Just installed Sprint Booster!
 

My co-worker told me about sprint booster when he was complaining about his Audi A6 being sluggish and wanted to try it. He bought it for almost $300 and was very happy with it.

I was looking around on Ebay and found one last week, used with no reserve... long story short i won it for $14 haha :D My Co-worker was pissed!!
Even though it was for a 3 series it bolted right up, the guy from sprint said all the BMW's were the same, not sure why they have different part numbers but anywho..

I gotta say, this thing makes a big difference on how the X5 drives. No more sluggish pickup, you have the power available right away. I turned if off and on bunch of times to make sure i was feeling a difference and oh man, im stoked! You can have it off, one press gets you to green which is still a good improvement, second touch is red which is all out. I'll be keeping it in red.

The highway driving is sooo much better now, overtaking cars is a breeze. I will recommend this for sure. The fact that i got it for $14 is even better :)

I am assuming this is like a sport button....I added a similar feature to my 530xi from roskinc which activated "Sport Mode" and tightened up the suspension and steering in the car. Totally changed the dynamic of how the car reacted and felt. Was thinking of changing out the shifter to get the sport function but this seems a bit easier and cheaper.

This is just for the delayed throttle response. Basically your cars power is made available to you the second you want it versus the delay you get, especially noticed on the highway.

OP, what model and engine do you have?

2011 x5 diesel. I was told by the guys at sprint that all the bmw ones are the same. This one was for 3 series but i took a chance in hopes of making it work and turned out it plugged right in.

Some people say that DDE adapts itself again after a while and throttle response gets back to normal.So please monitor it and see if there is any truth in that statement.

Will do! You can always reset it, which i have done before after every few fill ups.

Have it on mine 4.8i it does make a different

I can't believe people fall for this. SB does nothing more than you could do yourself by pressing the accelerator harder or faster!

I guess $14 isn't much to spend though :-)

Not true, i though that way too until now. You touch the throttle and bam! I turn it off and floor it, it takes good 2-3 seconds before it downshifts and starts going.
I don't think i would have paid almost 300 for it, I'd get the JBD but yeah, for the price i got it for its definitely worth it.

Interesting. The pedal sensor is just a dual sensor (for redundancy). One is sending 0-5v and the other 5-0v. There is not even physical kick-down switch. What could this emulator possibly do to speed-up the throttle response except send a full throttle signal when you only press the pedal partially?
As a matter of fact I am annoyed of my X5D transmission downshifting too much, especially at lower gears. If I even find a way to re-program it to keep higher gear I would do that in a heartbeat.

Nothing!

This is what I found about Sprint booster but never tried it myself.Don't know if it will be harder on engine/transmission?
A sprint booster increases the rate of change of voltage vs pedal position. So for a given increase in pedal position, the sprint booster yields a larger increase in voltage compared to when stock. It fools the engine management into thinking you are pushing the pedal harder.

To me it looks like that you are just saving your foot effort to reach that throttle position.

Exactly! Also the DME/DDE may also adapt to more agressive driving and speed-up the response a bit.
Everyone has a different taste, but I will be unbeliveably annoyed if i have this thing installed in my car due to the frequent and unnecessary downshifts happening every time I press the gas.

Take this scenario, where lag drives me nuts: At freeway speed, do mildly hard slow down, as if traffic stopped ahead. Then, without stopping (at maybe 25mp), stomp on the pedal, as if you want to change to an open lane, and need to accelerate fast because traffic is approaching fast on that lane.

In my case, there is this 2-second lag, as if transmission is hunting for a gear. Then, because a low gear is chosen, RPMs shoot to near-max, and acceleration turns out meh.

Even on left-hand turns, I often find myself abandoning the idea to quickly turn when a gap opens, because I know there is this ridiculous lag when stomping on accelerator from complete still. I don't want to get T-boned.

If OP is suggesting that with Sprint Booster, acceleration is instant after pressing on pedal, it is then not the same as simply mashing your foot. In my cases, it does not matter how hard and far the accelerator pedal is pressed. The lag is always there.

