vlix

Hey guys, I seldom post threads on the forum but I have to share this to you all.

I took my 2004 E55 to a shop in Hong Kong few days ago and installed something called Sprintbooster. MAN, what a difference it made to the throttle response.

E55 is no doubt very powerful but I have always wished it were a little bit more "responsive". After installing the Sprintbooster (http://www.sprintbooster.gr/en/), I am very satisfied with the overall performance. No error code whatsoever. They were also talking about it on the C55 forum (https://mbworld.org/forums/c32-amg-c55-amg-w203/141056-throttle-booster-highly-recommand.html#post1530854)

I strongly recommend it to anybody who wants their E55s be A LOT more responsive.

Griffin337

How much??????

dragonAMG

Interesting video... says it's only a 30-second install with no cutting of wires.

dsc

Why did this thread die after the post of the web address? Shouldn't there have been posts by people who bought it, or at least intended to get it?

2MANYCARS

So it's something like the APEXi S-AFC without the wire splicing.

Finny

It's my belief that the reason our little 55's have that slight acceleration delay is due to the passive safety systems number crunching away. Would this plug and play device some how impinge on the safety operations?

Yeah...knock it out to feel more snappy...not!

I really hope this is not the case...

Just stomp on it when the tree is orange, by time it's green you'll be off...

Grumpy666

No, I don't think so. My daughter has an APEXi S-AFC installed in her car. It actually modifies the fuel mapping to change the A/F ratio. I think all this Sprintbooster unit does is plug in-line with the pedal position sensor and intercept and modify the voltage signal to make it more linear. There might also be a little amplification occurring to make it 'feel' more responsive. If so, certainly not worth the asking price.

SS3E55

So in the real world I'm an electronics design engineer with some experience of a/d and d/a interaction with real world process control.

If this device plays with "linearizing" the throttle (as the site implies) it is still the source of the throttle position data to the ECU. In that case the ECU is still doing the same number crunching as it did before. And therefore any safety matters are still there and working albeit on modified position information.

In thinking how this might work it seems the only avenue left to the designer is exactly the opposite idea. That is to make the throttle non-linear! But in a special way. This could be done in the "mirror image" of the current relationship (actual position to reported percentage open) completely undoing any non-linearity set in by M-B...and why would M-B have done something like that??? And this is where your comment really applies - perhaps to actually delay the onset of throttle a little to avoid the "shock" of all that tq coming on at once. (good from standstill, not good on a roll)

Simply undoing this decision might lead to "enthusiast" style throttle response (indeed perhaps "scary" to some).

After all the marketing folks might have had some reluctance to have a "touchy" throttle associated with the otherwise (non-amg that is) sedate E class.

BTW - when we have non-linear sources of data from some senors, we deliberately map the reported input to new value which will actually be used (either with a polynomial fit, or some form of piecewise fashion) in a way to mitigate the non-linearity of the sensor (some sensors are just plain non-linear and there's no getting round it in the sensor itself, plus its cheaper today to do it in sw)
...interestingly pots and other position sensors are relatively easy to be made inherently linear...which again implies perhaps M-B uses a linear sensor but modifies its effects to be more "acceptable"...perhaps a little dead spot and a little less agression at first.
...and then this device could effectively reverse those and appear to make the car super-responsive ('cause it is!).

vlix

it should be around US $200

it took me two days to get use to the new "aggressiveness" of the car.

i have absolutely no idea how it works, but for what i care is that it really made my car became more responsive. there might be a cheaper way to do it, but i am happy of what i've purchased.

MikaelSS

Sounds like a waste of money.

dsc

In case anyone is interested I emailed the company for info on pricing. Here it is, 226 Euro is 285.52 in US plus shipping.

The price for Sprint Booster is 226 Euro and it is available in two versions
for Mercedes. One for manual transmission (BDD 451 ) and one for automatic
transmission (BDD 451A) .
You can purchase it directly from our company in case we dont have a
distributor in your country. In this case you will have to pay the shipping
costs which are not included in the above price.
If you want to inform you about the shipping costs or the distributors
network please provide me your country information.

Best Regards
Stamatis Boulekos

dragonAMG

So who else is going to try it?

Finny

Brilliant response SS3E55, You have set a good example here!

Now that you have provoked my thought further... I'm wondering if our AMG cpu I/O's are A, D or a combination?

In regards to the throttle position sensor module (Via foot control not the butterfly on the donk), would this have its own hardware map? (hence the use of the above mentioned after-market map manipulator stand in)

..."or" a linear curve out to A/D or whatever to the cpu, then software map manipulated to give a certain feel to individuals that hate the feeling of sudden inertia by using an exponential type acceleration curve?

Why buy an AMG Merc in the first place, go safe and buy a BM or a Ford if you don't like the stomach left behind feeling...I'm not being a stick in the mud...I'm really addicted to the excessive Nm that our toys put out.

