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Sprint Booster for the 2015 Genesis 5.0

Someone correct me if I am wrong, but I want to make sure I understand correctly.

To reach 98% open throttle WITHOUT Sprint Booster, you have to press the gas all the way down WITHOUT activating the kick down. This is difficult because 100% full throttle and the kick down switch are very close to each other, so you would have to get incredibly good at pressing the gas pedal all the way down, but without activating the kick down. This means you actually aren't pushing the pedal all the way down, but 99% of the way down.

To reach 98% open throttle WITH Sprint Booster, all you have to do is push the gas pedal down in the 50-99% range, since full throttle is at 50%. This is much easier to achieve with the additional room you have in the second half of the pedal. This means that the Sprint Booster makes it easier for drivers to get a wide open throttle without activating the kick down.


If the 2 paragraphs above are true, I may be ordering one myself. I have the base model 2012 3.8 sedan, which did not come standard with driver modes like Eco, Sport. etc... That benefit, along with the Valet and Lock mode, AND the easier access to the 98% open throttle, would make the purchase totally worth it.
Precisely.:)

Your understanding of how the Sprint Booster helps with reducing the time to reach full throttle is correct.

So, overall the Sprint Booster just reduces the time it takes to reach full throttle which is about a few 1/10ths of a second depending on the driver foot speed and ability not to the press the kick down switch in the process which would add time to the overall 0-60mph.
 
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Referencing comment #31... So, is W.O.T. triggered by throttle percentage, or pedal position?
 
So who's the brave and courageous person going to be that unhooks their sprint booster or pedal commander, goes to the dealer and asks them if they can detect anything? As a previous owner of a PC in another vehicle, I'd get one for the Genesis...but my previous vehicle wasn't under warranty.
 
So who's the brave and courageous person going to be that unhooks their sprint booster or pedal commander, goes to the dealer and asks them if they can detect anything? As a previous owner of a PC in another vehicle, I'd get one for the Genesis...but my previous vehicle wasn't under warranty.
with it unplugged there's nothing to 'detect'. It doesnt change anything in the software that they could every see, even if they could see any previous logs all they'd be able to see is throttle position which would still only be 0-100%.
 
with it unplugged there's nothing to 'detect'. It doesnt change anything in the software that they could every see, even if they could see any previous logs all they'd be able to see is throttle position which would still only be 0-100%.
iF they could check you're driving history on your ECU, it'd just look like you had a very heavy foot.
 
Referencing comment #31... So, is W.O.T. triggered by throttle percentage, or pedal position?
Kick down switch located on the accelerator pedal assembly I believe. However, not really sure to be honest.
 
Ever since i learned about the restrictive magnetic flap and the delay in acceleration i also came across the info about our kickdown switch.. So i just learned to never just stomp the pedal thats the key. If you can do that you can actually feeel when you are at the switch and eventually it becomes muscle memory. This also eliminated any problem i had whenevr pulling out from turns or into a opening in moving traffic. The sprint booster basically just creates a buffer between your foot and that switch to keep you from reducing your power by activating the switch. im willing to bet i can get to 98% open throttle just as quick as a sprintbooster that only has to be pressed halfway.. only difference is i have no room for error.. if i go to far i hit the switch and am f**ked where as a sprint booster youll be fine because fo the buffer it creates.
 
Why not take a $.10 block of wood and attach it to the back of the accelerator pedal to prevent you from activating the kickdown switch?
 
Why not take a $.10 block of wood and attach it to the back of the accelerator pedal to prevent you from activating the kickdown switch?
The switch is quite pronounced and easy not trigger. You can test this with the car off.
 
When cars go into W.O.T.(wide open throttle), they go into "open loop" and the car dumps fuel like crazy. Also, according to the information in post #31, W.O.T. also shuts the throttle plate a little. Cars are designed like this as a safety measure. A car running rich produces less heat than one that is stacheometric or especially lean. Obviously running rich lowers potential output, but this helps protect the engine, it's fluids, and components from excessive heat damage. My Avalon's AFR at WOT would drop down to the 10:1 range stock. Haven't tested the Genesis yet, but I'm sure it's close to the same.

