Looking to flash my TCU if possible. There is too much of a lag when shifting. Anyone do it? 08 E63.

 

i feel the same. if i shift 1k before redline sometimes it does not register and bounces off the rev limiter.

 

you all have the 722.9xx transmission. there are a very few people who have the hardware to flash the TCU. Car has to present since the TCU is housed in the transmission.

 

Any one in SoCal that does it?

 

Weistec is not to far. But you are always going to have delay on a paddle shift. It can be sped up but there is a delay when filling the clutch. There are multiple stages of prefill on the clutches before the shift that you feel begins. Typically somewhere around 2-3 tenths of time. If you are at full throttle you need to start a shift earlier. And it will be different for each gear as acceleration rate changes per gear.
The only way to have any transmission shift at redline is to cut power completely. Do the shift and then turn the power back on.
The main things that can be done in any tune is to fill the clutches faster with more pressure and shorter duration and also later in factory software they started running the clutches in prefill all the time. So a tenth or more of time was already taken care of for both the next up or down shift.

 

so would software basically make our 722.9 shift as fast as the later model 722.9 AMG SpeedShift MCT which has Sport+ modes?

 

Yes and no if it can be done. The there are other things going on. So it would be more of a firmware than a tune issue. Also you would have to consider what is in play with the ecu as well in order for the tq management to be correct during the shift.
These things are really complicated and it almost assuredly not a switch to turn on and off in the code.
The bottom line is that if you want to shift this style of setup at redline you cannot. The way I tune WOT shifts is to start shy of my target rpm. And then look at the rpm climb in each gear from the moment the shift begins to when it starts to pull the rpm down. This amount of rpm is then how many I set to be shy of my targeted rpm shift. So say it takes .2s to start the rpm drop. And in that .2s the engine accelerates 2500 rpm. Then if I wanted to shift at 6500 then I would start my shift at 4000 rpm. Now that might be 1-2 shfit and the 2-3 may only accelerate 1900 rpm in the fill time and then to target the same 6500 rpm I would begin the shfit at 4600rpm.

 

My car has had Brabus go through the tcu, and sport mode does a better job (near perfect near as I can tell) of grabbing gears right at redline than the paddles do in manual mode. So it prettymuich stays in S even though the fancy chrome paddles are appealing...

 

Thanks for the help. I drive in S all the time and always shifting early which I hate doing because sometimes I don't time it right. I will check out both.

 

I have a TCU tune and I don't care for it at all. The shifts are really slow and gives me the impression that I have a clutch car. The shifts don't bang at all... bummer.

 

Which TCU tune do you have?

 

EC

 

that's why I had my shift points lowered