tuners change throttle response?

[WytHorse]

Could someone please technically explain to me how it is that getting a tune modifies the throttle response time? Is this like other control systems where modifying parameters will improve response time of the system?

Driving my '12 with the factory code on it can be quite frustrating as the throttle position and the engine response don't seem to correlate well. Yes, I understand that is in part due to motor design (ie better flow all around would improve this) but I am saying even the way that the throttle seems to ramp up in steps if you just floor it vs a more linear transition.....

 

[5lho]

It ain't better flow all around would improve this, you're thinking wheezebag E7TE think here. The reason is twofold. This is a high rpm engine with correspondingly big ports and high airflow, kinda 351C 4V style. It's no truck engine first, Mustang engine second as in past iterations of this car.

Secondly, the throttle logic is trying to maximise fuel economy and lower emissions through precise throttle control. This is happening live, takes a touch of time and lends that disconnected feel to the E-throttle. Almost every E-throttle car I've tried has some of this on stock calibration.

A tune, sharpens this logic up and dispenses with the OEM concerns around fuel economy and emissions in favour of performance.

 

[NickSezz]

^^

There's more too it but I can't articulate that as well as someone else.

But to answer your question, yes, a good tuner will make this issue almost disappear. This is the exact reason I am switching tuners right now. My current tune is better than stock, but still has that disconnected feel and that's the whole reason I wanted a tune!

 

[stang8psi]

I believe they change the signal voltage to open the throttle sooner and faster.

 

[NickSezz]

A good tune will also change what and how the torque, fuel, spark tables are selected and how those tables are written. Something like that...

 

[Full_Tilt]

Google "Torque management", that pretty much explains it, when you think how it would be used for economy.

I miss my throttle cable...

 

[SoCal81]

+1 for throttle cables.

 

[WytHorse]

well, what are some things to look for that would indicate that one tune is better than another. lol and yes I'm sure the cost is a good indication...but what kind of questions should I ask or what things should I look for?

 

[5lho]

For sharp response, nothing beats the Procal tune from FRPP. there's a big torque bump right off the bottom and it transforms the car in running around situations, particularly if you have 3:31s and the stick.

I hear Steeda's got this part worked out pretty well too, if you're ok with complete aftermarket.

The balance is, you can either go for max peak gains or reduce those and get the killer daily driveability we're talking about here. Tough to get both but, not hard to get a good balance of each if that works for you.

I have the Procal, the FRPP warranty and the killer driveability that comes with it. I haven't had any issues with this tune. Were I to go straight into the more obvious aftermarket and buy a canned tune, I'd probably hit up Steeda or Shaun at AED.

 

[WytHorse]

^ That is exactly what my next question was going to be. I assumed it was a trade off of "daily driveablilty" vs pushing for peak gains. In my mind I am not very fond of pushing the motor for the last 5 hp for bragging rights...this is my daily and I need it to last me a long time...

 

[Sky Render]

I believe they change the signal voltage to open the throttle sooner and faster.

The throttle motor is a stepper motor. You cannot increase the voltage.

The throttle response is most likely increased by changing the parameters of the software PID controller that handles the throttle plate position and removing parameters specific to emissions and fuel economy. (Not that fuel economy or emissions would necessarily increase.)

 

[WytHorse]

The throttle motor is a stepper motor. You cannot increase the voltage.

The throttle response is most likely increased by changing the parameters of the software PID controller that handles the throttle plate position and removing parameters specific to emissions and fuel economy. (Not that fuel economy or emissions would necessarily increase.)

ahh I was wondering if it was PID control...nice, now I can totally relate to what you are saying

 

[Sky Render]

ahh I was wondering if it was PID control...nice, now I can totally relate to what you are saying

I'm just assuming it's a software-based PID controller. That's how i'd build it, at least.

Sent from my toilet using Tapatalk.

 

[WytHorse]

I'm just assuming it's a software-based PID controller.

ok, thanks for clarifying that...

 

[dontlifttoshift]

I like the way it opens the throttle stock....is there a way to make it close faster? I like engine braking when I let off the gas.

