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Old 09-14-2008, 04:19 PM   #51
watchunglava
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Quote:
Originally Posted by Troganin View Post
I just bought the op 2.0 for this fix. Its always bothered me when I lurch the car like I've never driven stick while trying to drive "responsibly". Thanks for the good work I'll post my thoughts after I implement.
exactly like your letting bog out and then slipping the clutch or something. i wonder if it has something to do with the ivals?

what would be awesome is if we could have the high lift valves through the entire rpm range and be able to tweek that the same way you can with the pedal. i would want constant high lift except under 4k in 5th for highway travel economy. then i could really mess with this pedal cause i could keep it in the power band at all times.

anyone know how to do that? or do i need custom cams to accomplish?
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Old 09-14-2008, 05:22 PM   #52
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Quote:
Originally Posted by watchunglava View Post
exactly like your letting bog out and then slipping the clutch or something. i wonder if it has something to do with the ivals?
The ECU cannot flip from running to idle and back smoothly - according to williaty it's inherent in the system. You can't tune this out. It will be easier to control with a less sensitive pedal.

Quote:
what would be awesome is if we could have the high lift valves through the entire rpm range and be able to tweek that the same way you can with the pedal. i would want constant high lift except under 4k in 5th for highway travel economy. then i could really mess with this pedal cause i could keep it in the power band at all times.

Won't work. The switch from the factory is done generally at the point where the torque available on each cam profile crosses. Changing the point where it switched would only be detrimental to performance.

At low RPM, you want little overlap and low lift - the low lift, i think, keeps the intake velocity up which promotes good fuel mixing. More overlap would just end up pissing fuel out the tailpipe as both valves would be open at the same time.

At high RPM, you want more overlap and lift, the lift to allow flow and the overlap to allow the air's inertia to slam it into the cylinder, as well as to allow scavenging (the inertia of the exhaust creating a low pressure zone after the cylinder which draws more intake air from the other side....).

Last edited by sniper1rfa; 09-14-2008 at 05:28 PM.
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Old 09-15-2008, 04:25 PM   #53
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This thread makes me cry.
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Old 09-15-2008, 04:40 PM   #54
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Quote:
Originally Posted by williaty View Post
This thread makes me cry.

in a warm fuzzy way or a dirty, violated in the shower way?
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Old 09-15-2008, 04:45 PM   #55
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Originally Posted by Sir-Knight View Post
in a warm fuzzy way or a dirty, violated in the shower way?
... with a sandpaper condom
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Old 09-15-2008, 05:41 PM   #56
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thats helpful wility all smug cause you know more than everybody but too scared to take on the liability of tuning someones ecu.

please enlighten us ohh mighty subaru ecu god. what is it exactly that makes you feel like you have a sandpaper condom?
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Old 09-15-2008, 06:55 PM   #57
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Quote:
Originally Posted by williaty View Post
This thread makes me cry.

Am I wrong? Did I **** something up?


Great, you know a lot about the engine. If I'm wrong about something, let me know. If you don't, you're just being a dickhead.

Yeah, watchunglava seems to have ADD. Also sorry, but he's getting it. Slowly, but that's fine.
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Old 09-15-2008, 09:31 PM   #58
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Quote:
Originally Posted by williaty View Post
This thread makes me cry.

I cant see through my tears anymore, either.

But I do have something to say to Watchunglava, If you have the Master2192 map with the flat throttle currently flashed to your ECU, i did notice that he made the throttle maps (accel pedal and throttle plate angle) "straight". I think going back to the stock map might be a bit better for driveability around town and give you somewhere to start changing the table from. I did copy the throttle maps from his flat throttle rom and tried them myself.. seemed a little tricky to start from a stop without either revving it up or bogging iot down. Im still looking into what changes are necessary. Have to go re-ead williatys DBW posts again when i have time to mess with my car for a few hours.
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Old 09-15-2008, 10:30 PM   #59
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Quote:
Originally Posted by sniper1rfa View Post
Am I wrong? Did I **** something up?
No, you're fine, that comment wasn't directed at you. You actually did a decent job of trying to get watchung on the clue train.
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Old 09-16-2008, 03:40 AM   #60
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Quote:
Originally Posted by williaty View Post
... with a sandpaper condom
Are we talking 1200 grit or like, 30?
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Old 09-17-2008, 12:53 AM   #61
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you taking your girly gab all around huh? man we gots issues! you like to talk alot , keep talkin.
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Old 09-17-2008, 12:58 AM   #62
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Originally Posted by RaceFaceXC View Post
I cant see through my tears anymore, either.

