Please help Auto Trans slipping with E50 Tune and XHP logs included

[Tony11011]

Hi Guys

Just hoping i can get some help here. I have gotten the car tuned again with another tuner who has the car finally running right and making good power, have included dyno numbers below.
But now the trans is slipping in 6th gear only, a revision was done to reduce the torque, the revision was done on the hub dyno and there wasn't an issue on the dyno but it is slipping when on the road. so when hard accelerating from 5th to 6th or from hard accelerating in 6th the trans either slips or slips then goes into limp mode, obviously i don't want to keep doing this and ruin the gearbox so was hoping some one can take a look and what the issue could be.
Ive included 2 logs below, the first log is from the previous tune with no gearbox slip and the next one is the current tune with gearbox slip.

have spoken to xhp and all they have said is to bump up the torque at clutch target to what the hub dyno is reading in torque. But the previous tune was making around 750-780nm and was not targeting that much at the clutch as per the log below. the baffling to me is that they are both very similar in the torque readings and limits for 6th gear.

Look, any help or suggestions will be really appreciated as getting this car running right has taken forever.

Previous tune with no clutch slip
https://www.bootmod3.net/log?id=65bf2ce9a11c9e228574b726

Current tune with clutch slip
https://www.bootmod3.net/log?id=65b99ceb5b715e7741d118b5

Thank you

Anthony

This is the comparison between the old tune and the new tune on E50

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[FLtrackdays]

Is the new tune the one with the massive spike and the sharp drop off?

 

[Tony11011]

Is the new tune the one with the massive spike and the sharp drop off?

Both tunes have a massive drop off the new tune is the one with the 890 nm of torque.

 

[Thraxbert]

The spike and dropoff is the trans slipping and re-catching. The tune needs to keep the torque under 800Nm or it's likely to slip on the stock trans in 5->6. If your new tune is pushing nearly 900Nm, your tuner needs another revision.

 

[KBGT]

Tune revision for less torque down low. Do you have xhp in drag raced mode and line pressure increase turned on?

 

[razorlab]

“My tune went from 700Nm to 900Nm, why is my stock transmission slipping now?”

 

[3literV8Eater]

My tuner advised that no pulls in 6th, 7th, or 8th gear. That is to protect the stock transmission. I understand you may need 6th for roll racing or higher mph but you’re going to have to get the transmission upgrade to play in 6th gear regardless.

 

[Tony11011]

Tune revision for less torque down low. Do you have xhp in drag raced mode and line pressure increase turned on?

I do have xhp and with line pressure bump but not drag race mode

 

[Tony11011]

My tuner advised that no pulls in 6th, 7th, or 8th gear. That is to protect the stock transmission. I understand you may need 6th for roll racing or higher mph but you’re going to have to get the transmission upgrade to play in 6th gear regardless.

It’s more that when I’m on the highway in 8th gear and then floor it. It will drop down to 6th then slip.

 

[Tony11011]

“My tune went from 700Nm to 900Nm, why is my stock transmission slipping now?”

This tuner in Sydney Australia has tuned a heap of these cars all making around 850-900 nm of torque. They are known as one of the more prominent tuners in Sydney
Also in saying that I’m paying for a service so would think they would know how far to push the car.

 

[Tony11011]

“My tune went from 700Nm to 900Nm, why is my stock transmission slipping now?”

Have you looked at the logs with the revised tune? Where the tuner has dropped the torque numbers?
the difference in torque between the two are barley negligible.

 

[razorlab]

Have you looked at the logs with the revised tune? Where the tuner has dropped the torque numbers?
the difference in torque between the two are barley negligible.

That's called "under reporting torque". It's a tuning strategy. It can lead to undesirable effects, as you are experiencing.

The car is obviously making more real torque to the wheels with the new tune.

 

[3literV8Eater]

It’s more that when I’m on the highway in 8th gear and then floor it. It will drop down to 6th then slip.

Only thing you can do is reduce the amount of torque in 6th like others posted or get the transmission upgraded. Mikey Botti tuned my car and it made 700ft lbs of torque on an E50 tune. My transmission has never slipped since I don’t do any pulls in 6th or higher. If I do pulls in 6th gear it’s on a less powerful map that does not make all that torque. ECUTEK is the best imo.

 

[Thraxbert]

It’s more that when I’m on the highway in 8th gear and then floor it. It will drop down to 6th then slip.

If you don't want to revise the tune or build the trans, then it's always going to slip in 6th at this torque. Turn on Kickdown DISABLE in XHP and the car will no longer automatically drop gears when you go to WOT. That means you need to be in 5th gear (or lower) on your own before dropping the hammer.

 

[Tony11011]

Only thing you can do is reduce the amount of torque in 6th like others posted or get the transmission upgraded. Mikey Botti tuned my car and it made 700ft lbs of torque on an E50 tune. My transmission has never slipped since I don’t do any pulls in 6th or higher. If I do pulls in 6th gear it’s on a less powerful map that does not make all that torque. ECUTEK is the best imo.

Thanks for your reply, im happy to have a lot lower torque in 6th gear to protect the gearbox. i dont roll race or do 6th gear pulls, the only reason i noticed this was when i was hard accelerating in 8th gear while on the motorway because a golf R was annoying me, dropped down to 6th then slipped.

Will let the tuner know to limit torque at 6th gear to 750nm (550 lb)and increase the torque at clutch value.
Because im so rarely in 6th gear driving hard im happy to sacrifice some torque.

thanks

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