 

[Full_Tilt]

I like the way it opens the throttle stock....is there a way to make it close faster? I like engine braking when I let off the gas.

Ive noticed that too, it feels like when you let off soddenly it keeps the throttle cracked like youre cruising for a second. I guess the reason is for economy because idiot drivers that have poor throttle control.

 

[NickSezz]

I think that has something to do with coasting fuel shut off? My 05 V6 had almost no engine braking with my supercharger tune and Lund couldn't even figure out why in a reasonable amount of time so I just lived with it. My rpms going down looked like a clock ticking backwards...My 5.0 is much better with this, stock and tuned.

I think the slow reaction the stock tune has is for driver control reasons and is probably easier on drive-train parts over time.

 

[Sky Render]

I like the way it opens the throttle stock....is there a way to make it close faster? I like engine braking when I let off the gas.

I wonder if this is due to throttle control or if it is the PCM taking a brief amount of time to cut the fuel. Like if it has to switch cam profiles or something first.

 

[2013kAB]

hi, first post referred here by soundguydave. i would like to hear more about this, the engine braking. it's one of the first things i noticed in my '13 5.0. i read an online article i can't find anymore but it said on the boss 302 it modified parameters including engine braking. sometimes it almost feels like braking and engine are fighting each other for a bit.
steve

 

[BruceH]

It ain't better flow all around would improve this, you're thinking wheezebag E7TE think here. The reason is twofold. This is a high rpm engine with correspondingly big ports and high airflow, kinda 351C 4V style. It's no truck engine first, Mustang engine second as in past iterations of this car.

Secondly, the throttle logic is trying to maximise fuel economy and lower emissions through precise throttle control. This is happening live, takes a touch of time and lends that disconnected feel to the E-throttle. Almost every E-throttle car I've tried has some of this on stock calibration.

A tune, sharpens this logic up and dispenses with the OEM concerns around fuel economy and emissions in favour of performance.

Not even close.

A good tune will also change what and how the torque, fuel, spark tables are selected and how those tables are written. Something like that...

Kind of.

Ive noticed that too, it feels like when you let off soddenly it keeps the throttle cracked like youre cruising for a second. I guess the reason is for economy because idiot drivers that have poor throttle control.

I thought you were a tuner? At least you have claimed to tune vehicles before.

I wonder if this is due to throttle control or if it is the PCM taking a brief amount of time to cut the fuel. Like if it has to switch cam profiles or something first.

No.

It's fairly simple. Depressing the throttle correlates to a parameter called pedal position or pp. There is a table in the tune that commands torque by pedal position. The stock tune is set up for predictability and driveability. For the sake of this discussion lets say that a pp of 100 = 100 tq. The ecu looks up what parameters will produce 100 torque and applies them. Now, lets say tuner 1 commands 300 tq at 100 pp. You don't have any more engine power but since more power is commanded for the same pp it feels like the car is super powerful. Someone drives a car with the tuner 1 tune and thinks it must be the tuners skill that is providing all the extra power. The truth is it's just trickery. There is no direct link between the pedal and tb like with a cable. Using drive by wire allows for far better driveability and linear power delivery imo. I have mine adjusted exactly like I want it.

Why do the rpms hang? This is all tune. There is a delicate balance between surging, hanging rpm, and stalling. The main parameters used to control this are dashpot and isc. Basically they adjust how much air is allowed in to compensate for the cam profile, engine volume, rpm, and throttle body.

These are just a few of the things that allow us to have 600rwhp+, good fuel economy, and excellent driveability. Things like this weren't possible 30 years ago when motors had carburators, points, condenser, and rotor.

We are in the best of times for musclecars and computer control makes it possible.

Edit: Here's a screen shot of my drive by wire table. You can see that I'm commanding a certain torque in newton meters at corresponding pp and rpm. I realize that a lot of this stuff is hard to visualize. Keep in mind that at wot the torque table is ignored. There are a lot more tables that the ecu uses to determine the torque used in this table.

Hopefully this helps.