99lightning

im looking at my last dashdaq log looks like on shift its 93% I thought the tcu tune was suppose to not make the tb close.

Rocman8

I don't have the tcu tune and my throttle will go to 80% on a shift so maybe the tcu tune just doesn't close it as much.

Hulk

Are you logging via zt2 or obd? With zt2 you will actually see less than 93%. I have some logs that it closes close to 89%. It is an ecu thing not tcu. I have seen logs from 2 different sl55 and it doesn't close at all

Hulk

There's actually a few threads on this already

99lightning

through the obd port I will see what I can dig up.

Hulk

With zt2 you will see real time and it drops to 88-89%
Sucks losing lots especially trap

Denroll

I've logged it a few times with my Zeitronix stuff and I show it closing slightly to the low 90% range very briefly. I'm tapped right into the wire going to the ECU, so it's an instantaneous readout. I'm not sure the refresh rate over the OBD II port would be fast enough to pick it up.

cnterline

Mines tapped into wire also and it's always around 85% shifting ,I'd love to find somebody to change that ,I was told nobody will or can do it ,or if left at 100 % trans won't last long lol
I have a TCU tune and that just lets it rev higher

99lightning

I think it not closing at all would be better, not sure if can be tuned for that.

DVC

I wonder how much difference a modded valvebody would actually make if the TB is partially closing. Doesn't seem like it would be near as effective as it is in applications where the throttle position stays at 100%.

Ugh, cable throttles FTW.

cnterline

I think 100% on shifts would be �� Trans ,but would be fun for a few hours I guess

DVC

Good point. I'd imagine if it could be safely done, Kleemann would have done so.

99lightning

Oh f that trans. I'm sure it will be fine. Just like my lightning at the time stock block watch those rods 18psi later from 06 till now no issues.

Hulk

Cnterline you are not understanding... You have an sl55 it doesn't start dropping slowly until the shift. The E55 will actually start dropping before the actual shift. At shifts it's completely normal to drop, it does that to protect the transmission

cnterline

Car takes .40 seconds to shift ,every gear ,TPS is hard wired to Zt2 Zt3 Dashdaq XL ,TPS is at 99 % WOT on typical QTR mile run then throttle rolls back to 85% during shift,then rolls back up to 99% ,this is done so tranny doesn't go up in smoke, I understand fully ,asked Kleemann 2 years ago to leave it at 95 % NFG

Hulk

Obviously it is done to protect the trans. This is an ecu issue. The E will always start closing the tb as much as 88-89% then shift, the sl55 and even slr stays at 99% and then shift. No tuner has been able to fix that in the E unfortunately.

whipplem104

There are two reasons why you see it pull throttle at high rpm. One is you are approaching your rpm limit at a rate that cannot be handled with timing alone and they do not want you to hard hit the limiter.
On tq reduction for shifts it is similar that we reduce power at the beginning of a shift. You may not feel it shifting yet but it is in progress. There is somewhere around .2s of pressure control and fill before a shift begins that you feel. We want to reduce power right before to start the shift at the lowest power and then as the shift completes ramp the power back in. By the time ratio completion is done you are back at full power.
Some brands do a set time of reduction but Mercedes does not. The amount and duration is based off the shift itself. It does get more noticeable as the transmission wears out and shifts take longer. It is a learned amount as well.
There is no gain in quarter times by turning any of this off. And it is hell on the transmission. We have run the same car both ways and it is not measurable in ET or trap speed. Because the car is still accelerating during the shift itself from inertia and it is also still make power. Just reduced power.

1ForcedBenz

I think its humorous how some think that the slight closing of the throttle is causing the car to be measurably slower. Such as the repeated statements about the SL & SLR "Doesn't do this" and no tuner can solve the W211's. As stated there is no discernible difference with one that does / doesn't so I'm not sure why someone would consider it "unfortunate". And even comparing that one fact of TPS and not having the full scope of what every other comparable inputs/outputs (timing, bypass valve positioning, temps, knock, numerous others" between the models makes this a pretty baseless comparison anyways.

Hulk

This affects cars that are modified with a bigger tb so lets take for example a car with an 82mm tb.

Every shift the car makes instead of having 82mm NEAR shifts (we are not talking about at the shift) has 10% less, that will be a 73.8mm tb. When passing the end of the 1/4 mile the car will be passing the trap with a 73.8mm tb, do you think that affects mph trap?

cnterline

nanayaw6

06 E55 here with ZT-2 tapped into wire going into ECU. At WOT i am at 98%. Right at 5800 rpm to 6400, it closes down from 98 to 90% then dips down to 80% during the shift then back up to 98%. On mine I believe the closing from 98 to 90 is what happens in that delay time where i hit the upshift button until I actually feel the shift.
Mine did this with both 74mm and now the 82mm. The more power i've made over the years the more I notice it from head jolt. It's almost like being in a high horsepower stick shift.
I rebuilt my tranny this past December so its just the throttle closing annoyance on mine.
I assume this is one of the things a TCU tune would change.

nanayaw6

Hulk, with the SL do you know what it closes down to during the actual shift?

Hulk

The closing will always be there at the shift. I think I am talking about something different, let's say first gear is going to the next shift ...before the actual shift the tps gradually starts closing until the shift and then it goes to 85% for the shift then back up but you will notice the gradual closing BEFORE the shift. The SL or SLR doesn't do that. So in essence on the E instead of the tps staying at 100% before the shift (85% let's say) it gradually starts closing until the shift.

1ForcedBenz

Hulk, I understand what your saying. There is a precursor which is the closing of the TB while approaching the shift, not just when the shift is taking place. My point is that without all the parameters being logged for instance, on "SL SLR" vs the E there's no way of saying the car is losing ET vs a SL/SLR. Maybe the SL/SLR has a different bypass valve strategy, TC lock up strategy, timing, fueling, etc while approaching a shift.

Hulk

Seen cars with same mods same thing

Take a stock for stock E vs SL and they will show the difference. Can also be a reason that the SL was rated higher hp