But I do have something to say to Watchunglava, If you have the Master2192 map with the flat throttle currently flashed to your ECU, i did notice that he made the throttle maps (accel pedal and throttle plate angle) "straight". I think going back to the stock map might be a bit better for driveability around town and give you somewhere to start changing the table from. I did copy the throttle maps from his flat throttle rom and tried them myself.. seemed a little tricky to start from a stop without either revving it up or bogging iot down. Im still looking into what changes are necessary. Have to go re-ead williatys DBW posts again when i have time to mess with my car for a few hours.
masters map is seriously awesome! whatever its better than what im riding around stock on.

im never gonna get anywhere tuning cause every discussion i try to have this wility mutha likes to interup with his girly talk. 05 wagon like hes a soccer mom or somethin. wheres my dinner wility!!!!!!!

the pedal takes some getting used to , no doubt. but i got the feel of it and i like it. just not right above idle. but apparantly thats baked into the cake .

whatever im allmost ase certified , so when i open my shop i guess ill pay someone to tune the ecu's
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Old 09-17-2008, 01:43 AM   #63
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Hey, wagons kick serious ass.
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Old 09-17-2008, 10:11 AM   #64
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wow this went downhill quickly...this was a good thread too. I am using his throttle changes on my car and love them, still having problems with reflashing and the car stalling out but that doesn't seem to be a problem with these edits but maybe some vac leak ::shrugs:: please keep this on-topic and contribute...i'd hate to see this crap continue
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Old 09-17-2008, 12:20 PM   #65
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Quote:
Originally Posted by watchunglava View Post
you taking your girly gab all around huh? man we gots issues! you like to talk alot , keep talkin.
am i too late to watch the internet argument? internet muscles ftl

Anyway...it's a damn shame that this dbw thing really doesnt have much of a solution...you would think after enough complaints subaru would come up with a reflash or something
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Old 09-17-2008, 12:30 PM   #66
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Originally Posted by zavier View Post
still having problems with reflashing and the car stalling out but that doesn't seem to be a problem with these edits but maybe some vac leak
Once the car has been a while after an ECU reset, use the Learning View program to look at your AF Learning. If they're larger than about 5%, there's your problem.

Otherwise, take some logs and ask the guys on the RomRaider forum.
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Old 09-17-2008, 09:17 PM   #67
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Flashed this fix onto my ecu this evening. After stalling backing out of the driveway I rather enjoyed the smoother pedal travel. Thanks for all the great work.
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Old 09-17-2008, 09:53 PM   #68
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No problem. I'm glad you got some benefit from it. I figure 90% of the work is figuring this stuff out for myself. It's not really much additional trouble to pass it on to yall.
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Old 11-03-2008, 06:24 PM   #69
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Just a few questions:
1. Does the software use linear interpolation to calculate the Target Throttle Plate Opening Angle?
i.e. 50% Accelerator Pedal Angle @ 4000RPM = 38% Target Throttle Plate Opening Angle (for the original map / look up table)?

2. If I increased the precision in the x axis and removed some of the pad (excess 100% values), would this have any effect on the way the calculations are performed. Is the lookup table a constant 2D array size, or is the memory dynamically allocated?

3. Are different tables called under different conditions? i.e. one map is for the cruise control, one map for limp mode, etc...
Or are the different maps used to help the ECU "learn" the driver's habits? i.e. If the driver is aggressive, use map 1 else if driver is sedate, use map 2, etc...

