B4_Maniac Posted June 7, 2004 Share Posted June 7, 2004 Why doesn't the 05 Legacy come with drive by wire?? Link to comment Share on other sites More sharing options...
Dr. Zevil Posted June 7, 2004 Share Posted June 7, 2004 I thought it did. I know the STi does.. where do you get your info? Link to comment Share on other sites More sharing options...
B4_Maniac Posted June 7, 2004 Author Share Posted June 7, 2004 [quote name='Dr. Zevil']I thought it did. I know the STi does.. where do you get your info?[/quote] Copy and paste this into your browser. http://vocuspr.vocus.com/VocusPR30/Temp/{c0db4dd1-53da-4fa0-8807-3375f603b9d1}/2005%20Legacy%202.5%20GT%20Specs.pdf It uses some called Electronic Throttle Control..but its not drive by wire..mabey similar..but I couldn't find a explanation to figure out the diffrence.... I was suprised that is doesn't. But reading the spec sheet and compareing it with the STI, the Legacy has some new tech that the STI doesn't. The intercooler on the new LEG is a piece of work...dont' be suprised if the new STI uses a similar config.. But, the Legacy...belive it or not should handle better than the STI!! It is the only one in the line up with a rear multilink suspension.... :o Link to comment Share on other sites More sharing options...
B4_Maniac Posted June 7, 2004 Author Share Posted June 7, 2004 [url]http://www.infineon.com/cmc_upload/0/000/012/459/SE_0899_electronic_throttle_control.pdf[/url] Link to comment Share on other sites More sharing options...
B4_Maniac Posted June 7, 2004 Author Share Posted June 7, 2004 I now now the diffrence... Drive by Wire is completely electronic and the ETC is jus reducing the number of steps between the throttle and the ECM (mechanicly that is) [url]http://www.edmunds.com/news/innovations/articles/43033/article.html[/url] Wow.. Link to comment Share on other sites More sharing options...
SUBE555 Posted June 7, 2004 Share Posted June 7, 2004 The STi and Legacy GT both note the exact same system. I didn't have time to read the whole tech doc you mentioned, but from what I understand with the Subaru system, there is little difference between ETC and DBW other than naming rights perhaps. Is ETC a Subaru name for it? Link to comment Share on other sites More sharing options...
Control Freak Posted June 7, 2004 Share Posted June 7, 2004 Here's a little background on myself before I try to answer this. I am an Engine Control System Engineer. Therefore, I design the software for ECU's, ECM's, EMS's, etc. This explains the origins of my username by the way. Anyway, from the material I'm seen so far, the Legacy has throttle-by-wire. This means the pedal is not directly connected to a throttling valve. Instead, you are telling the ECU what throttle position you want to go to by depressing the pedal. The ECU sees this as a reference point it will target but it is free to decide how to get to that point. The decision it makes will be constrained by factors including A/F, emissions, and engine protections. Throttle-by-wire systems can also improve the performance of the car. However, they are governed by some fairly complicated equations and many people have complained of a “throttle lag” experienced with these systems. I believe these issues will be resolved in the next couple years and throttle-by-wire will become standard on almost all vehicles. Drive-by-wire is a fairly broad term and not completely universally agreed upon. The most common use for this term refers to replacing the steering with a sensor on the steering wheel and a motor(s) to move the front wheels. This has a great advantage because you can really tune a system electronically to act the way you would like. It also has a safety advantage because the metal rod in the steering column that is basically pointed at your heart can be removed. I am not aware of any production cars that use this technology. I doubt we will see any vehicles with it until the 12 volt power systems are replaced with 42 volt systems because the power requirements are so much higher for drive-by-wire. I hope this helps. Link to comment Share on other sites More sharing options...
gtguy Posted June 7, 2004 Share Posted June 7, 2004 No, that doesn't help at all, Control Freak. Thanks for nothing! :lol: :lol: I learned quite a lot from that post. Thanks loads for taking the time. One more reason this space rules. :D The Drive-by-wire explanation explains why so far, we've only seen it on Formula One (and other zooty racing series) cars. Kevin Link to comment Share on other sites More sharing options...
