Introducing Ed (Vaus here on i-Club), he can help those of you with MBCs!
10-13-2004, 08:58 PM
#17
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Originally Posted by vaus
I don't have an estimated time, because I have yet to find an 04 to do extensive testing on. Basically I have to find some parameter that will trigger the ecu to go to open loop immediately rather than after a dellay as it does with the TPS. If I find an 04 locally, I might be able to come up with something.
-- Ed
-- Ed
I'm confused about what exactly is "open loop". Does it imply positive feedback between throttle and fuel supply or something?
Cause then it sounds like you just need to intercept the fuel injectors/pump signal. I remember from projectwrx that the pinouts for the fuel injectors were waveforms. You could probably use an AD654 (i think that's the voltage - frequency converter) and emulate the fuel waveform.
But then i don't really know what open loop really is so I'm just talking out of my *** right now
10-13-2004, 11:19 PM
#19
Originally Posted by verc
I'm confused about what exactly is "open loop". Does it imply positive feedback between throttle and fuel supply or something?
Cause then it sounds like you just need to intercept the fuel injectors/pump signal. I remember from projectwrx that the pinouts for the fuel injectors were waveforms. You could probably use an AD654 (i think that's the voltage - frequency converter) and emulate the fuel waveform.
But then i don't really know what open loop really is so I'm just talking out of my *** right now
Cause then it sounds like you just need to intercept the fuel injectors/pump signal. I remember from projectwrx that the pinouts for the fuel injectors were waveforms. You could probably use an AD654 (i think that's the voltage - frequency converter) and emulate the fuel waveform.
But then i don't really know what open loop really is so I'm just talking out of my *** right now
The ECU has two different fueling modes... open loop and closed loop. Closed loop fueling means that the ECU is monitoring the O2 sensor to maintain a stoichometric (14.7:1) a/f ratio. Open loop fueling means that the ECU is no longer looking at the O2 sensor and instead just looking up the fueling from a table using RPM and load. When in open loop, the ECU is generally running a much richer a/f ratio than stoich (generally around 10:1).
Now that we got that settled... the ecu uses closed loop fueling while at part throttle and low boost conditions and switches to open loop under full load. The 02/03 ECU's switch to open loop at around 70% TPS and use TPS as the main trigger for the switchover. And 04 and probably 05 ecu has a 2-3 second delay between when you go WOT and it switches to open loop. It also doesn't seem to use the TPS as the main trigger anymore. This is why the OLM won't directly work on an 04.
Few... I hope that makes sense to someone
.-- Ed
10-13-2004, 11:20 PM
#20
Originally Posted by zumnwrx
vaus and verc alway confuse me.... both techy and both confusing
hehe
edgar,
hehe
edgar,
-- Ed
10-14-2004, 10:14 AM
#21
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o ic. So I suppose you could implment some preprogrammed, or userdefined lookup table for fueling as well... but then you'd be pretty much be making half of a UTEC lol. Yeah go for it!
Anyhow Ed, seeing that the newer UTEC firmware has no throttle/time delays in switching to piggyback mode, and the fact that there is an STI UTEC, I'm sure TurboXS muist have olved the problem you're having. Again I'm talking out of my *** cause I don't have the foggiest idea how a UTEC works, but TXS must have either found a another trigger within the ECU, or implemented a signal generator to manage for the fuel components.
Why would there be a 2-3 second delay before lowering the A/F? That doesn't make sense, cause what if I just floor it at 5k in 2nd on the stock turbo, I'm sure i'd reach full boost under that time frame.
Anyhow Ed, seeing that the newer UTEC firmware has no throttle/time delays in switching to piggyback mode, and the fact that there is an STI UTEC, I'm sure TurboXS muist have olved the problem you're having. Again I'm talking out of my *** cause I don't have the foggiest idea how a UTEC works, but TXS must have either found a another trigger within the ECU, or implemented a signal generator to manage for the fuel components.
Why would there be a 2-3 second delay before lowering the A/F? That doesn't make sense, cause what if I just floor it at 5k in 2nd on the stock turbo, I'm sure i'd reach full boost under that time frame.
10-14-2004, 12:09 PM
#22
Verc,
The new version of the UTEC takes over fueling completely. Supposedly it no longer piggy backs the MAF and the stock ECU's fueling tables. So when the UTEC decides to kick in, it just overrides what the ECU is trying to do and instead just runs off its own fuel table. I'm not about to start building a semi-standalone fuel computer from this little project, so I'm going to have to look at other possible solutions.
I agree that the 2-3 second dellay is ridiculous, but Subaru did it for fuel economy and emitions, deffinately not for performance. I didn't mention this, but the other prominant trigger for the switchover is RPM. I believe an 04 ECU switches to open loop past 4700RPM at pretty much any throttle position and doesn't have a dellay in doing so. I can't, however, just spoof the RPM signal to force the ECU into open loop because that would really mess with fueling and timing as well. My plan is to look at other possible triggers, namely EGT, coolant, etc to see if any of them are apropriate for this.
And FYI, on an 04 if you floor it at say 3k RPM, you will hit full boost and sustain it for several seconds before the ECU switches to open loop... scary isn't it?
-- Ed
The new version of the UTEC takes over fueling completely. Supposedly it no longer piggy backs the MAF and the stock ECU's fueling tables. So when the UTEC decides to kick in, it just overrides what the ECU is trying to do and instead just runs off its own fuel table. I'm not about to start building a semi-standalone fuel computer from this little project, so I'm going to have to look at other possible solutions.
