a LITTLE link would help.

It multiplies or amplifies or increases the linear pedal output signal by a factor of 1.3, as shown in Fig3, labeled Sprint Booster response. In this test ( 99 SLK-230 ), the actual gain over the oem response curve peaks at about 5X, from 1/4 to 1/2 pedal travel. This is because the oem throttle response curve substancially lags the pedal position curve there, as shown in Fig1.


There is NO graph in the white paper that shows car response. The author mostly discussed the effect of mashing the pedal, in which case there is no difference in car acceleration. This device will not improve 0-60 or 1/4 mile times. I think we agree there.

What does it do ... improves the throttle vs pedal response curve. Put the car on a Mustang dyno, and measure steady state power or torque at 1/4, 3/8, 1/2, or 2/3 max throttle, and the wheel power values will be much higher than w/o the booster.

From a stop, in an atx, snap throttle to any of these pedal positions, and the car will accellerate quicker with the booster.

Some like more power at lower pedal displacements, giving the feel of a higher powered car. Before DBW, GM used eccentric cam pulleys on the carbs to give the same high gain at small pedal motion, and the feel of a larger engine, but little added power was available above 70% pedal stroke, like the Booster.

I might like the fact that the Booter negates the need to use the last ~15% of pedal stroke which has high resistance to motion .... nothing spoils a nice gas pedal feel like a step function change in resistance to travel.



good point, email to the MFG should settle that.


All true, but substitue responsive for sensitive. In the white paper, the phrase "throttle response" is used 19 times

I would suggest the SB simply improves part throttle response.

 

I realize that if I take a car, without sprintbooster, and push the throttle 1/4 of the way down, and then do the exact same thing with sprintbooster installed, that car will accelerate faster.

This is because the SB is simply telling the computer that I pushed the throttle further than I actually did. You can just press the throttle further without the SB and achieve the exact same result, with the exact same lag.

The downside to the sprint booster is that since it is "lying" about the throttle position, once you get past 70% throttle, your gas pedal isn't actually doing anything - you are already at full throttle and have a huge dead spot. What good is this? Look at this graph from the sprintbooster website SHOWING the dead area that it creates in your throttle -

The device does not reduce lag. I honestly wish there were a device this simple that could reduce the horrible lag that Mercedes engineers into their cars.

 

I completely agree with this. I just wish everyone would admit that this is all it does, amplifies the throttle but does not reduce the actual lag.

 

The white paper showed true lag, with or w/o Booster, as minimal ( Fig2, Fig4, and Fig5 )

Fig1 shows lag by design, as the %throttle position curve is well below the % pedal position curve. This lag in expected reponse is fixed by clever use of op-amps.

 

Yes - depends what is considered minimal

Experience tells me that true lag is not negligible & is programmed in - as with the TCU & many other Benz devices including the aircon.

It also tells me that that all ECUs are not set up the same dependent on market where the car is sold.

The first thing ECU tuners do in this country is delete the lag. I've sat down with a young Prof. at one of our local universities & watched him do it on a Benz V6 ECU. It is also interesting that the ECU tune on a Merc is pretty much optimised. It's difficult to improve on. You gain in some areas & loose in others. Some tunes can threaten engine longevity.

acr - I want out of this thread. It bores me to death. That's it.

 

Ok be quit than otherwise we have to baklei
So dont be so befoeterd

about the kappie, in The Netherlands we dont have a kappie on the e

We also havent a deurtrekkertjie here, we call it string

Enjoy your naweek

I love those south african words...

 

So for now im done with this thread, i have told my experiences and thats it...

The power throttle is ready to order, Euro 399,00 + shipping costs
If you want to know more pm me.

 

Gesondheid

Geen bakleiery of geskreeuery of slanery/aanranding nie.

 

Ok skoorsoeker lett it be snoesig!

i am out of here....

 

As I had said in prior post, only benefit of that top-end WOT flat spot would be elimination of nasty hard spot in pedal travel, I prefer linear pedal feel.

 

Lag needs technical definition. The white paper on the SLK clearly shows improved throttle ressponse with the "other device".

 

That was the white paper author's definition, shown in Figs 2 and 5. As he alluded to, most people are really experiencing something else ... different from what he defined and tested as lag. I suspect it's improved throttle response with the Booster. Fig4 shows no significant lag in throttle response with Booster installed. I wish he ran a similar test w/o the Booster.

Always good to find a good tuner. Being a Professor is not a necessary condition ... I've worked with Prof's from the US, Germany, and Russia on different Engineering issues, and in each case I proved them wrong, violating principles of physics.

 

Really the Sprintbooster does nothing at all is it true?

because i am about to install to my C63 2008 AMG and i not sure should i do it or not? after reading what you wrote i am now having second thought?

 

There was also a thread about using an alternate procedure with your gas pedal reset where it doesn't require as much travel to acquire the same amount of speed.

Seems like the thread was titled something about free sprintbooster.

 

That free sprint booster is your own foot. Just develop a brick foot and you're good to go