B4_Maniac Posted June 7, 2004 Author Share Posted June 7, 2004 [quote name='Control Freak']Here's a little background on myself before I try to answer this. I am an Engine Control System Engineer. Therefore, I design the software for ECU's, ECM's, EMS's, etc. This explains the origins of my username by the way. Anyway, from the material I'm seen so far, the Legacy has throttle-by-wire. This means the pedal is not directly connected to a throttling valve. Instead, you are telling the ECU what throttle position you want to go to by depressing the pedal. The ECU sees this as a reference point it will target but it is free to decide how to get to that point. The decision it makes will be constrained by factors including A/F, emissions, and engine protections. Throttle-by-wire systems can also improve the performance of the car. However, they are governed by some fairly complicated equations and many people have complained of a “throttle lag” experienced with these systems. I believe these issues will be resolved in the next couple years and throttle-by-wire will become standard on almost all vehicles. Drive-by-wire is a fairly broad term and not completely universally agreed upon. The most common use for this term refers to replacing the steering with a sensor on the steering wheel and a motor(s) to move the front wheels. This has a great advantage because you can really tune a system electronically to act the way you would like. It also has a safety advantage because the metal rod in the steering column that is basically pointed at your heart can be removed. I am not aware of any production cars that use this technology. I doubt we will see any vehicles with it until the 12 volt power systems are replaced with 42 volt systems because the power requirements are so much higher for drive-by-wire. I hope this helps.[/quote] Yes it does help. My RX8 has drive by wire, and I thought the Legacy would too. But, hopefuly Subaru has refined the system so it doesn't have "throttle lag"..but it is the only one in the line up to use it.. Sube555 read the docs... they are a good read. Link to comment Share on other sites More sharing options...
Drift Monkey Posted June 7, 2004 Share Posted June 7, 2004 [quote name='B4_Maniac']Yes it does help. My RX8 has drive by wire, and I thought the Legacy would too. But, hopefuly Subaru has refined the system so it doesn't have "throttle lag"..but it is the only one in the line up to use it.. Sube555 read the docs... they are a good read.[/quote] I was under the impression that the STi used throttle-by-wire as well. Good articles BTW Maniac. Link to comment Share on other sites More sharing options...
B4_Maniac Posted June 7, 2004 Author Share Posted June 7, 2004 quote] I was under the impression that the STi used throttle-by-wire as well. Good articles BTW Maniac.[/quote] Thanks! I try Monkey..I try! Link to comment Share on other sites More sharing options...
Control Freak Posted June 7, 2004 Share Posted June 7, 2004 The RX-8 is the closest thing you can get to drive by wire I know of in current production cars. They basically rapped an electric motor coil around the steering column. This replaces the hydraulic assist with an electrical assist which is much more responsive. There still are some limitations to how much you can tune the steering response because you continue to have a mechanical connection to the front wheels. I was very close to buying an RX-8. I loved the smoothness of the rotary, the low center of gravity, and the electrically assisted steering. In the end I just couldn't get away with a RWD while living in a snow-belt region of Pennsylvania. I figure the extra 12 horses in the Legacy and the AWD will more than make up for anything I'm trading off. The RX-8 is a beautiful car though and I loved my test drive. Link to comment Share on other sites More sharing options...
outahere Posted June 7, 2004 Share Posted June 7, 2004 [quote name='Control Freak'] Drive-by-wire is a fairly broad term and not completely universally agreed upon. The most common use for this term refers to replacing the steering with a sensor on the steering wheel and a motor(s) to move the front wheels. [/quote] Why is this not called "steer by wire"? Link to comment Share on other sites More sharing options...
Drift Monkey Posted June 7, 2004 Share Posted June 7, 2004 [quote name='outahere'][quote name='Control Freak'] Drive-by-wire is a fairly broad term and not completely universally agreed upon. The most common use for this term refers to replacing the steering with a sensor on the steering wheel and a motor(s) to move the front wheels. [/quote] Why is this not called "steer by wire"?[/quote] As he said, it is a broad term. Drive-by wire is generally accepted term IIRC. Link to comment Share on other sites More sharing options...
Control Freak Posted June 7, 2004 Share Posted June 7, 2004 [quote]outahere wrote: Why is this not called "steer by wire"?[/quote] I can say that naming conventions don't always make the most sense in this industry. :roll: I believe the term was simply adapted from aircraft where it is called fly-by-wire. It is a term still being developed and some throw brake-by-wire and throttle-by-wire under this name also. Link to comment Share on other sites More sharing options...
B4_Maniac Posted June 7, 2004 Author Share Posted June 7, 2004 [quote name='Control Freak']The RX-8 is the closest thing you can get to drive by wire I know of in current production cars. They basically rapped an electric motor coil around the steering column. This replaces the hydraulic assist with an electrical assist which is much more responsive. There still are some limitations to how much you can tune the steering response because you continue to have a mechanical connection to the front wheels. I was very close to buying an RX-8. I loved the smoothness of the rotary, the low center of gravity, and the electrically assisted steering. In the end I just couldn't get away with a RWD while living in a snow-belt region of Pennsylvania. I figure the extra 12 horses in the Legacy and the AWD will more than make up for anything I'm trading off. The RX-8 is a beautiful car though and I loved my test drive.[/quote] The RX8 is a great car, but I need to save some cash..and getting 13 miles to the galon and only 180 miles out of a full tank of gas gets costly.. Plus, I can't use it all year long. I will get another one mabey in 06.. Link to comment Share on other sites More sharing options...
