r_1_c32

I am wondering if there's something wrong in my speedshift. When you use the manual mode, do the UPSHIFT happen immediately or is there a delay of ~ 1 sec?

Edit: Title

Accord

In my S500 there is about a one second delay, although the AMG's use a better system. When I test drove the C32, I noticed a small delay, but it was definetly not as long as my S500's. I will be able to give you some more insight on November 10th .

r_1_c32

The reason I ask here is because there's a guy over at c32life.com that mentioned he didn't get any delay whatsoever when he is manually upshifting. Anybody here has the same case? If so, do you use the manual mode very often? thx

FrankW

mine gets delay only when i'm flooring the car. the engine will rev a little higher than change it's gear. the delay is less than 1 sec i think. no delays when i'm driving normaly.

btw another thing is that down shift is more immediate, and the up shift will do the thing like i said above. usually i just left it in the D mode and let the trans shift its self. i heard AMG and many car mag recommand letting the trans do its own shift. you will get better results that way.

Taucher

I am, I believe, the person you a talking about who said there was no delay. I have been paying a little closer attention to this since the post and I notice that there is sometimes a short delay. It seems to occur more when shifting in the lower RPM ranges. If I am in, for example, 3rd at around 3000 RPM and upshift, there is a short delay that does not seem to occur when the upshift occurs at 5000 RPM. I noticed it also has something to do with rates of acceleration. Slower acceleration seems to result in a more noticeable delay. I should have taken a little more time to investigate the situation before posting my response, Sorry.

Carl AMG

I agree with Taucher; it will only happen when are shifting too early for the rate of acceleration or if the vehicle is still warming up. See my detailed message to your question on the C32life board.

Taucher

I played with the shifter on my way to work this morning and noticed the following. As I posted above lower RPM ranges due seem to have a bit of a delay. I tried this: At 40 MPH in second gear, about 3200 RPM, I upshift to 3rd without putting any additional pressure on the gas pedal. The car immediately shifts and seems to "surge ahead" as if anticipating of burst of acceleration. I try this several times and get the same result-virtually no hesitation in the upshift. Considering my car has been problem free for over 12 months and 6900 miles, It could be that I just got a really good one! ( there was a letter from MB in my glove box, thanking me for understanding that they sometimes test cars off the assembly line. It explained that this is why my car was delivered with 53 miles on it.)

Boo2

Damn, you don't drive much either, huh.

Taucher

It's not my daily driver, and I don't drive in winter snow, ice, rain either. Have another car to drive in crappy weather.

JustinTRW

Hmmm, I think this surge you describe is a product of selecting a higher gear, and thus having less engine resistance when cruising at a constant speed. The car is not anticipating anything.

BTW, I agree with everyone that the speed of a manual upshift is dependant on throttle load. Haven't tried it, but is it possible to rev-match when downshifting? I wish the car did this, but I suppose it's just an automatic.

aga

Perhaps this thread is old and dead but I have a similar problem with my SLK32. The actual shifting is very fast, but there is a large delay or lag prior to the shift that is quite annoying bordering on making manual shifting useless.

I have tried to generate some concrete numbers, but they are hand done by the seat of the pants.

In general I think there is a 3/4 second delay prior to the shifting which happens in 1/3 of a second. Or about .75+.35=1.10 seconds to shift.

After one trip to the dealer I think it was closer to .8-.9 total shifting time, but I didn't write it down then.

By comparison I was driving a BMW X5 and timed that. It was approximately 1.2-1.3 seconds. Hardly any difference. That's a SUV!

These times don't seem to change with a cold/warm engine. It also seems to be about the same up and down shifting.

The real problem comes into play on the track where you are in full brake and want to down shift. When you shift the 1 second delay entirely messes up the corner. If you try to plan ahead it's even worse as the computer decides you would over-rev the engine and refuses to shift, even though you would be well within that range after the 1 second delay.

Anyone else have any comments or timings? I have to complain to the dealer again and would like to know where others stand.

Thanks,
Alan