Sprint Booster - anyone fitted one?

[S4TAN]

Give me a ring I have one you can try if you dont like it send it back, bet you will keep it.

@ Philip, I will call you now!

... yep - I bet you'll keep it too.

[neily]

Have been toying with the idea of getting one of these for a wee while now...

Phillip - you have PM......

[rikrose]

So, how does this play with remaps on the ECU?

[S4TAN]

Doesn't affect the re-map on the ECU - all the SB does is tell the ECU that your throttle pedal signal value is greater than it actually is - e.g. when you've got the throttle depressed by say 10% the SB tells the ECU that it's at say 50% (numbers used here are arbitrary and for llustrative purposes only - I don't actually know the real numbers, but you get the point) - end result is that the throttle has more attack and gets to the 100% point earlier in it's physical traverse than normal.

[neily]

Some useful info on here....

http://www.sprintbooster.gr/en/

[rikrose]

Doesn't affect the re-map on the ECU - all the SB does is tell the ECU that your throttle pedal signal value is greater than it actually is -
... [cut ] ...
- end result is that the throttle has more attack and gets to the 100% point earlier in it's physical traverse than normal.

Okay. One of the things I've heard about MRC custom remaps is that there's a better response on the throttle. I don't understand where this comes from, however, and one thing I thought of was that there may be a better reponse to the throttle pedal angle sensor. If the map requires the throttle angle sensor to be read for sane input, then how does messing with that input affect the map?

Another query about the maps is where the extra power comes from, and what do we sacrifice for it? I like the smoothness of my unmapped B5. I like that I just did Reading -> Manchester -> Reading, and got 40 to the gallon off it when I wasn't on the M6 Toll road. How badly would I lose out by the new map running wider pulses ot the fuel injectors under low throttle angles? Or is it a more advanced version of "running a bit more ignition timing", to get more power out of the same fuelling?

[S4TAN]

MRC can adjust the throttle map in your ECU (as part of a re-map if requested) to be more responsive and aggressive..

[Doug_S2]

This is a trick - you only get 50% of the pedal travel doing anything. If you move the pedal to 50% it is telling the ecu it is at 100%. Now you have the rest of the pedal travel as a dead movement. So you need to be twice as precise with your foot to make the car feel smooth. and WOT is when you put your foot half way down.

This is an old skool trick on mapped cars to make them feel faster than they actually are. Most of our maps are linear so you get 10% throttle opneing at 10% pedal movement, etc - it gives you the best control especially on track. The more throttle movement at low opneings can be mapped in but most people go back to linear.

[rikrose]

When I finally get my remap (note, it's a when, not an if), it'll keep the linear control. I like it - it works well in my brain.

Earlier today, I had cause to go read the VEMS site again - I thought I could suddenly afford another toy, and was contemplating buying a second car to play wit hthe VEMS ECU in, to learn more about what an ECU does. Unfortunately, I'm not rich enough to be able to afford another (even clapped out) S4 for playing with ECUs with. Ah well. Still really interested aas to what goes on in an ECU in depth though. Not planning on jumping onto the map-making-for-profit bandwagon, but just interested because it's another computer to program...

[SLC Detailing]

Just done a search on the sprint boosters and i came up with this old thread. I now have an S3 and a few s3 boys like these little mods a lot. It seems as though a few people have tried it on there S4's on here. So what your opinion on these now that u have had them on for a while?

[Nige_RS4]

I've had one on my RS4 for around a year now and my own view is that whilst it *may* fool the ECU, the result is very noticable and the end result is a big fat smile on your face. The car feels livelier and I find the audi throttle pedal quite long in terms of length of travel, so it's much quicker to give it full beans.

But I do agree with Doug on one thing - on the track you have to be careful - part throttle is hard work (your right foot becomes very sensitive after time) and once your committed for a corner, you don't want to be lifting off!

I would not recommend this for anyone who does a lot of town driving either, but as mentioned above, you do get used to being more gentle on the throttle and it's been quite a while since I kangaroo'd up the road!

One final thing, contrary to other posts, my MPG has remained the same.

Hope that helps someone.

As a final note, I have no plans to remove mine from the car (with the exception of a trackday maybe).

[grizz]

I'll try your's on mine when you come up .