Th3Franz Posted June 7, 2004 Share Posted June 7, 2004 Just curious, but what software do you use to write the controls for the ECUs and the like? I'm an Electrical Engineer in training, so I have been learning a little bit about control logic, etc. :D -Franz The end of a Legacy http://www.youtube.com/th3franz Link to comment Share on other sites More sharing options...
Control Freak Posted June 7, 2004 Share Posted June 7, 2004 I use Matlab with Simulink and Real Time Workshop. RTW turns the Simulink models in to C code which is then compiled and load on to the boards. It's really a pretty cool process. I can find a bug in test, turn out new software, and load it in about an hour. Link to comment Share on other sites More sharing options...
GBY Posted June 7, 2004 Share Posted June 7, 2004 Thanks for the info CF :) Link to comment Share on other sites More sharing options...
B4_Maniac Posted June 7, 2004 Author Share Posted June 7, 2004 [quote name='Control Freak']I use Matlab with Simulink and Real Time Workshop. RTW turns the Simulink models in to C code which is then compiled and load on to the boards. It's really a pretty cool process. I can find a bug in test, turn out new software, and load it in about an hour.[/quote] So can you map out the new Legs ECU to get 14.5 psi?? Link to comment Share on other sites More sharing options...
outahere Posted June 7, 2004 Share Posted June 7, 2004 [quote name='Control Freak']I use Matlab with Simulink and Real Time Workshop. RTW turns the Simulink models in to C code which is then compiled and load on to the boards. It's really a pretty cool process. I can find a bug in test, turn out new software, and load it in about an hour.[/quote] They need engineers like you over at Nissan. They cannot figure out how to combine stability control and an electric, locking rear differential on their Titan truck. Link to comment Share on other sites More sharing options...
SUBE555 Posted June 8, 2004 Share Posted June 8, 2004 [quote name='B4_Maniac'][quote name='Control Freak']I use Matlab with Simulink and Real Time Workshop. RTW turns the Simulink models in to C code which is then compiled and load on to the boards. It's really a pretty cool process. I can find a bug in test, turn out new software, and load it in about an hour.[/quote] So can you map out the new Legs ECU to get 14.5 psi??[/quote] Or you can get a tuner tuned Accessport specific to your needs. 14.5psi without changes in various portions of the ECU properties would be less efficient and effective. Link to comment Share on other sites More sharing options...
Drift Monkey Posted June 8, 2004 Share Posted June 8, 2004 [quote name='outahere']They need engineers like you over at Nissan. They cannot figure out how to combine stability control and an electric, locking rear differential on their Titan truck.[/quote] I'm curious why you say that. What kind of results does Nissan's system yield? Link to comment Share on other sites More sharing options...
Control Freak Posted June 8, 2004 Share Posted June 8, 2004 [quote name='B4_Maniac'][quote name='Control Freak']I use Matlab with Simulink and Real Time Workshop. RTW turns the Simulink models in to C code which is then compiled and load on to the boards. It's really a pretty cool process. I can find a bug in test, turn out new software, and load it in about an hour.[/quote] So can you map out the new Legs ECU to get 14.5 psi??[/quote] Well if I had the original source code yes. I'm not ambitious enough to rewrite the entire ECU software on my own. :) A lot of aftermarket places like Cobb tuning simply rewrite the maps that are in flash memory. If I had a list of the configurable memory parameters for the Legacy ECU I could do that on my own. Of course I would have to know what to put in the maps and I don't own my own dyno to do performance tuning on. So I will probably just pay Cobb for their AccessECU when it ready just so I can take advantage of their tuning experience. Other aftermarket places like ECUTek replace the entire ECU. Frankly, that scares me. This means they are writing their own ECU software not just tweaking some parameters. From my experience manufactures tend to put a lot of stuff in their software that is special for their engines. People who were not part of the original design team or have access to their design folders would not know about things like engine protection around operating regions a particular engine may not like. So for me the fact the Cobb only reprograms the map is a big advantage. Here is an excerpt from their web site. “By directly accessing the stock ECU, we can reprogram the engine management functions with improved performance in mind without sacrificing any of the robust safety and driveability features Subaru has incorporated.” Link to comment Share on other sites More sharing options...
Drift Monkey Posted June 8, 2004 Share Posted June 8, 2004 Hey control freak, how about hacking the software the "marries" the accessport to it's corresponding ECU? That way everyone can flash their cars for free? :P Link to comment Share on other sites More sharing options...
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