay alot of money to see how ****ty that thing drives. If your talking WOT - Its possible, but best not let off the gas.
It just so happens that an RPM/MAF setup would be ideal, unfortunately Subaru uses a 2d maf setup - this serverly limits us on a well rounded tune. Wot was great in my car on maf. I could keep a pretty tight afr. CLosed loop <14.7 PSIA was terrible. Cold start was terrible. Throttle response was terrible. If you don't like it go somewhere else.

If I'm misinformed you should email Greg Banish and tell him he's a ****ing idiot/liar who should not publish a book. I finished it tonight and have changed my opinion on some things. But based on his inputs maf based systems that have use a 3d based maf mapping are superior to SD based EM. However, this is not an option.
But seriously, I cannot FREAKING believe I wasted my precious time trying to educate your worthlessness. Good bye!
I called the wambulance, they're busy.

Also, no ****, a SD ROM has less backfire than a MAF based ROM... Do you even somewhat understand the underlying principles? Because the caliber of your posts offer no such supporting evidence.
Do explain.. late combustion/left over fuel is what causes an afterfire, no? So when I'm running rich with little timing, does my engine know I'm not running a maf based tune? Are you refering to tip out? I'm pretty sure I can make my tip out worse on SD by simply changing a few cells.
haha I have no clue what I'm doing.. 15+k miles 340+g/s on a 205...(115k miles on the clock)....... I've been tuning my car for 2 years through its mods and just for learning sake. I've been tuning the barbaric Hondata on my Civic for more than 2 years now, well I tuned it for each season and have a map for each season.

So... Go cry somewhere else.


-jerod

Last edited by JSarv; 10-30-2009 at 10:06 PM.
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Old 10-30-2009, 10:18 PM   #106
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It just so happens that an RPM/MAF setup would be ideal, unfortunately Subaru uses a 2d maf setup
So the equation for engine load is what? And what does the Open Loop fuel map look like? Oh yeah! 'engine load' (a function of MAF) versus RPM... hahahahhaa, Keep digging that hole! You do realize that "CLosed loop <14.7 PSIA was terrible. Cold start was terrible. Throttle response was terrible." has NOTHING to do with the Open Loop Fuel Target map... Blame that on your poor tuning skills. Tune warm-up enrichment, cranking, base idle timing, tip-in enrichment, tip-in enrichment compensations...

hahahaha, you have SO much to learn about tuning a Subaru ECU. Knowing the basics of EFI tuning as your buddy Greg Banish has suggested is good. But that's not even close to enough to be able to fully map a Subaru ECU...

Also, afterfires occur on a MAF based system when metered air leaves the system before entering the combustion chamber like when a vent to atmosphere BOV opens. On a SD system, there is no such loss as long as theyre's no leak between the manifold and the cylinder head...

So you've been tuning for the past 2 years? Oh, LOL! I've been tuning for the past 4-5 years. Does that mean I know twice as much as you? No actually, I know much more than that! LOL!

I love the internet. So entertaining thanks to characters such as yourself. Good luck dude! You're gonna need it! Clearly you know more than the typical 'tuner' we get around these parts but still, you are WAY too overconfident in your techniques. Understand that there are something things that you are just wrong about. Even if it's said by someone who hasn't published a book. And if you're trying to say that publishing a book somehow makes you a subject matter expert then you have a LOT to learn in life overall.

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Old 10-30-2009, 10:52 PM   #107
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Originally Posted by MRF582 View Post
So the equation for engine load is what? And what does the Open Loop fuel map look like? Oh yeah! 'engine load' (a function of MAF) versus RPM... hahahahhaa, Keep digging that hole! You do realize that "CLosed loop <14.7 PSIA was terrible. Cold start was terrible. Throttle response was terrible." has NOTHING to do with the Open Loop Fuel Target map... Blame that on your poor tuning skills. Tune warm-up enrichment, cranking, base idle timing, tip-in enrichment, tip-in enrichment compensations...
Oh how you are wrong..
You have a 2d table. A number based on a voltage. A voltage based on an airflow. Your telling me, without any question added that an engines final volumetric efficiency is going to be the same across the board at a given airflow?