I serious doubt that W.O.T. mode is triggered by the kickdown switch, but I could be wrong. If WOT is initiated by the pedal being pressed 100%, then the sprint booster is just getting us there faster with no way to stop at 98%. So, in a situation like a race from a dead stop, or a 1/4 mile run, the car might actually accelerate faster without the sprint booster, if it truly makes more power with the pedal pressed 98%.

This is of course assuming that the pedal pressed all the way down right before the kickdown switch sends the signal for 98% throttle, and not 100%.
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I used my Torque app to see what the pedal and throttle were registering with and without the KD Switch engaged. The car was "on" but not running. Sorry, the Torque app only let me see the percentage the pedal was pressed, and the percentage the throttled was opened, not the voltages.

Pressed all the way down without triggering the kick down switch says the gas pedal is at 69% and the throttle is 61.6% open.

Pressed all the way down, this time engaging the kick down switch, the pedal registers 82.7% and the throttle is 85.5% open.

The results were the same with and without the sprint booster. I tried pressing the pedal all the way down then slack off to release the kd switch, and visa-versa. The percentages were the same, and I could not hit any number in between. It jumps straight from 61% to 85%. Taking this data into consideration, I would guess that that last click of the pedal also triggers W.O.T.

So, it looks like the most the throttle will open without triggering the kick down is 61.6%, and 85.5% when engaging the kick down. It'd be awesome if someone else could confirm these number on their car.
 

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So what does this mean for real world driving when you're rarely pressing the pedal to the floor? Isn't that where a sprint booster or pedal commander would work best?
 
So what does this mean for real world driving when you're rarely pressing the pedal to the floor? Isn't that where a sprint booster or pedal commander would work best?
I've had the sprint booster for a couple of months now. Its an absolute GODSEND for every day driving. I have mine set on Sport +9. The car feels a lot less neutered now, passing is effortless, and gas milage was uneffected.
 
I've had the sprint booster for a couple of months now. Its an absolute GODSEND for every day driving. I have mine set on Sport +9. The car feels a lot less neutered now, passing is effortless, and gas milage was uneffected.
As I mentioned before, I am a previous owner of a pedal commander and my thoughts on it for my slow ass jeep are the same as you just mentioned. For me it totally changed the daily driving enjoyment of the vehicle. I can imagine that having one on a V8 would be far more fun.

Also, when sprint boosters or pedal commanders get discussed, it's the same thing on every car forum I've ever been a member of. Those who have never used one always bash them while those who have used one loved them.

Couple of more glasses of wine and I'll probably talk myself into ordering a PC for my 5.0.
 
I went for a drive. The throttle behaves a little different when running. The throttle position still topped out at 85.5%, but I did not have to press the pedal to get there. With the sprint booster on Sport +9, I hit the 85.5% throttle with the pedal only pressed 75% of the way down.
 
I went for a drive. The throttle behaves a little different when running. The throttle position still topped out at 85.5%, but I did not have to press the pedal to get there. With the sprint booster on Sport +9, I hit the 85.5% throttle with the pedal only pressed 75% of the way down.
So no matter what you could not get anything over 85.5?
 
So no matter what you could not get anything over 85.5?

85.5% is what you want. 100% would reduce power.

The idea is that the back and front edges of the throttle plate will slightly interact with the airflow and straighten it out, reducing turbulence and promoting an even pressure across the interior of the intake manifold.

At 100% plate opening you encounter artifacts from the leading edge shearing the airflow, causing pockets of different pressure to form across the manifold and slightly altering each individual runner's pulse airflow performance. It causes a couple of percent efficiency loss at WOT due to the runners not ramming air down into the cylinders the same way. And yes, you can actually see boost air pressure at the top of the valve due to fluid dynamics, which enhances scavenging and further improves WOT performance.

And my argument against sprint boosters is because they're just hocus pocus, with a smattering of lies and a few gullible users. If all they said was "we increase the ramp rate of the accelerator pedal input" they'd be fine. But no, they're hellbent on brainwashing people into believing that they "reprogram the throttle body" and "override manufacturer throttle response." It's all hogwash. And before anyone says "oh you've just never used one"...

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85.5% is what you want. 100% would reduce power.

