Throttle Lag on JB4 on Stinger GT

[Leslie Lim]

Hello

I have the JB4 on my Stinger GT RWD. Running the default Map 01.
With BMS Air Intake, but no fuel wires. 93 Octane.

1) After installation, I felt a certain throttle lag, before the very satisfying pull...reminded me of my Subaru with big turbo lag.
=> The lag happens in every gear.
=> There is no traction issues (no traction control lights).

2) Yesterday, I sent the car in for servicing with the dealer. So I removed the JB4.
=> the throttle response suddenly became noticeably sharper.
=> Of course, the pull is not as strong when the turbo spools up.

3) Sent the log to Terry before with JB4. He told me to cut the boost in 1st and 2nd gear.
=> it didn't make difference.
=> again, I didn't expect any improvement, since there was no traction issues to begin with.

Wonder if anyone else have this throttle lag observations?
Otherwise, I am loving the JB4! The installation is way idiot proof. And the pull is amazing.

 

[Terry@BMS]

There isn't a negative impact to throttle response with any of the JB4 maps, but if you want to remap it more directly try the pedal tuner: BMS Pedal Tuner

 

[StungBlueGT2]

Hello

I have the JB4 on my Stinger GT RWD. Running the default Map 01.
With BMS Air Intake, but no fuel wires. 93 Octane.

1) After installation, I felt a certain throttle lag, before the very satisfying pull...reminded me of my Subaru with big turbo lag.
=> The lag happens in every gear.
=> There is no traction issues (no traction control lights).

2) Yesterday, I sent the car in for servicing with the dealer. So I removed the JB4.
=> the throttle response suddenly became noticeably sharper.
=> Of course, the pull is not as strong when the turbo spools up.

3) Sent the log to Terry before with JB4. He told me to cut the boost in 1st and 2nd gear.
=> it didn't make difference.
=> again, I didn't expect any improvement, since there was no traction issues to begin with.

Wonder if anyone else have this throttle lag observations?
Otherwise, I am loving the JB4! The installation is way idiot proof. And the pull is amazing.

Unfortunately, Ive heard this from a few people and felt it in my buddies JB4 Stinger. However, I noticed a similar effect from just adding Intakes. So we believe they both cause minimal lag and the combination of both mods makes it more noticeable.

Ill try to clarify the feeling or effect from each mod. The throttle lag from the JB4 is very minimal and feels more like restrictions in the speed of CPU data processing. Another words, the lag feels like a spit second delay while the JB4 CPU re-formats the ECU data to alter the engine parameters. I know the JB4 processor is very fast, but even the fastest computer/phone still lags slightly when processing alot of information. Switching to Map0 mostly eliminates that feeling and removing the JB4 completely allows quickest response to throttle inputs. Again, this is very minimal and dont think most users ever notice a difference.

Now the intakes themselves cause a different type of lag, and believe its caused by a combination of factors since the degree of the effect varies. I first noticed this feeling before I added heat shields which makes me believe its partially caused by hot engine air being drawn into the intakes. It was less noticeable over 30mph, and is now almost nonexistent after installing a wall of heat shielding.

The other factor is the loss of the stock airbox. I have a theory why this may effect throttle input. Less restriction typically means more high RPM HP, but less low RPM torque. That would mean throttle "tip-in" may feel delayed or softer until boost/power builds. I still notice this occasionally and sometimes its worse than others. Putting the stock airbox back on gives back the quick throttle response, but significantly reduces the top end pull over 4k.

If you removed both the intakes & JB4 for service that may be why you actually noticed the change in throttle input. If you havent already, maybe try stock intakes with the JB4 and see if you feel the same differences.

I hope this helps, keep the feedback coming, and good to know its just not in our heads. Lol

 

[Pnbnationsbest]

All of ^ right there is why we desperately need flash tuning!

 

[Leslie Lim]

All of ^ right there is why we desperately need flash tuning!

Flashing is troublesome when u want to revert back.

 

[Terry@BMS]

Ill try to clarify the feeling or effect from each mod. The throttle lag from the JB4 is very minimal and feels more like restrictions in the speed of CPU data processing. Another words, the lag feels like a spit second delay while the JB4 CPU re-formats the ECU data to alter the engine parameters. I know the JB4 processor is very fast, but even the fastest computer/phone still lags slightly when processing alot of information.

