how do you know the manual SB can't be used with the automatic car? are the connectors different???

 

D,
That's why I asked the question. I don't feel like going through this entire thread to find the info, but somewhere in here there was some discussion about this. Regardless, thanks again for the post.

 

Yeah I remember reading the same thing that you can install a manualSB in an automatic car, but it's not recommended. It's just way to sensitive for an auto I belive.
I cant imagine MBZ using a different conector on for the throttle. if the AutomaticSB version fits the manual car why not vice versa?

 

You could probably install the manual version for an automatic, but it would probably damage your transmission... your risk and your loss if it does.

 

I had sent this before:
For those of you who have recently inquired about getting another group purchase, I bought mine from slkfans.com for $250.00 including delivery. This guy takes paypal. I got mine in 3 business days. This might save you the time of coordinating a group purchase.

If when you click on the link it doesn't work, just key it onto you browser address.

Here's the link to his site. www.slkfans.com

 

Ordered one today...

 

I know by reading and heeding the information from the manufacturer earlier in this thread. The connectors are the same and it can be installed with the automatic if you so desire, but it doesn't shift very well and could very well damage the trans. But it is all up to you, there is nothing to stop you. If you have the 251A, then it can be used in either. If you have the 251 then put it in an automatic at your own risk.

 

Thanks for clearing that for us.

I'm guessing it will smoke the clutches in the auto tranny, because the transmission computer is not calibrated for the engine speed. The manual Sprint Booster might be putting too much power to the tranny too early, and the solenoids in the valve body may not be opening early or late enough to put the pressure to the clutches in the drum during a shift, this off timing might cause some major slippage and burned clutches.
Kinda makes you wonder about the long term effects on those autostick trannies when using the SB.

 

Installed the 451A sprintbooster on my 2003 C32, easy, except for getting the connector off, the release clips are pretty small.

I like the roller coaster feel of the sprintbooster. Its a lot more fun to drive, but like it should be. It would be nice if it was switchable. Currently, I put the transmission on W mode (wife mode) when driving with my wife.

Before the sprintbooster, I always turned off ESP, no more. Even with the ESP on, it lays scratch pretty easy.

The whole reason, I like as much HP as I can get, is for the feeling of acceleration, which is easier to access, around town, with the sprintbooster. The transmission downshifts quicker also.

Need to be careful about traction, now, maybe an LSD would help.

Thanks Jody for all your work.

 

Well I sent Sprint Booster an email. I'll see if they'll reimburse my funds for the Manual version???

 

Ok folks, here's my real complaint about the Sprint Booster. It's a decent attempt to fix the throttle lag which it does well. And I can't put any blame on the 1st gear ratio on the 6 speed, that's not the problem.
The problem I am experiencing is that the throttle is not linear when pressing the pedal. I don't have any realistic way to measure it, but it feels like within 1/2"-1" of pedal travel I'm getting power that I used to get at 80%-100% throttle. I just wanted to remove the lag.

I tried resetting the throttle, but it's still taking off too quickly in 1st. Now maybe I didn't do it correctly, so I will try disconnecting the battery over night and reconnect it in the morning. I'll see if this works but I doubt it.

 

Jody: I got home from a hellish few weeks of work in Charleston an hour ago and amongst the stack of mail on my desk, that my wife so delicately piled-up like a garbage dump , was your package with the Sprint Booster. Just to verify part #'s since I did zero research on this product aside from this forum, I received the BDD 451. Is this the correct part for the manual transmission ? If so, I'll install it over the weekend and try to do some back road, midnight testing before my race weekend.

I'm hoping to be jumping with joy if the SB reacts the same way it is doing on DYNAMIC-S' car. If it is not as "TWITCHY" as he is claiming his is, perhaps I'll just trade him mine... He's Los Angeles based, so it wouldn't be a problem...

But verify my product # for me first, then I'll install over the weekend...

 

Yep the BDD 451 is for the manual transmission and the BDD 451A is for the Auto-Stick.

