What’s the benefit of drive by wire?

I’m not implying I know there’s no benefit. Just asked a question. And I don’t automatically believe the positives outweigh the negatives just because mr auto manufacturer said so. Maybe…maybe not. I’m aware of several things auto manufacturers incorporated into vehicles that turned out to be a PITA.

Not questioning anything is akin to believing anything. Hence Jonestown. Yes it was a tragedy. That could have been avoided if people asked questions. I will remove the statement.

Save the manufacturer money.

As a side note, I’m beginning to understand that this is a very “proper” forum. Politically correct and such. “Please do not question the manufacturer, or mention politics, religion, unions, global warming, or The View”.

Ahhh, but you’re a cynical ole boy! Haha

Like I said above, you can have:

  1. A mechanical throttle body, an electro-mechanical Idle Air Control Valve, and an electro-mechanical cruise control system.

Or

  1. An electronic throttle body.

Option 2 is vastly simpler than option 1.

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There have been heated and ugly discussions, in regards to politics, unions and global warming, among other things

Feel free to go down that road, but eventually Carolyn will intervene

As far as “please do not question the manufacturer” . . . I really don’t know what discussion you’re referring to

Not really. I have no qualms about manufacturers advancing technology to reduce manufacturing costs. I spent over 20 years in manufacturing in engineering and management up to and including senior levels. Changing technology to reduce manufacturing costs is one of the ways we got to where we are.

Hi. We try to keep the forum in the spirit of the show, and stick to car and driving topics. We do have a lot of people here who participate without having been listeners. Having been around here for ten years now (!) I can tell you that we’ve learned the hard way that it’s much more enjoyable for everyone if we don’t have political discussions. I gently differ that this is out of political correctness. People’s views here span the spectrum. (+1 to @db4690, basically)

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In some cases, the engine’s power output may be controlled by means other than throttle opening. I believe the Prius cars reduce power by altering valve timing to a large extent, going into Atkinson mode during low power cruise and going closer to a true Otto cycle for maximum power.

I find the “lag” on some DBW systems is from sluggish transmissions rather than delayed responses. I have driven two DBW cars with excellent transmissions and one with a transmission that epitomized the old label of “slush box”. The differences in responsiveness were tremendous, and directly corresponded to the responsiveness of the transmissions.

My current Mazda 6 responds immediately and urgently to my demands for starting up and passing power. I have never noticed any lag.

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I also want to address lag time.

There are algorithms that can anticipate driver reaction, so the car would be ready to do something BEFORE the driver gives the car input.

For example: Formula 1 engines use 2 hybrid units - one on the engine output, and one on the turbo. If the turbo could be spooled up BEFORE the driver mashes the throttle = no turbo lag!

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CapriRacer is referring to Kalman filters I do believe… :smile:

Didn’t know there was even a name for them - but, YES! That is what I was referring to.

One big advantage in sporty vehicles is the ability for the drive by wire system (throttle is just part of it) to automatically blip the throttle on downshifts. It is a big help with both manual and also automatics. It makes the downshifts smoother. If you are an old-school heel and toe person, it is defeatable, so you can strip your own synchros ;). In vehicles with paddle shifters and dual clutch automatics it is a vital part of making those cars downshift smoothly and perfectly via paddles or the transmission algorithm
while cornering to eliminate torque transfer (unwanted) and then unwanted understeer or oversteer depending on the car’s drivetrain.

In addition, the DBW can precisely coordinate everything, which can improve economy and reduce emissions, instead of monitoring the ragged movements of the throttle in response to my foot. So the DBW throttle might not do exactly what my foot is doing - it’s doing it ‘better’, emissions and mpg - wise.

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It’s the “better” part that I don’t like. The car doesn’t know what I want to do. I may want to bark the tires a little and peel away when the light turns green.

Traction control won’t like that let alone the DBW. Unless, of course you drive a Mustang, Camaro or Charger. The engineers on those cars allow a bit of tire spin from a stop and have buttons that turn off Traction Control for smokin’ starts. Heck Ford has a “Burnout Mode” that holds the front brakes like an old line-lock and allows the rear tires to royally smoke the tires

Other, more dignified brands, would not approve of such frivolity! :smile:

Has anyone performed the driving technique called “donuts?” How is it done?

Yes… got thrown by your original term “donut hole”

On a slippery (wet or snow) surface, its easy in nearly any rear wheel drive car with some decent power. You want to spin (and keep spinning) the wheels from a stop, turn right (or left) and as the car swings around counter steer to opposite way as the car turns in a donut. Keep the tires spinning enough to keep the car moving in a circle. A slight bit of front brake can help, too. It takes some practice to keep in going in a uniform circle without spinning out.

On dry pavement it takes enough power to bust the tires loose i the dry and serious steering wheel work keep them spinning and driving in a circle. Do it long enough and you will get smoke from the spinning tires.

A sad version can be done with a front wheel drive car and the handbrake but its nearly impossible to keep the donut going a full 360 degrees.

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