No it doesn't work that way technically. The ECU samples the sensors around 250 times per second. The JB4 is programmed to read and adjust the sensor outputs around 400 times per second to ensure it's always ahead of the ECU's sampling rate. The JB4 outputs the same sample rate/algorithm whether it's on map0 or any performance map. If it didn't then the ECU would throw a code for a lazy sensor reading.

The "lag" you're feeling is common with more aggressive tuning. Since the boost target is higher torque peak is shifted higher, giving the effect of less response. But at no point are you ever making less torque than stock. It's just a mind game. Intakes also have the same effect. For example it's not technically possible for a turbo intake to cause "turbo lag" but people feel the revised torque curve and believe it to be the case.

 

[Pnbnationsbest]

Flashing is troublesome when u want to revert back.

Not if you have a handheld interface...you plug the handheld in and revert to stock...............................................

 

[StungBlueGT2]

No it doesn't work that way technically. The ECU samples the sensors around 250 times per second. The JB4 is programmed to read and adjust the sensor outputs around 400 times per second to ensure it's always ahead of the ECU's sampling rate. The JB4 outputs the same sample rate/algorithm whether it's on map0 or any performance map. If it didn't then the ECU would throw a code for a lazy sensor reading.

The "lag" you're feeling is common with more aggressive tuning. Since the boost target is higher torque peak is shifted higher, giving the effect of less response. But at no point are you ever making less torque than stock. It's just a mind game. Intakes also have the same effect. For example it's not technically possible for a turbo intake to cause "turbo lag" but people feel the revised torque curve and believe it to be the case.

Thanks for the explanation and good to know the JB4 processes faster than the ECU.

Also, your “lag” explanation makes sense and kind of what I was trying to explain with the intakes. Less restrictions change the power curve which also changes throttle response, etc.

Thanks for clarifying and keep up the good work.

 

[Regs120]

Flashing is troublesome when u want to revert back.

True but the positives out weigh that one negative by a huge margin. Throttle response, ignition issues that plague our spark plugs, torque management (so you don't smoke your gearboxs and AWD axels), and smoother idles. A good reputable tuner can make sure you're well within the limitations of your car and still have all its safety features enabled. I have seen too many ecoboost's blow up from electronic flash tunes sent over the web. Nothing beats a good old dyno tune and before you tell me they are expensive, keep in mind that you're driving a 40 thousand dollar car.

 

[brancky3]

True but the positives out weigh that one negative by a huge margin.

That can be true but it's not true on this platform yet.

 

[DanD]

I've been experiencing this too. It's especially noticeable when I do something like hard throttle, come to complete stop then hard throttle again.

Let's say - I'm at a stop sign at a busy intersection with a high speed limit. Then the car in front of me goes, so I give it hard throttle (>70%) to quickly scoot up to the stop line, followed by brakes to complete stop (or near it) then WOT to pull out into traffic. And boy... it's like 3 seconds before the car really rips... I've literally shouted "GO GO GO" in my car before feeling like the car finally hit WOT.

My gut told me it was some BS transmission nanny protecting me from doing WOT/Brakes/WOT in short bursts or something. (My colleague described this behavior in his Audi and he hated it)

I tried from a stop to WOT really quick this morning, and did notice the "Throttle" seems to lag behind the "Pedal" by a fair amount. In this situation, I did feel a delay - but it didn't feel as long as in the "WOT/Stop/WOT" situation described above... I'm going to try and capture that in a log too...

 

[rynostinger]

turn off your traction control and try it again

I've been experiencing this too. It's especially noticeable when I do something like hard throttle, come to complete stop then hard throttle again.

Let's say - I'm at a stop sign at a busy intersection with a high speed limit. Then the car in front of me goes, so I give it hard throttle (>70%) to quickly scoot up to the stop line, followed by brakes to complete stop (or near it) then WOT to pull out into traffic. And boy... it's like 3 seconds before the car really rips... I've literally shouted "GO GO GO" in my car before feeling like the car finally hit WOT.

My gut told me it was some BS transmission nanny protecting me from doing WOT/Brakes/WOT in short bursts or something. (My colleague described this behavior in his Audi and he hated it)

I tried from a stop to WOT really quick this morning, and did notice the "Throttle" seems to lag behind the "Pedal" by a fair amount. In this situation, I did feel a delay - but it didn't feel as long as in the "WOT/Stop/WOT" situation described above... I'm going to try and capture that in a log too...

Turn off your traction control and try it again

 

[Terry@BMS]

Most of that stuff comes from the trans module. But, there is always the pedal tuner if you want to try cranking up the gas pedal input gain.