Drive by wire question.. Please help!
#21
That is not lag. That is the ECU control strategy saying that at the current load levels, the amount of throttle you are requesting (WOT) will actually do nothing to improve performance and will be a detriment. Therefore the ECU will wait until load levels increase to the point that the requested throttle actually justifies the further opening of the throttle body.
Lag is the amount of time it takes from the moment the beginning of an event occurs to the the moment that event is detected. In this case the ECU sees the change in requested throttle, and then when conditions are met actually modifies the amount the throttle body is open.
You can change the system, for $10 in parts, to behave like a direct-cable system. But you will see no increase in power or efficiency, and will actually measure a loss.
Lag is the amount of time it takes from the moment the beginning of an event occurs to the the moment that event is detected. In this case the ECU sees the change in requested throttle, and then when conditions are met actually modifies the amount the throttle body is open.
You can change the system, for $10 in parts, to behave like a direct-cable system. But you will see no increase in power or efficiency, and will actually measure a loss.
#22
and why do you think the ecu "stratagy" is the way it is....perhaps cause its a dbw system (amongst other reasons)
why is it all the cable systems out that i have ever driven has better response than the tc. the response i am talking about is the amount of time it takes from the time i hit the gas till the engine's rpm increase...this is what most might consider lag...you can very very easily compair a dbw car and a cable car..no butt dyno involved...all dbw cars that i have heard of have this "lag" that is worse than cable cars.
perhaps this "lag" in dbw is for a good reason but some just want to get rid of it.
why is it all the cable systems out that i have ever driven has better response than the tc. the response i am talking about is the amount of time it takes from the time i hit the gas till the engine's rpm increase...this is what most might consider lag...you can very very easily compair a dbw car and a cable car..no butt dyno involved...all dbw cars that i have heard of have this "lag" that is worse than cable cars.
perhaps this "lag" in dbw is for a good reason but some just want to get rid of it.
#23
Originally Posted by Obike
That is not lag. That is the ECU control strategy saying that at the current load levels, the amount of throttle you are requesting (WOT) will actually do nothing to improve performance and will be a detriment. Therefore the ECU will wait until load levels increase to the point that the requested throttle actually justifies the further opening of the throttle body.
Lag is the amount of time it takes from the moment the beginning of an event occurs to the the moment that event is detected. In this case the ECU sees the change in requested throttle, and then when conditions are met actually modifies the amount the throttle body is open.
You can change the system, for $10 in parts, to behave like a direct-cable system. But you will see no increase in power or efficiency, and will actually measure a loss.
Lag is the amount of time it takes from the moment the beginning of an event occurs to the the moment that event is detected. In this case the ECU sees the change in requested throttle, and then when conditions are met actually modifies the amount the throttle body is open.
You can change the system, for $10 in parts, to behave like a direct-cable system. But you will see no increase in power or efficiency, and will actually measure a loss.
now if anyone has any useful info.. please chim in.. thanks!
#24
DBW lag does NOT exist.
any real tuner? wat about asking mechanical engineers or real mechanics or whatnot.
if i recall correctly, obike has more experiance in this stuff than all of us combined.
the moment from the signal of the throttle to the actual command of the throttle movement is less than a millisecond. seriously.
are you guys electrical majors or anything?
any real tuner? wat about asking mechanical engineers or real mechanics or whatnot.
if i recall correctly, obike has more experiance in this stuff than all of us combined.
the moment from the signal of the throttle to the actual command of the throttle movement is less than a millisecond. seriously.
are you guys electrical majors or anything?
#25
Originally Posted by stevejohns29
now if anyone has any useful info.. please chim in.. thanks!