(I skimmed through things after the original post, so I apologize if these have been answered already)

Last edited by x86ect; 11-03-2008 at 06:43 PM.
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Old 11-03-2008, 06:45 PM   #70
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x86ect - I did increase the precision or resolution of the x axis like you ask about. it should only smooth out the curve of the throttle plate pos/accel pedal position graph (i.e. more points along the curve, not a straighter curve) i didnt notice any difference when using similar values, one with the extra table columns re assigned values other than 100%, and when keeping the # of useful columns the same as stock. but it makes me feel better. I dont know the answer about the memory being a constant size for that table or if its dynamic. i think if anything, its constant, but much of it is being used (wasted) for those extra 100% columns. that would seem like the most simple way. I bet TeaCups or Merchgod, over in the RR forum, would have a definite answer.
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Old 11-03-2008, 07:20 PM   #71
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Quote:
Originally Posted by x86ect View Post
Just a few questions:
1. Does the software use linear interpolation to calculate the Target Throttle Plate Opening Angle?
Didn't check your math, but yes, in interpolates when it's between values. If you do a log overlay, you'll see that the ECU is actually polling 4 cells 99% of the time.

Quote:
2. If I increased the precision in the x axis and removed some of the pad (excess 100% values), would this have any effect on the way the calculations are performed. Is the lookup table a constant 2D array size, or is the memory dynamically allocated?
You need to PM tea cups about that as that's a technical question that only he has a 100% answer to. However, the math wouldn't be any different. The ECU will still look to see which values it falls between and interpolate the resulting value. The advantage to using more columns would be getting greater resolution in an area where you didn't want a linear function.

Quote:
3. Are different tables called under different conditions? i.e. one map is for the cruise control, one map for limp mode, etc...
As far as has ever been made public, this has never been explored.
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Old 11-04-2008, 09:16 AM   #72
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Thanks, RaceFaceXC and Williaty. I'll start poking around the RomRaider forums and see if I can learn some more.

I figured out one negative to adding more precision to the table, but I think the results would be imperceptable.
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Old 11-04-2008, 12:07 PM   #73
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Quote:
Originally Posted by sniper1rfa View Post
On a throttle-cable system, your gas pedal goes right to the throttle plate. half throw on the gas pedal is half throw on the throttle plate. It may not be perfectly liner if the cam the wire rests on is not a constant radius, but it's probably close. This results in the power to the wheels NOT following the gas pedal nicely. There will be lots of change in the first half of the throw, and not a whole lot after.
I had a 2003 N/A Legacy that was not DBW, and it felt exactly as you describe with the later-model DBW systems. In other words, idle was rock solid at 700 RPM, then giving the car slight throttle made it lurch forward. Backing off slightly brought the car instantly down to idle, causing a lurch in the other direction. This was so uncomfortable for me that I sold the car with 20,000 miles on it. At the time, I asked about tweaks and adjustments, but most people said they didn't have the problem; others said it was DBW related.

Well, it wasn't DBW related in my car and it was freakin' annoying. I really liked the car otherwise but it was just so uncomfortable trying to hold the car at a steady speed. My 2003 also reacted the way you describe with cruise control. All this makes me think the "lurching" problem is not specific to DBW. There's something else going on -- too bad it won't help me with my now-sold 2003.

--Bob
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Old 11-04-2008, 01:45 PM   #74
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No, it's the same problem. With a cable-throttle, you control the "mapping" of the pedal to plate via the curve on the cam the cable attaches to. In later-model cable-throttle cars, the cam was milled with a changing radius to "pop" the throttle open off the line. To fix the problem, you get a machinist to cut you a cam with a constant radius.
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Old 11-12-2008, 01:44 PM   #75
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For the modified Requested Torque to Target Throttle Plate Opening Angle, can you save a few clock cycles by just mapping the following:

......0 100 100 100 100 100 ...
400 0 100 100 100 100 100 ...
600 0 100 100 100 100 100 ...
:

since the calculation is linearly interpolated anyways?
Sorry if this is a noob question.

Last edited by x86ect; 11-12-2008 at 01:46 PM. Reason: added extra "." for formating
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