sleepyca31

Sorry for the recent amount of threads but after reading a super technical thread about the 550 v. 545 acceleration times and someone mentioned calculating the proper shift point for a car-and it is WAY over my head but the conclusion reached was that all cars it is not optimum to shift at redline for max accleration. It happens to be the case in the 550 I read but never hear a mention of the 530. I personally know that if you shift at redline there is a definte lag in between gears and I never thought to shift lower to max out acceleration. I will have to try this.

Just wondering if anyone had an idea of how bedst to shift to gain the best acceleration.

znod

You have a Step right? Well, unless yours works differently than mine, you won't be able to do any serious shifting except at redline. In other words, if you floor the car and get beyond, say 6k RPM, the car will force a redline shift even if you try to shift earlier. This Step "feature" is not cool.

Threads are good. No need to apologize for what is your forum right--regardless of what anyone says.

sleepyca31

Yes Znod it was YOU-sorry to not give you props but after reading about 30 of your posts in that thread I drew a blank on what was your name when I came to making this thread.

BUt wow I have never noticed that-that is pretty ridiculous isnt it-I mean whats the point of a steptronic at all if it is going to force a redline shift for you? I wil have to try that but I am sure it works that way. Come to think of it-I have noticed that but I figured it was just due to the tach rising so quickly and my human eye being delayed so when I shifted it was too late and the tach was already on its way to redline-but what you mentioned makes sense.

That makes me wonder-what is the point of the variosu software tunes out there that increase the redline on cars if it is not always beneficial to do so?

Also not sure how old that thread I was reading but what was your final conclusion with the 550v 545 info you were collecting on acceleration and such-any final numbers?

znod

I concluded that some 545i's and some 550i's are likely to run pretty much the same to 60 and through the quarter--given the same trannys. I also concluded that the Step is the fastest tranny given no rear-end swap for manuals/SMGs. Others have done some side by sides and, to some extent, have found that my first conclusion is likely to be true for some cars. They have tended to find that the 550i's run better from a roll. Neither grogan545 nor I have raced a 550i. I doubt that a shift program would help when it comes to redline vs not redline since, IMO, redline or below is more likely to be optimal. Thus, assuming a shift program would not allow shifting below redline, the main benefit of such a program would be quicker shifting--which could/should make a significant difference on its own.

m630

tis glad to see you back Z, i concur with your findings as usual!!! the step is the fastest tranny when everything else is stock...since i drive mine 99.9% in Manual mode and shift myself, i've come accustomed to how my car and tranny reacts, and can pretty much predict when the shifts will occur...with sport button on and in sport Manual, i can hit the shifter just right to effect the near redline shift on demand, and i too have run very fast and some think i've modded something, but its all stock and all driver, so look out m3, 550 and 650s!!!!!! ! hahahhah