#26
Originally Posted by aen
DBW lag does NOT exist.
any real tuner? wat about asking mechanical engineers or real mechanics or whatnot.
if i recall correctly, obike has more experiance in this stuff than all of us combined.
the moment from the signal of the throttle to the actual command of the throttle movement is less than a millisecond. seriously.
are you guys electrical majors or anything?
any real tuner? wat about asking mechanical engineers or real mechanics or whatnot.
if i recall correctly, obike has more experiance in this stuff than all of us combined.
the moment from the signal of the throttle to the actual command of the throttle movement is less than a millisecond. seriously.
are you guys electrical majors or anything?
im just looking at it through compairison....the time it takes a cable system to respond compaired to dbw....all im saying is that from my experiance ther IS a difference between the two. Im not saying Obike is wrong but perhaps we are looking at it through different eyes so to speak.
#28
Originally Posted by Obike
Originally Posted by stevejohns29
now if anyone has any useful info.. please chim in.. thanks!
what i was saying about the tuner was.. call Paul from Dezod. He has seen and dealt with the drive-by-wire lag and is the one who told me that it was my problem. I was just double checking to see what other people thought. Also Rob from Descendent has dealt with this problems (considering they even make a controller for it) I was looking for feedback on if anyone has used these controllers or have had similar problems to mine.
#30
Originally Posted by crush02342002
I dont think it "bypasses" the ecu but does something to the signal (or voltage if you will). Rob from decendant posted a sorta scematic of it.
#32
ima call a couple tuners tomorrow. and my one friend whose and electircal engeenier ( has a subie making 600 whp) to see if they can shed any light .. ill post an update tomorrow.
#33
would an aem ems a cure for this ? I went to race wars this weekend and there was a few evo's and stis that were running those controllers. why do they have so many controllers for dbw lag if it is not part of the dbw system ? there is not one car that is dbw that has as fast as response as a cable car.
#34
#35
Originally Posted by scikotictc232
would an aem ems a cure for this ? I went to race wars this weekend and there was a few evo's and stis that were running those controllers. why do they have so many controllers for dbw lag if it is not part of the dbw system ? there is not one car that is dbw that has as fast as response as a cable car.
#36
looks like blitz also makes one.. it shows a graph showing how it opens the throttle ..
http://www.jscspeed.com/universal/el...controller.htm
http://www.jscspeed.com/universal/el...controller.htm
#38
Originally Posted by stevejohns29
Originally Posted by Obike
Originally Posted by stevejohns29
now if anyone has any useful info.. please chim in.. thanks!
So, here's the solution. Recirculate the BOV, switch to a DV/BPV, place the MAF after the BOV, or go with a stand-alone ECU that is map-based (Hydra, AEM, Bosch, Motech, etc). The sensor you tune off of means nothing in this case, as a piggyback is only altering data from the primary ECU. So when the primary ECU freaks out and tries to correct something, the piggyback is only along for the ride and only can do so much. There are ways you can TRY to fix it, but they are band-aids. The solution is what I've posted.
Get the recirculation fitting, get a weld-on 1" NPT fitting, then get a 1" hose-barb to NPT adapter. You will then use 1" silicone hose back to the intake AFTER the MAF. Voila, problem solved.
Again... nothing to do with DBW here.
#39
Originally Posted by Obike
Originally Posted by stevejohns29
Originally Posted by Obike
Originally Posted by stevejohns29
now if anyone has any useful info.. please chim in.. thanks!
So, here's the solution. Recirculate the BOV, switch to a DV/BPV, place the MAF after the BOV, or go with a stand-alone ECU that is map-based (Hydra, AEM, Bosch, Motech, etc). The sensor you tune off of means nothing in this case, as a piggyback is only altering data from the primary ECU. So when the primary ECU freaks out and tries to correct something, the piggyback is only along for the ride and only can do so much. There are ways you can TRY to fix it, but they are band-aids. The solution is what I've posted.
Get the recirculation fitting, get a weld-on 1" NPT fitting, then get a 1" hose-barb to NPT adapter. You will then use 1" silicone hose back to the intake AFTER the MAF. Voila, problem solved.
Again... nothing to do with DBW here.
instead of doing all of that.. if i just would go with a WOT box, wouldn that fixmy problem? Considering your blow off wont fire if you never lose boost?