What happens when my VE drops from a drop in efficiency (turbo, you know the thing that whistles), in theory this could be minimal, but when inhaled air continues to climb and exhausted compressor efficiency drops or airflow surpass an intercoolers ability to cool, an engines VE will drop.

SO a MAF table based on a Voltage and RPM (which MOST GM vehicles come equipped with) is MUCH MUCH more accurate than a straight 2d table that Subaru offers. If your going to argue this, YOU sire a digging a hole.

hahahaha, you have SO much to learn about tuning a Subaru ECU. Knowing the basics of EFI tuning as your buddy Greg Banish has suggested is good. But that's not even close to enough to be able to fully map a Subaru ECU...
Guess so, glad god blessed you with the overwhelming talent.

Also, afterfires occur on a MAF based system when metered air leaves the system before entering the combustion chamber like when a vent to atmosphere BOV opens. On a SD system, there is no such loss as long as theyre's no leak between the manifold and the cylinder head...
So an afterfire is just unmetered air huh? Its not unburned fuel/combustion entering the exhaust stream post exhaust valve? That amazing that air combusts...
And rich is rich... right?
So you are telling me that more resolution is crap...? Your telling me an engines VE is 100% relative to pre-compressor consumed air? An engines VE will always be linear to airflow?

That when my maf tune goes rich and afterfires, my SD tune wont afterfire because the air is metered, even though its rich?

If Subaru hit the nail on the head, why in the world is there an eventual limit that guys switch over to a stand alone? Why don't the guys making big power run open source?

Why does nearly every tuner charge a premium to tune Open Source? Why do most tuners dislike open source?

^^ Maf based...

Have you ever had a big maf intake on your car? Tried tuning <ATM PSIA?

Sure some guys have done it, but I can only imagine how "awesome" the car drove. I've drove an "awesome" driving pro-tuned WRX that drove like a pile of ****ing ****.

I don't know what your point is? My point is, I have more of an ability to make my car do exactly what I want now...

-Jerod
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Old 10-30-2009, 11:14 PM   #108
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Jerod how is the car running? I have been waiting for this month of rain the midwest has been blessed with to pass to see if I can the rest of my SD rom finished.... Clark did you have to do any load hacks ect?
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Old 10-30-2009, 11:29 PM   #109
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Jerod how is the car running? I have been waiting for this month of rain the midwest has been blessed with to pass to see if I can the rest of my SD rom finished.... Clark did you have to do any load hacks ect?
Just fine. Waiting for **** to pan out on the front mount...

Had the bpv flange welded on (tig'd) and the flange ****ing warped..

So now (if I want to install it tom. night) I have to either find a place to plane it for me, or I have to go buy a finer file and file the piss out of it until its not warped any more...



-Jerod
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Old 10-31-2009, 12:09 AM   #110
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Yeah when I fabbed my rotated kit I had a Vband flange that just warped enough to cause an exhaust leak off the downpipe... heat warp lol, mine was blowing the hot exhaust right on my TMIC....
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Old 10-31-2009, 12:22 AM   #111
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Just read that part that goes

MRF582-"But seriously, I cannot FREAKING believe I wasted my precious time trying to educate your worthlessness. Good bye!"

JSarv- "I called the wambulance, they're busy."

Hilarious seriously LOL... JSarv you the man!
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Old 10-31-2009, 12:28 AM   #112
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Yeah when I fabbed my rotated kit I had a Vband flange that just warped enough to cause an exhaust leak off the downpipe... heat warp lol, mine was blowing the hot exhaust right on my TMIC....
Ouch... Mine failed the "mouth" psi test...

I made a phone call and its getting planed tom. morning first thing. I found a tig welder (now I have to wait till christmas )

So I'm going to learn how to tig...

