I have been reading a lot about sprint boosters here on the site. I hear everyone saying they feel the performance boost in the seat of their pants, but has anyone every tested the reaction times ie: 0-60, 45-60, quarter mile, etc..? I am wondering if the boosters actually increase these times or just give the feel of faster reaction times.

 

just press harder on the throttle for the same effect of the sprint booster... its all feel an no actual performance gains...

 

It does not increase speed, it reduces drive by wire throttle lag or if you prefer increases throttle reaction time.

 

Pressing harder on the pedal has nothing to do with throttle lag nor will it improve it and you are correct in one respect there is no HP gain but as far as performance gains that depends on ones idea of performance but to me throttle response is a performance issue and the Sprint Booster does a great job of improving the response time.

 

LAG = TIME

If the tree turns green and your XF thottle response (reaction) time LAGS, your over all time (ET) from start to finish will be longer. YES?

SPEED = DISTANCE / TIME

If you add a sprint booster and eliminate throttle lag (as many members of the forum swear by) would you not also be reducing TIME from start line to finish line?

In the equation above; the lower the time (with distance remaining equal i.e. "1/4 mile") Speed (measured in ET) will increase.

I'm pretty sure Don "The Snake" Prudhomme explained this on the Speed Channel once - the dragsters call it reaction time.

While the SB won't increase driver reaction time, the overall top speed of the car or increase HP etc.. - it SHOULD increase throttle reaction time as you stated above.

I think this is what (1/4 mile times) hudsonc8 is asking.

 

All I know is that when I press the pedal, the car responds quickly and the boost gives me a feeling of more power. This car is a blast to drive. Hands down...just a blast to drive.

 

Brianbrave, I thought I answered his question.
"I am wondering if the boosters actually increase these times or just give the feel of faster reaction times."
by stating
"It does not increase speed, it reduces drive by wire throttle lag or if you prefer increases throttle reaction time."

There have been many posts as to the function of the SB and what it does and doesn't do and I suppose it could or maybe does increase the "whatever mile" ET but it was not designed for straight line drag racing, only throttle lag. I don't know of anyone who has done a timed before and after run to see (if they have I missed the post) but maybe here is a quest for someone who wants to drag race their XF, do a before and after and post the results. There is a racer (road racing I believe) on the forum who felt the SB made his throttle to responsive for the type of racing he is involved in and I believe he has removed it at least for racing but another racer with a SRT does use his while racing so it's a personal like or dislike but wait that is the answer it is a personal like or dislike and there is no right or wrong as long as you have correct information to start with.
If you feel your XF hesitates when you take off from a stop or go to pass someone the SB will correct the TPS response and the only complaint I have heard is it is to aggressive to a few but not many. IT works.
If you are wanting more HP the SB is not your answer as there is no HP gain so you should talk to someone like SI about an ECU remap, a real verifiable proven by a dyno horse-power gain.

 

Here is a simple way to explain what the SB is all about. This is just an example at one giving position of the gas pedal. I haven't actually measured TPS vs throttle plate opening with and without SB, remember that this is only an explanation. FYI: I don't have an SB on my car but would like to try one
Without SB: 50% displacement of gas pedal = 50% throttle plate opening
With SB: 50% displacement of gas pedal = 100% throttle plate opening

Now the real question: How much time are you going to gain at full throttle on a 1/4 mile timed run with the SB? IMO not very much, even if the throttle plate is fully opened at 50% of gas pedal displacement and its probably not (more likely 65 to 75% for driveability at lower speeds) How many milliseconds will be gained when you smash it to the floor to go from 0% to 100%? That is the question?

 

I'll pile on to what PaulW said.

If you're going to be drag racing your car, reducing throttle lag probably won't help, because you account for that in your launch. Once you have a good feel for how your car responds... you watch the tree and react appropriately. Throttle lag is not an issue, really.

So basically, if you're driving around town and find that grandma in her Buick is getting off the line faster than you are (or that punk kid with the Audi A4 2.0), you might want to drop one of these things into your car to help you move off the line a little faster.