The idea is that the back and front edges of the throttle plate will slightly interact with the airflow and straighten it out, reducing turbulence and promoting an even pressure across the interior of the intake manifold.

At 100% plate opening you encounter artifacts from the leading edge shearing the airflow, causing pockets of different pressure to form across the manifold and slightly altering each individual runner's pulse airflow performance. It causes a couple of percent efficiency loss at WOT due to the runners not ramming air down into the cylinders the same way. And yes, you can actually see boost air pressure at the top of the valve due to fluid dynamics, which enhances scavenging and further improves WOT performance.

And my argument against sprint boosters is because they're just hocus pocus, with a smattering of lies and a few gullible users. If all they said was "we increase the ramp rate of the accelerator pedal input" they'd be fine. But no, they're hellbent on brainwashing people into believing that they "reprogram the throttle body" and "override manufacturer throttle response." It's all hogwash. And before anyone says "oh you've just never used one"...

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i never said 100% lol i just asked if he ever got any higher than 85.5
 
85.5% is what you want. 100% would reduce power.

The idea is that the back and front edges of the throttle plate will slightly interact with the airflow and straighten it out, reducing turbulence and promoting an even pressure across the interior of the intake manifold.

At 100% plate opening you encounter artifacts from the leading edge shearing the airflow, causing pockets of different pressure to form across the manifold and slightly altering each individual runner's pulse airflow performance. It causes a couple of percent efficiency loss at WOT due to the runners not ramming air down into the cylinders the same way. And yes, you can actually see boost air pressure at the top of the valve due to fluid dynamics, which enhances scavenging and further improves WOT performance.

And my argument against sprint boosters is because they're just hocus pocus, with a smattering of lies and a few gullible users. If all they said was "we increase the ramp rate of the accelerator pedal input" they'd be fine. But no, they're hellbent on brainwashing people into believing that they "reprogram the throttle body" and "override manufacturer throttle response." It's all hogwash. And before anyone says "oh you've just never used one"...

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I have that exact same product from Apexi on my Avalon, and I HATE it. I tried it the first day it was installed, then once more at the track to see if it made a difference in 1/4 mile times(it did not) and that was it. Can't stand it. But like all aftermarket parts, it's worth depends on how well the oem parts perform.

My Avalon is a rev-happy v6 and it was tuned. The throttle is very linear. I started looking for throttle solutions for the Genesis after I couldn't keep up with my buddie's 2006 Charger 5.7 one night. It was after a Mopar meet, he had a bit of a heavy foot, but nothing extreme. If I floored it, I'd cream him, but it wasn't like that. I just could not find the power im the low-mid range. After that night, the dead spots in the pedal REALLY annoyed me.

I started looking for tuning solutions and came across this thread. I remembered how crappy the Apexi Smart Accel Controller was, so I researched the hell out of Sprint Booster before just buying it. The sprint booster appear to be a lot more sophisticated and adjustable than the Apexi. And to be completely honest, there is nothing even close to a tuning solution out there for us. If there were, I would have gone that route. Throttle mapping is one of the things that is tuned on my Avy.

Now I can't say that I would buy a sprint booster for every car I own. Not that the product is bad, but it just depends on the car. You probably don't need it on a Camaro, Mustang, etc... Or any car that can actually be tuned. I can say, without a shadow of a doubt, on the 2015 Genesis 5.0 V8, to call the sprint booster a godsend is almost an understatement. The car FEELS like a 420hp V8 when I drive it every day. I naturally don't have a lead foot, so I have no problem not chirping tires taking off from stop lights, and driving in the rain and snow is no problem. I'm not burning any more gas, so it doesn't have the same effect as flooring the car all the time.

Like I said before, after playing with the settings a bit, I keep my sprint booster set to Sport +9. Anyyhing in Race mode is way to remeniscent of the Apexi. I never wanted, or expected, the car to be faster with the sprint booster, just more driveable. That's probably why I'm so satisfied with it on this car.
 
And here we go again...same on every forum.

I'd love to let someone drive the two vehicles I have used a PC on and let them tell me if they enjoyed driving them more with it or without. No numbers or hard data involved. Just which way was more fun.
 
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