Anywho, I have drove it everyday for the past week 1/2 (my DD was loaned out...) and I haven't had any problems. I have about 8-12 hours of logs...

But its all a waste as my GM IAT will be here monday or tuesday..
I'm going to pick up a Universal 3bar omni power map sensor next week.

We'll see. I don't think I'm going to make it to the last Test and Tune this year at Gateway thought
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Old 10-31-2009, 08:10 AM   #113
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if, as i hypothesized and clark reinforced, the perceived power difference is due to dwell being different/longer, it should be realized that this puts more "stress" on the coil packs.

early on utec users experienced a lot of coil pack failures. dwell was also raised as a suspect. txs claimed dwell was "identical to oem ecu." there was never a definite (ie, oscilloscope) proof that was indeed the case, or NOT the case. oddly enough coil pack failures seem to be much less prevalent these days. perhaps it was fixed in a firmware revision?

nonetheless increased dwell WILL cause more power dissipation in the coil packs and WILL cause them to run hotter, POSSIBLY causing premature failure. something to keep in mind while standing in the free lunch line.
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Old 10-31-2009, 08:40 AM   #114
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also: i think the majority of issues people have with subaru MAF load systems stem from the changes which are employed in the intake tract. for example, six years ago someone with deltadash (the only available SSM logger at the time) did sample pulls with and without the intake helmholtz resonator (aka "snorkus") attached to the filter box. the pulls without the resonator showed MUCH more MAF scatter, but they also showed increased MAF in the lower spoolup regions. many people, including myself, felt the tradeoff was worth it.

likewise changes in the elbow immediately post-maf sensor, as well as changes to the turbo inlet tube, have shown differences in the MAF translation (which, at first glance, they should not, being both POST-MAF). clark himself disliked tuning different elbows, and there was a thread in which we all thought that the corrugations in the oem elbow were actually there for a REASON (to prevent turbulence from a venting oem BPV from reaching BACK to the MAF sensor).

so, however tempting it may be, pointing a finger at the MAF sensor as the source of all necessary evil is shortsighted. it is certainly my experience that tuning SD setups at higher load is simpler, quicker, more intuitive, and easier (and i said as much nearly 3 years ago in january 07: http://forums.nasioc.com/forums/show...8#post16644828 ), BUT i think it is important to know WHY and HOW maf-load systems fall short. for example, as clark considered earlier in this thread, perhaps the temporal sensitivity of the MAF sensor itself (ie, being too quick-acting), combined with non-oem intake tracts (which promote different and more intense resonances), results in MAF scatter that causes combustion chamber conditions to vary too much, stroke to stroke, triggering knock before more stable conditions would have.

in this case a simple low pass filter (series resistance, shunt cap to ground) across the MAF sensor output voltage MIGHT be an incredibly cheap and effective trick to stabilize the load reference and allow one to push a degree or two without knock.

edit: one thing that has not been verified on this group n rom image is whether or not it has the necessary obd2 registers to pass an obd2 vehicle inspection, as is used in my state of RI. this was pretty much THE reason i never jumped ship from oem ecu+utec to a standalone like the hydra years ago. if it does NOT then modifying the car to the point where it will no longer run and/or pass readiness flags to the appropriate registers on a USDM rom is going to result in a lot of trouble when inspection time rolls around for those of us with similar inspection programs.
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Old 10-31-2009, 10:58 AM   #115
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also: i think the majority of issues people have with subaru MAF load systems stem from the changes which are employed in the intake tract. for example, six years ago someone with deltadash (the only available SSM logger at the time) did sample pulls with and without the intake helmholtz resonator (aka "snorkus") attached to the filter box. the pulls without the resonator showed MUCH more MAF scatter, but they also showed increased MAF in the lower spoolup regions. many people, including myself, felt the tradeoff was worth it.