 

Thanks for everyone's response, I agree with BrianBrave, if the lag off a tree is not there with a SB - your quartermile times should be quicker. I also wonder for 45-60 mph passes. If you are cruising the interstate and stomp the pedal - the lag is time that you are wasting. I am considering getting a SB, it appears that those on the web-site either love them or hate them.

Those of you with one, have you seen your gas mileage drop off?
Does the SB void any part of the warranty?

Anyone wanting to sell one for an automatic?

This site is great!

 

I guess the simple explanation will be:

If you lose the 1 second lag when you floor your crossfire with SB during the launch, I believe you gain 1 second in your overall time.

Without the SB, you lose 1 second from the throttle lag and is already behind 1 second in the race.

 

It sounds more like:
w/o SB: 50% displacement of pedal = 50% throttle plate - 1 sec.
with SB: 50% displacement of pedal = 50% throttle plate - 1/4 sec.

 

In response to 'hudsonc8' regarding gas mileage drop off...
Yes, you will see a drop in gas mileage initially - you'll be playing a lot more.
Once you stop/reduce the playing, it will return to normal.

Regarding warranty issues - No, remove it before you take it in for any service work if you're concerned.

One thing I will be interested to see is whether putting the SB in reduces the life of the rear tires - mine seem to be disappearing quickly!!! (partly due to playing!)

 

Agreed. If you eliminate the lag, that time is it lagging would be gone off your time. Giving you a better time. Its not a matter of giving you 100% throttle at 50%. Its a matter of it reacting faster. 50% is still 50%, it just gets there quicker, making it seem like its giving more gas, because if you give it 50%, you will keep accelerating for a while, but with SB you will get there faster. Making it seem like more gas.

 

Also, keep in mind that with a Sprint Booster installed, you are limiting the amount of 'Grandma' time that your ECU sees from the accelerator pedal position. Therefore it will adjust to a more aggressive driving style and this is almost the same as resetting the Drive-by-wire system each time you get in the car and/or driving aggressively all the time.

The 'oomph' we feel is the lack of the 'subdued' driving profile being used in the Drive-by-wire.

I personally think it really releases closer to 100% of the engine potential all the time... much closer to what we have come to expect from a normally cabled accelerator setup.

Cheers!

 

Hey guys, Your E.T. time will not increase at all due to the fact that your E.T. time doesn't start until you actually break the beam of the tree lights...at least that is how it works in bracket racing...so if you want to see your actual E.T. time, do it on a bracket racing setup, that way you get the time of the car and not the delay that it takes for you to push the gas pedal.

 

I'm new to the Crossfire and find this discussion about the Sprint Booster very interesting. The existing throttle lag in this car is the only thing I really don't like about it, especially when trying to downshift - I hit the gas pedal to bring revs up and they just don't want to come up quickly enough! Heel and toe downshifting is especially tricky because of this. I'm just coming off a Mazda Miata and the throttle response was almost instantaneous in that car.

But it seems most of the comments here are based on using the SB on an automatic equipped car. Mine's a 6 speed. Any specific feedback out there when coupling the SB with a 6 speed? I'd love to be able to blip the throttle again but right now a quick stab at the pedal seems to give me, slowly, just a few hundred revs.

Oh, and what's the trick to reset the drive by wire throttle? I should maybe try this free tweak first, huh?!?!?!

 

Hi All:

I'd like to chime in on this too. I was considering having my ECU "flashed" or "chipped" and adding the sprint booster as well. Is this redundant or will they each add their own up tic in performance? If I have the ECU upgraded is the Sprint Booster still needed to reduce throttle lag?

Thanks in advance for your suggestions!

GassGhost

 

I have the 6 speed and the Sprint Booster.

BIG BIG difference in throttle response. If that is what you are looking for - the SB is the answer.

 

GassGhost,

I had SI re-map my ECU (I love it and highly recommend it) but the remap did not change the throttle lag and I am not sure any of them can because the lag is caused by the TPS sensor and how it reports, the sprint booster attaches to the TPS and changes the data flow. Keep in mind the computer also changes the way the throttle responds because it learns how you normally drive and second guesses your command deciding if that is really what you wanted to do, that is why you will read about resetting your computer from time to time. As a note I have not reset my computer since I installed my SB.