So I took the long trip down to MSL performance today to get my gearbox (TCU) remap and have a run on the dyno to see what my stage 2 map was producing.
Unfortunately when the software type on my gearbox was checked by MSL it was found that I had the only one out of the 3 that they could not map with the system that they had (VGS4, they can do 2 & 3). This meant that Acid the owner had to get in touch with someone who has connections with someone in the states who can do these gearboxes, he took a read of my TCU and then sent that off to America… unfortunately due to the 6 hour time differnece this meant a lot of waiting around and then eventually running out of time today. This is going to be addressed hopefully in the next week remotely so fingers crossed this gets sorted soon… one of the reasons I wanted the gearbox map was that I felt like I was getting a little slip when hard on it and using the torque, I’ve also always felt that the Mercedes MCT was the only real weak point of the car.. it’s perfectly fine but just not as good as the ZF 8 speed that I had in my previous Jaguar XFR and apparently the remap smooths things out and makes the box a bit snappier as well as upping the clamping pressure on the clutch to alleviate any slippage.
Anyways that’s the negative bit of the day out of the way and onto the dyno run… it’s fair to say we’ve worked out why I was getting some slippage…
The graph below shows all 3 runs and the figures are quoted as wheel horsepower on the graphs. Speaking to the guys there this is pretty much the highest figures they have seen from a stage 2 E63
Here’s a link to one of the runs before the properly recorded dyno runs.
Who did you tune? MSL? Was that an OBD port tune? or did they pull the ECU?
MSL did both my stage 1 and then my stage 2 after downpipes, they tuned via the OBD port. I don’t think there’s any requirement to pull the ECU on these anymore.
Consider purchasing the BB intake. It complements the ECU tune very well. Looking at your dyno trace, that power fall off will be negated by the BB intake.
Consider purchasing the BB intake. It complements the ECU tune very well. Looking at your dyno trace, that power fall off will be negated by the BB intake.
already running one, it did make a noticeable difference to the way the car pulled and dragy times came down to suit…
Was there any tuning between the 3 dyno runs? or was that just variation in output? heat soak?
no tuning between dyno runs, as mentioned I do have a little clutch slip at the minute so that accounts for some of it. I don’t think the variation is too massive between the runs really, the dyno and the engine won’t perform identically every single time I guess
Have them check your waste gate duty cycle. We've seen this number come down sufficiently to warrant a retune. Not only did the horsepower not fall off like previous to the intake install, but the tweaked tune made a little more power everywhere.
no tuning between dyno runs, as mentioned I do have a little clutch slip at the minute so that accounts for some of it. I don’t think the variation is too massive between the runs really, the dyno and the engine won’t perform identically every single time I guess
The peak numbers are pretty close, but low end there is almost 180 ft-lbs difference at 3000 rpm.
But agree that run to run there will be variation.
I agree that a difference of 180 ft-lbs is likely ECU pulling timing / dropping boost in response to inputs / or the transmission slipping.
What kind of 1/4 mile times or 60-130 mph times are you putting down?
The peak numbers are pretty close, but low end there is almost 180 ft-lbs difference at 3000 rpm.
But agree that run to run there will be variation.
I agree that a difference of 180 ft-lbs is likely ECU pulling timing / dropping boost in response to inputs / or the transmission slipping.
What kind of 1/4 mile times or 60-130 mph times are you putting down?
1/4 times aren’t great due to being RWD I’ve done an 11.7 @ just under 125mph, that’s partly down to me not doing them very often and a lot to do with the lack of traction, 60-130mph my best is 8s dead with a 100-200kmh time of 6.8s… I am expecting improvements on all of these when I can get my TCU sorted as well. On the run with the green line the RR operator did say that he wouldn’t count that one as there was slippage etc. So that probably explains that I would imagine
1/4 times aren’t great due to being RWD I’ve done an 11.7 @ just under 125mph, that’s partly down to me not doing them very often and a lot to do with the lack of traction, 60-130mph my best is 8s dead with a 100-200kmh time of 6.8s… I am expecting improvements on all of these when I can get my TCU sorted as well. On the run with the green line the RR operator did say that he wouldn’t count that one as there was slippage etc. So that probably explains that I would imagine
Thanks for the response.
I am sure that those numbers will improve with the TCU tune.
Putting down a 11.7@125 in a RWD with big power is still impressive.
I am sure that those numbers will improve with the TCU tune.
Putting down a 11.7@125 in a RWD with big power is still impressive.
8 flats 60-130 is also nice.
Cheers
yeah I deffo think I can get it to hook a bit better from the launch as my 60ft was terrible from what I remember. I think a high 7 second 60-130 is doable as well, I hopefully will get the TCU tune sorted this week and then I will report back with some new dragy times
If it’s lower than the peak torque why will it kill the trans rather than the part of the graph where it makes peak torque? Pardon my ignorance this is just for my knowledge
Got the TCU sorted today which was good, it’s deffo made a difference to the car. The shifts are quicker and smoother than they were as standard and although I’ve been told to give it a couple of hundred miles to adapt the car is definitely quicker and the slip in the transmission seems to be good, I had a quick launch earlier and recorded the fastest time that I ever have and that was with launch control on so it can probably do quicker still.
I had a quick 60-130 run on the road I always use and recorded about 0.1s quicker than I have done but it flagged as invalid for some reason. The road usually shows as -0.75 degrees or so not greater than 1. It’s deffo made a difference though and the car feels better for it.
Slightly better the 0-60mph, the car feels much better with the TCU tune. Still a lot slower 60-130mph shifting on its own in S+ than using M mode though. Approx 1s slower than my best run in manual from 60-130 on this run but I can’t launch it in M mode as quick as it does in S+.
Tried a quick launch on the way home from work today and pulled the best 1/4 time I’ve had with the best trap speed, I let off just before the 1/2 mile time so there’s probably a slightly quicker time to be had there as well… it’s a shame that I didn’t get the best launch as I have done a 3.80 dead to 60mph so that would be another couple of tenths off as well… still not bad for a RWD tank haha
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