likewise changes in the elbow immediately post-maf sensor, as well as changes to the turbo inlet tube, have shown differences in the MAF translation (which, at first glance, they should not, being both POST-MAF). clark himself disliked tuning different elbows, and there was a thread in which we all thought that the corrugations in the oem elbow were actually there for a REASON (to prevent turbulence from a venting oem BPV from reaching BACK to the MAF sensor).

so, however tempting it may be, pointing a finger at the MAF sensor as the source of all necessary evil is shortsighted. it is certainly my experience that tuning SD setups at higher load is simpler, quicker, more intuitive, and easier (and i said as much nearly 3 years ago in january 07: http://forums.nasioc.com/forums/show...8#post16644828 ), BUT i think it is important to know WHY and HOW maf-load systems fall short. for example, as clark considered earlier in this thread, perhaps the temporal sensitivity of the MAF sensor itself (ie, being too quick-acting), combined with non-oem intake tracts (which promote different and more intense resonances), results in MAF scatter that causes combustion chamber conditions to vary too much, stroke to stroke, triggering knock before more stable conditions would have.

in this case a simple low pass filter (series resistance, shunt cap to ground) across the MAF sensor output voltage MIGHT be an incredibly cheap and effective trick to stabilize the load reference and allow one to push a degree or two without knock.

Very well said.

edit: one thing that has not been verified on this group n rom image is whether or not it has the necessary obd2 registers to pass an obd2 vehicle inspection, as is used in my state of RI. this was pretty much THE reason i never jumped ship from oem ecu+utec to a standalone like the hydra years ago. if it does NOT then modifying the car to the point where it will no longer run and/or pass readiness flags to the appropriate registers on a USDM rom is going to result in a lot of trouble when inspection time rolls around for those of us with similar inspection programs.
Switch back to maf based during good ol' inspection time?
I'm not going to disagree with any of that - A stable maf based system is less complicated and has a straight foreward result in measuring air density. Again this becomes an issue when air density @ the maf vs final useful air density entering the engine has greatly changed, IE lack of efficient post turbo cooling/heat soak/cams/ect.

When doing a pull from 2k to redline I used roughly 12 cells with my maf and 10-12 with speed density depending on how I taper my boost.

WOT/full boost uses nearly the same number of cells during the pull, meaning resolution as far as mapping goes (this is OL fueling vs OL fueling). But IF there is a drop in engine efficiency of any type within this pull (as I stated above) there is going to be a pumping loss and a use for less fuel. Since we use a turbo to force air and it is directly/indirectly related to engine efficiency, it may or may not reduce the amount of air pulled through the maf sensor. In some cases I do believe this can cause an overly rich condition JUST during this event. I do believe though, since VE is not something that suddenly and unexpectedly rises without notice, rather it will drop due to heat, a maf will "somewhat fail" toward rich due to the drop in VE.

I have a few friends with Corvettes and for arguments sake took a look at some of their programming. Their maf setup uses a 3d map - laying it out as V vs. RPMS...

This creates the ability to compensate for some VE drops across the board. I do believe this would be a much better setup for Subaru's.

Not trying to argue, just saying in comparison to others, our maf layout is lacking a bit.

-Jerod
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Old 10-31-2009, 12:20 PM   #116
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Quit arguing and get tuning guys , wasted effort here.... "He who think he knows all , has very much to learn..."
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Old 10-31-2009, 01:57 PM   #117
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While I do think much of this stuff is very informative, I somewhat agree with the OP. Tune, then post before and after results.

Jerod, if you get any useful tidbits from Clark, can you please share them with the community? We'd all appreciate it.

I haven't tried it yet due to all the back and forth talk about whether or not it's worth it to go to SD and I am still a little confused on how the SD curve should look. Should it mimic your curve Jerod or should we start off with what WRXSTI-I suggested in the RR forum?

"pretty good base SD table going by using a single value for each column from where 0psi is for your location (mine is 14.7abs) and go from there."