Knock knock...AMG! What were you guys thinking?... please explain!

Anyway...if s/w is the case... why not change the curve to be more aggressive and bugger off the bodgie hardware patch with all the mucking around associated with installation.

Wouldn't this be the way to go?

Basically I'm very fond of ABS & ESP and would be very annoyed if I wrapped the car around a pole just because I wanted a snappy feel.

Having a lead foot, I do find the delay mildly annoying and if there is a "safe" solution, I would purchase.

Can someone enlighten us?


Cheers,

Finny.

vader

I wouldn't mind a little more "feel" of throttle response if this is the way to go.Throttle tip in is kind of lazy......but unless one of you engineers guys can unravel the mystery I won't do it.

Fast55

All sensor inputs are obviously analog. It doesn't matter if the ECU is digital and converts the signal or not. This device just changes the resistance value of the TPS signal to the ECU. A very old trick on electronically managed cars. The difference is that the ECU thinks the throttle is open or closed farther than it really is. This $5.00 "resistor trick" did improve throttle response in my 2001 Dodge Ram truck, but really, it's not worth $300.00 just because it's for a MB.

dsc

OK, so is there any $5.00 substitute for this? I'm analytical in nature and "know" that my car may not be going faster. And "know" my car is faster than most out there. But I do like the "FEEL" of fast and if I can get more in my E55 than I want it, without sacrificing safety.

So what is the substitute?

Fast55

That's the reason it's $300.00. Somebody already went to the trouble of deciphering the pin outs on the TPS sensor, playing with alternative values that do not cause a MIL, and packaging it all in a $300.00 case. Depending on how valuable your time is, that might not be a bad deal. For a car that already has pretty damned good response, it's not worth it to me since there is zero HP and torque gain.

Grumpy666

Are you referring to the resistor that was used for the IAT sensor on these trucks?

Fast55

Similar trick, but it was just as effective to move the IAT sensor to the intake tubing from the manifold to "cool" it off a little. All these "tricks" don't add up to much, but they do change how the motor reacts to throttle and IAT inputs. I'd like to try this myself to see how the K motors respond and if it will "unlearn" the change like the POS Jet piggy back chip for those same Mopar applications. Nice change when you plug it in, then after about 20-30 KO-KO cycles, it's right back to stock. Just can't see blowing 3 bills for the test.

Grumpy666

Yeah, I recall helping a guy with a Dakota that had a Superchip program installed. It had detonation issues at WOT until we inserted a resistor in the IAT sensor line. This fooled the ECU into adding more fuel because it thought the IAT was cooler, which eliminated the pinging. It took a couple three iterations to find a value that wouldn't set IAT Out Of Range code. Moving the sensor to the air box also worked well for those that added superchargers.

Finny

Some sensors like opto isolated transducers which convert mechanical position via infrared beams being cut of with a rotating gapped disc or whatever then outputting this movement data in digital form directly to the cpu/ecu. The A/D process happens with in the transducer itself.

I wouldn't be sticking resistors in line unless I knew exactly what method mercedes were actually using...

So does any one here know which one?

SS3E55

Finny - thanks for the kudos on the larger psot I made.

Finny again you have good points here - optical sensors with interruptor wheels are inherently digital representations of position (count from a "zero" to a position)...although of course in some sense ALL transducers are analogue...this style never simply reports a value in itself. It requires something else (the CPU) to figure out a position. (this is often used in linear position systems in numerically/computer controlled machining)

The resistor trick is a single point of adjustment (effectively you are raising or lowering the entire curve of the graph of position vs reported position).
Whereas this device could (and this might make the price more understandable) have used a more sophisticated adjustment. Effectively a graph (I need pictures here) that has "correction" everywhere and corrects position differently at various points (crudely it would be like having multiple resistors switched in and out depending on the position of the throttle). The effect could then be to have lots of apparent throttle movement for little pedal movement at the start .. and more normal in the middle of the pedal throw....and even less aggressive than stock at the nearly WOT position. Or indeed whatever pattern you wanted.

None of these tricks increase HP for sure...but they might increase the rate at which more HP is applied...and that could integrate into better times. There's nothing here that in theory you couldn't do with a really well trained foot. You could move the throttle quickly to where this device is faking it to be.
The point is the responsiveness is changed and that feels better.

DocStone

Hello;
Need some help. Purchased sprintbooster. Have same car... 2004 E55. Do not know how to remove pedal to install. Could anyone help me?

Thanks
steve

2MANYCARS

Hmmmm... interesting little sucker, I wonder if any tuner out there can do it in a safer way such as modifying the throttle input value to improve the responsiveness...

dragonAMG

This thread died off and I'm curious to know if any other E55's have installed this device and if so, what are you impressions. The C32/C55 guys all swear by this device.