Happy sprintin!

 

The Sprint Booster is actually improving throttle response by giving disproportionately wide throttle openings for small initial pedal movement. This obviously improves the initial response but can do very little to improve the response over the latter portion of the pedal travel since the throttle butterfly will run out of movement. Exactly like you explain it is giving you the 80% throttle for the first 10% of pedal movement, it can never give better response over the whole pedal travel. This is why I have my doubts that HDDP will pick up any more time on the track; it may feel better out of the slow corners when winding up through the rev range but on the track you tend to be running at higher revs and using a much narrower rev range. I will happily be proved wrong if he reports otherwise though (Good Luck at the Weekend Derek!).

I actually looked into making something similar to the Sprint Booster some time ago but decided against it. I checked the throttle butterfly movement in response to the pedal and there does not appear to be any delay. I think the lack of response is largely a function of the inlet design which is where I am focusing my attention. The other thing that put me off is that the fact that the ECU’s throttle algorithm is still in play and will still modify the throttle response. It would be yet another layer of software between me and the car and decided it is better to fix the inherent problem (not that I have ever had a really big problem with response) rather than try and mask it.

Just for further information here is the service manuals description of the throttle algorithm:
I don’t mean to dismiss the SB as it appears to be a well engineered device that does what it claims and I know there a many owners who are very happy with them, I just don’t think it completely addresses the problem. Just my .02.

 

Holy Moley...I just love the feeling of the booster when I'm driving in an area where I can let loose a bit on the pedal. The response is quick and the "fun" factor kicks in, as well.

I think the majority of us have found that extra zip to be well worth the $$. Gas mileage might be less...but I don't care...

 

I'm not sure how much gas mileage suffers as a result of the SB. I just filled up since I installed the SB, and I'm sure I'm still above 20 mpg.

 

Well my gas mileage isn't that bad using the Sprint Booster. I lost about 2-3 mpg from my usual 22-25 mpg city driving.

I think I might be getting use to driving the car now with the SB, but I had to reset the throttle a bunch of times after every trip in the car. It now feels a bit more tolerable after the throttle resets. Doing so has given me a little more pedal travel (about 2" now) and some dampening for my foot.
It really sucks when your in 1st gear and you drive over a little bump or dip in the road, your foot lightly taps the throttle and whoooaa look out!!!

 

I don't think it will help my times significantly either. I'm actually concerned that, if it is as "twitchy" as proclaimed in other posts, it will make it very difficult to feather the throttle during power slide turns. You know that fine line where you float the rear end through a turn maintaining just enough traction to prevent a full spin... The only way you can do that is with very precise throttle control. So, if this thing gives 80% throttle in 10% travel, I'll end-up spinning like a top on a merry-go-round !!!

We all know what the problem is, low power to weight ratio and no cost effective way to change it !!!

Thanks for the good will during my next event...

 

I think no matter what application the Sprint Booster is used for (manual or Auto-Stick) it will take some time to relearn the car.

I'm just to the point now where I can drive this under almost any condition without making the car 'lurch' even just a little.

HDDP, if fine control is what you need, then you may be better off without it, but I'm still thinking it will help you as the 'feathering' you need to do will be in the last half of throttle movement where this thing actually has more play. I don't think it's quite 80% in the first 10% of movement as Woody states (remember 85% of statistics are made up on the spot ).

I will say the first bit of throttle response will really surprise you, but what I consider the 'control' area is wider. If I was using more power during my regular driving and not just cruising, the throttle would be past the 'twitch' area.

Again, just my thoughts with the 'Auto-Stick' version. It could very well be that the manual is WAY more aggressive, although I think it's just the learning curve everyone has to go through.

 

MMZ: I installed the SB this morning before I went to the studio, since my car is gutted and everything is accessible (sp) it took two minutes...

I'll take the car out tonight after I get off work, midnight or so, and give it a little test and report the results (my perception).