Clark, where did you start off on this?
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Old 10-31-2009, 02:15 PM   #118
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You need to be able to tune your car from scratch to use this SD rom.... Plain and simple.

Here is my best explanation.

Maf based systems meter the amount of air ingested into the engine based on density/volume. A maf sensor should not need to be compensated for intake air temperature changes, when you see a compensation this is more for the engines volumetric efficiency @ a given temperature. << Last sentence is my thoughts on it.

Speed density does not know how much air is ingested nor the density. It simply knows the pressure at which the manifold is at. You, using the speed density load compensation map and intake air temp compensation determine the density of the air at a given manifold pressure in absolute form.

Your speed density map should look relevant to your engines VE at a given manifold pressure. Below 14.7psiA your peak torque is going to be a higher value because of cam design and general engine design. Using speed density YOU must determine the airflow and density of the air.

In the end the same value is used to determine fuel injector pulse width, Grams of air per revolution. In the end that is simply all that matters, using SD is just using a different sensor and a different approach to determine how many grams of air per revolution you are at.

-Moar..

-Jerod
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Old 10-31-2009, 02:28 PM   #119
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12.07@115.9mph-EJ205

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You need to have a fain idea of your peak torque. You need to have a faint idea of your engines VE - Knowing the efficiency range of your turbo/air it moves/and efficiency of your engine can almost spit numbers out with enough equations.

In boost, depending on your turbo, peak torque should be between 3500-4500 rpms on an EJ205. Look at old logs, instead of looking at the maf - look at the engine load vs rpm vs map. You'll notice as rpms rise so does the map and so does engine load. It may peak or it may hold for a bit but it slowly tapers towards redline (or quickly depending on your turbo). So knowing this and using that spreadsheet I made, in boost you know that your peak torque comes at X rpms, so that will obviously have the highest number in the column. As the rpms go on, unless you have big cams or a big turbo, that number should slowly diminish towards redline. This is saying that as you near redline your VE is dropping.

Out of boost, below 14.7 psiA, your peak value should start very low at a low manifold pressure as you near 14.7psiA it will slowly climb towards your peak torque. So your peak numbers should make a somewhat steady line from 2800ish (VERY low MAP) to your peak torque (mine being 4400 rpms)

At low manifold pressures there is a ton of pumping loss, an engines ve is terrible and throttle position must be taken into account.

It should look like a mountian peak/flat top from 2800ish to 4400ish as the map rises. It could be lower or it could be higher depending on your modifications... << VERY important.

Your timing map should be inversly proportional to your SD map. Meaning where you are very efficient, your timing will be low. Where you are not efficient (a - number or the lowest value) your timing will be high.

Not to be a dick but inversly proportional means 1 = -1, 2= -2, 3 = -3, ect.

As your engines efficiency rises, typically (NOT always) cylinder pressures rise. When cylinder pressures rise, flame front speed increases (takes less time from spark to flame front reaching the cylinder wall, or peak cylinder pressure from combustion). You would obviously drop timing to keep your peak cylinder pressure in check. At low loads, since the engine is so inneficient more timing is needed as flame speed slows.

^^ is the best I can do for you. I'm sure (no pun) Ken can tidy that up a bit but that is my take on it.

Again there really is nothing wrong with maf based, its actually more efficient in determining air density. However, keeping a laminar flow over the sensor and having the amount of resolution SOMETIMES needed to keep fueling in check from fire to fire is not an option for us.

I'm not going to say that SD would benefit anyone with a stock turbo/inlet/intake in any way shape or form. However, someone (like me) who has a 3" turbo inlet, 3" compressor inlet, and needs nearly 80mm of maf housing size to keep from maxing out a sensor, it will greatly benefit.

I'm going to be testing it out again on a guys 2002 WRX with basic stage 2 bolt ons. If I cannot make it any smoother in any way its going back to maf and staying for CEL purposes.

I'm willing to bet the maf tune stays...