I agree that the 2-3 second dellay is ridiculous, but Subaru did it for fuel economy and emitions, deffinately not for performance. I didn't mention this, but the other prominant trigger for the switchover is RPM. I believe an 04 ECU switches to open loop past 4700RPM at pretty much any throttle position and doesn't have a dellay in doing so. I can't, however, just spoof the RPM signal to force the ECU into open loop because that would really mess with fueling and timing as well. My plan is to look at other possible triggers, namely EGT, coolant, etc to see if any of them are apropriate for this.
And FYI, on an 04 if you floor it at say 3k RPM, you will hit full boost and sustain it for several seconds before the ECU switches to open loop... scary isn't it?
-- Ed
10-14-2004, 07:29 PM
#23
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Originally Posted by vaus
And FYI, on an 04 if you floor it at say 3k RPM, you will hit full boost and sustain it for several seconds before the ECU switches to open loop... scary isn't it?
This is exactly what I was thinking. Let's not say you are at 3k rpm, but instead travling at 40mph in top gear, and downshift to 2nd and floor it WITH a boost controller. Well, I'm glad I've got an '03 w/ ECUtek.
Anyhow, how did your microcontrolled VFD-HUD-thingmajiggy go? I did some fiddling with the A/D conversion to read ECU signals that are waveforms, but abandoned my own project cause I got lazy; my main motivation was that I was originally planning on taking an embedded systems class this quarter so I could have used it as the final project... then I started playing DOOM3.
Last edited by verc; 10-14-2004 at 07:32 PM.
10-15-2004, 01:48 AM
#24
Originally Posted by verc
This is exactly what I was thinking. Let's not say you are at 3k rpm, but instead travling at 40mph in top gear, and downshift to 2nd and floor it WITH a boost controller. Well, I'm glad I've got an '03 w/ ECUtek.
Anyhow, how did your microcontrolled VFD-HUD-thingmajiggy go? I did some fiddling with the A/D conversion to read ECU signals that are waveforms, but abandoned my own project cause I got lazy; my main motivation was that I was originally planning on taking an embedded systems class this quarter so I could have used it as the final project... then I started playing DOOM3.
Anyhow, how did your microcontrolled VFD-HUD-thingmajiggy go? I did some fiddling with the A/D conversion to read ECU signals that are waveforms, but abandoned my own project cause I got lazy; my main motivation was that I was originally planning on taking an embedded systems class this quarter so I could have used it as the final project... then I started playing DOOM3.
I never really moved ahead on the VFD display... so much other stuff to do.
-- Ed
10-18-2004, 12:47 PM
#25
Hey guys,
Someone finally took the initiative to write up a review of the OLM... here it is:
http://forums.nasioc.com/forums/show...=1#post7843376
Thanks
-- Ed
Someone finally took the initiative to write up a review of the OLM... here it is:
http://forums.nasioc.com/forums/show...=1#post7843376
Thanks
-- Ed
10-19-2004, 06:02 PM
#26
There's an update to the review now that he installed an MBC along with the OLM... for those of you too lazy to click, here's the quote 
Originally Posted by imprez25
Second Drive update:
Installed my MBC last night once I got home from work. I was able to solve all my issues with the installation of the MBC. All operator errors, ha ha.
Once I was finished with the install I took the car for a ride to set the boost levels. Set it at 16 psi in 5th gear. My desire is to have a quick car, not the fastest, nore the most expensive car just a car that will be reliable. So far between the OLM, MBC, Up pipe, and Down pipe I think I have done just that.
With the MBC boost comes up quick and the OLM does it's thing without ever letting you know. There is no sign that the device is working, only if you look at your boost gauge you can see the boost rise after 7psi. There is no hesitation, no stumbling no problems at all. EGT's are normal and not going up. Power is strong throughout the entire rpm range. Hitting boost is now like hitting a rocket tied to the top of the car. I feel the OLM allows the car to have more power down low. This helps with normal in traffic driving. Without the boost controller the car responded like that, more power in the low end, same power on the upper end. Now with the boost controller, the power just pulls you to redline. It feels great!
Big props go to Ed Vaus for coming up with this device. Allowing us 02-03 owners to seemleslly switch between open and closed loop, thus eliminating the PTFB issues caused by a MBC. This device will allow us price conscience people an opportunity to dial in our cars with out spending big bucks to do so. You go ED!
Engine mods and Costs:
Oakos MBC-$38.00
Vaus's OLM- $137.00
ERZ uppipe/downpipe- $210.00
Total costs- $385.00
Smile on my face- Priceless!
Installed my MBC last night once I got home from work. I was able to solve all my issues with the installation of the MBC. All operator errors, ha ha.
Once I was finished with the install I took the car for a ride to set the boost levels. Set it at 16 psi in 5th gear. My desire is to have a quick car, not the fastest, nore the most expensive car just a car that will be reliable. So far between the OLM, MBC, Up pipe, and Down pipe I think I have done just that.
With the MBC boost comes up quick and the OLM does it's thing without ever letting you know. There is no sign that the device is working, only if you look at your boost gauge you can see the boost rise after 7psi. There is no hesitation, no stumbling no problems at all. EGT's are normal and not going up. Power is strong throughout the entire rpm range. Hitting boost is now like hitting a rocket tied to the top of the car. I feel the OLM allows the car to have more power down low. This helps with normal in traffic driving. Without the boost controller the car responded like that, more power in the low end, same power on the upper end. Now with the boost controller, the power just pulls you to redline. It feels great!
Big props go to Ed Vaus for coming up with this device. Allowing us 02-03 owners to seemleslly switch between open and closed loop, thus eliminating the PTFB issues caused by a MBC. This device will allow us price conscience people an opportunity to dial in our cars with out spending big bucks to do so. You go ED!
Engine mods and Costs:
Oakos MBC-$38.00
Vaus's OLM- $137.00
ERZ uppipe/downpipe- $210.00
Total costs- $385.00
Smile on my face- Priceless!
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