So, does sprint booster take care of those 2 scenarios?

DDE, and EGS, adapt to the driving style. It is possible that when always "stomping" signal is sent from the gas pedal sensor they are always on a highest aggressive settings. BUT, this will lead to even more downshifting and even more lag at crawling speeds.
In this situations using partial throttle has better results for me than stomping on it.
The best way to take off quickly from standstill is to do some boost braking. I use to hit the brake and raise the RPM to 1000-1200 and then it takes off like quicker than one might think.

That is what I do sometimes, but still, no one can explain the hesitation. None of my previous vehicle had it.

Let's see what OP says about my scenario.

SB can't do anything your foot can't.

Think about it, its a passive device, all it can do is 'send' say, full throttle when you are actually at half throttle.

I have explained this before. When the diesel revs high on 1st gear there is no load, turbos dont spool and there is no boost. The boost actually appears sometimes in 2nd gear when the engine starts to load. X5's reaction to a sudden gas pedal stomp is even worse. When the required torque(gas pedal position) is less than the available torque (RPM and boost dependant) it unlocks the torque converter, making the engine to rev even higher :yikes: It is even more annoying with a trailer, the engine revs on first gear, but there is no torque available, the car doesnt accelerate and the computer waits for the redline to upshift.
A real flash tune may help a bit, because there is more available torque at any given time and it makes the computer less prone to downshift. With a piggyback there is more torque available too, but the computer doesnt know this fact and acts like normal.

I will try your scenario today and report back.

Ok well i tried the suggested scenario on the highway while there were no cars behind me.
Going 60mph i did a hard stop till about 40 then stomped on the throttle while the SB was OFF. There was a delay and then RPMs went up and car sped up slowly, as one would expect.

Then i did the same with the SB ON in red and i didnt see much of a difference so i guess it doesnt really work in that scene.
Like it was said earlier, i believe it just sends a full throttle signal at slight throttle but i still like it for highway driving. There is something about just touching the throttle a bit and moving as you intend versus stomping on it and moving.

Im coming over from a 400hp 335i so im very used to power being there when i touch the throttle and x5d doesnt have that.

DISCLAIMER: My engine malfunction light is on, power reduced message is displayed because i have 3 codes i need to fix. Im not sure if that had anything to do with the test. Once i fix things i will try this scenario again and report back.

It will either has no power(50hp) or the full power, except if there are serious problems and boost leak.
Mine X5D with the tune has some serious power, even though the transmission delay and downshift problems are untouched. Just need to adapt to the behavior. From a standstill with some brake boosting I did smoke 335i and Fiesta ST pretty badly. After 60 mph the power is there on tap.

Its showing air intake temp and MAF. I changed the air intake temp and didnt solve the issue, trying to make sure the MAF is bad versus buying a new one to test it.

Wrong thread ? :)

In suburban and stop-and-go traffic, I run the transmission in DS. Helps with throttle response (due to higher RPMs) and gets rid of the annoying engine vibration at certain speeds (combination of RPMs around 1,200 and in high gear)

Thanks for detailed explanation. I, a youtube amateur, always thought of a turbo as a "bonus". You get your regular 3.0L diesel engine, say 180hp/280tq. A turbo gets slapped on, gets the numbers substantially increased. If turbo goes bad, you get the bonus removed and still able to drive as a non-turbo diesel.

But, as you are saying, that is now so. With a bad turbo, or situation where it is not engaged just yet, very little power (tq and hp) is available.

Now, I remember when my brother's turbo-diesel Dodge truck had turbo going bad. That thing could barely go up hill in a parking lot; we are talking a 5.something liter engine.

Perhaps should educate myself more on this.

A "bad" turbo generally becomes a huge restriction in the exhaust AND intake paths effectively choking the engine. While it will produce non-turbo power, a lot of it is used just getting fresh air into and exhausting the hot gasses from the cylinders. It really comes down to the nature of the turbo failure, though.