-jerod
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Old 10-31-2009, 02:32 PM   #120
JSarv
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12.07@115.9mph-EJ205

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The easiest way to understand it is.

Your SD chart will reflect your torque curve at a given manifold pressure.

Your Ignition timing will look opposite of this.


-Jerod
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Old 11-08-2009, 12:20 PM   #121
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That makes sense.

So how's your car running?
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Old 11-08-2009, 12:34 PM   #122
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right now I'm having some weird issues with both final base fueling and my coolant system........

I either have a blockage in my coolant system or I have a cracked sleeve..

-Jerod
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Old 11-08-2009, 06:10 PM   #123
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Originally Posted by TDagen View Post
Quit arguing and get tuning guys , wasted effort here.... "He who think he knows all , has very much to learn..."
I posted on the romraider site about finishing up the tune on my car (for the most part) with this rom. I just need to get time to put it on the dyno and finish the timing map and up the boost a little more. I left the afr rich so it will be less to dial in when I crank the boost up a little more. Hopefully the afr will fall right where it needs to be with the increase in boost.

By the way, The speed density load comp table should resemble a 3-d graph of your map numbers (to put it simply). Its just tuning!! Not rocket science!

I posted my rom up and also an Airboy dyno sheet. My car really is much more easily driven around town now. I have around 3000 miles so far on this rom. I had a few issues while tuning but they where utec (first time tuning one) related and had nothing to do with the sd rom on my car.

I made 420hp on the maf tune and the way it looks I will be the same or maybe a little more on this rom when Im done. We will see.
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Old 11-11-2009, 06:02 PM   #124
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Interesting discussion.

The 40whp increase can easily be explained by the per cylinder timing compensations. I've done this before in airboys dyno......went out and logged and came back and was shocked to see i was making 40whp less.....I forgot that i put the timing comps back in my daily driver map.

it pulls 3* of timing out.....which can easily be the majority of the 40whp.

My thought on this at the moment are that it seems like a pain in the ass for no power gain. I guess I have to experience the "easier to drive the car around town" part for myself but that just seems weird. Are you talking about off boost driving? Transitions? I know its hard to describe but what exactly are you talking about? To me driving around town is closed loop driving so what exactly is better? its just smoother?

But since ur running E85 and probably a crapload of timing everywhere and easily at mbt without any knock, then who really cares about the AFR jumping +-0.5? Do you think you're missing out on power cause you cant get it consistently lean?

My car jumps the same +-0.5 AFR all the time. When my AFR leans/riches during a WOT pull it shows no discernible change in power......

The fueling in the ecu is the biggest pain because of all the per injector compensations, maf compensations, and timing comps. The injectors are setup to add pulse width (IIRC) per injector and i think 2 of them are the same just like the PC timing. So if you go from 500cc injectors to 740's, 850's or 1000's you just totally threw off that comp, our bigger intakes threw off the MAF comps, and our fuel rails,porting, and tuning threw off the need for the timing comps.

And who tunes the IAT timing comps? Do you guys really sit and let the IAT's reach 100* + and then tune the timing? Then let the temp go to 120* and retune, 140 retune all the way up to 200*?

I pretty much gave up "fine tuning" because i just dont believe in it anymore. I just changed my AVCS and timing maps in my car to s203 timing and avcs stock maps and did a pull and made the same power.

Now if i want 30whp more i'll do the smart thing and just buy the next biggest turbo.

Last edited by Phatron; 11-11-2009 at 06:08 PM.
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Old 11-12-2009, 03:32 PM   #125
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Quote:
Originally Posted by JSarv View Post
Had the bpv flange welded on (tig'd) and the flange ****ing warped..



-Jerod
off topic i know, but did they bolt it down when they welded it? when tigging stuff, we always bolt down flanges so that they have a lower chance of warping. it helps dissipate the heat alot when you bolt a flange to a huge hunk of metal.

when fixing things that are warped, i clamp it to the belt sander with some quick clamps and let the belt sander make it flat

M@
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