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Transmission slipping? Maybe some other weird thing?

underdonk

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LSPI can be a real SOB.
I thought those were the speed chatters! I understand the principle, but is that really a concern with the B58? I've lugged the engine in the car plenty of times before because I'm a shitty driver and never had (audible) issues with this. Certainly nothing dramatic enough to throw a code, which I imagine the electronics in this car would do if there was something potentially damaging occurring. Note I'm not trying to be argumentative, just trying to learn. I've built plenty of NA motors for track work before, but only one other turbo motor, and it did not have this issue.
 

razorlab

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I thought those were the speed chatters! I understand the principle, but is that really a concern with the B58? I've lugged the engine in the car plenty of times before because I'm a shitty driver and never had (audible) issues with this. Certainly nothing dramatic enough to throw a code, which I imagine the electronics in this car would do if there was something potentially damaging occurring. Note I'm not trying to be argumentative, just trying to learn. I've built plenty of NA motors for track work before, but only one other turbo motor, and it did not have this issue.
It can become more of an issue after tuning when people only tune for WOT or when they just up the torque/load request curve from stock and suddenly the car is requesting 700 Nm at 2,000 rpm.

The Supra ECU has some great logic to help prevent it as much as possible.

My VW's on the other hand....
 

underdonk

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It can become more of an issue after tuning when people only tune for WOT or when they just up the torque/load request curve from stock and suddenly the car is requesting 700 Nm at 2,000 rpm.

The Supra ECU has some great logic to help prevent it as much as possible.

My VW's on the other hand....
Funny you mention it, the other motor I didn't have any issue with this in was a 1.8T VW motor. Maybe I just got lucky, but it was built for track use, and it seemed like (upgraded) electronics and quality lubrication did a good enough job addressing it that I wasn't able to blow it up as much as I tried.
 

razorlab

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Funny you mention it, the other motor I didn't have any issue with this in was a 1.8T VW motor. Maybe I just got lucky, but it was built for track use, and it seemed like (upgraded) electronics and quality lubrication did a good enough job addressing it that I wasn't able to blow it up as much as I tried.
Right, but are you going WOT in 5th at 20mph?
 

BLACK SHARK

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์—ฌ๋ณด์„ธ์š”. ๋ฐฉ๊ธˆ MHD์—์„œ ์ปค์Šคํ…€ ํŠœ๋‹์„ ๋งˆ์ณค์Šต๋‹ˆ๋‹ค. Pure 800, E40, Meth, Xhp ํŠ  ๋“ฑ
๋ถ€์ŠคํŠธ๋ฅผ ๊ตฌ์ถ•ํ•˜๋Š” ๋™์•ˆ ์•ฝ 3k rpm์—์„œ 6๋‹จ์— ๋ฐ”๋‹ฅ์„ ์ณค์„ ๋•Œ ์ฐจ๋ฅผ ์ฒ˜์Œ ์šด์ „ํ•  ๋•Œ tranny๋Š” ์งง์€ ์ค‘๋ฆฝ ํšŒ์ „์ˆ˜(๋ฏธ๋„๋Ÿฌ์ง€๋Š” ๊ฒƒ๊ณผ ๊ฐ™์€)์— ๋“ค์–ด๊ฐ€ ์•ฝ 30์ดˆ ๋™์•ˆ ์ž ๋“ค์—ˆ์Šต๋‹ˆ๋‹ค. ์ž ์ž๋ผ๊ณ  ํ•˜๋ฉด ํŒจ๋“ค ๋ณ€์†์„ ํ•  ๋•Œ ํ™”๋ฉด์˜ ์ˆ˜๋™ ๊ธฐ์–ด๊ฐ€ ์œ„์•„๋ž˜๋กœ ์›€์ง์ด๋Š” ๊ฒƒ์„ ๋ณผ ์ˆ˜ ์žˆ์—ˆ์ง€๋งŒ tranny ์ชฝ์—์„œ๋Š” ์•„๋ฌด ์ผ๋„ ์ผ์–ด๋‚˜์ง€ ์•Š์•˜์Šต๋‹ˆ๋‹ค. ๊ทธ๊ฒƒ์€ ๋‹จ์ง€ ๊ฐ™์€ ๊ธฐ์–ด์— ๋จธ๋ฌผ๋ €๋‹ค. D๋กœ ์ „ํ™˜ํ•˜๊ณ  ์•ฝ 20-30์ดˆ ํ›„์— ์›๋ž˜ ์žˆ์–ด์•ผ ํ•  ์Šคํฌ์ธ  ์žฅ๋น„๋กœ ๋Œ์•„๊ฐ”์Šต๋‹ˆ๋‹ค. 6์ธต์—์„œ ๋ฐ”๋‹ฅ์„ ์ณค์„ ๋•Œ ์ด๊ฒƒ์„ ๋‹ค์‹œ ๋ณต์ œํ•  ์ˆ˜ ์žˆ์—ˆ์Šต๋‹ˆ๋‹ค. ์ด๋Ÿฐ ์ผ ์—†์ด 3-4-5์—์„œ ๋ฐ”๋‹ฅ์„ ์น  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค. WOT์—์„œ 5-6์—์„œ ์ด๋™ํ–ˆ์ง€๋งŒ ๋ฐœ์ƒํ•˜์ง€ ์•Š์•˜์Šต๋‹ˆ๋‹ค.
์ฝ”๋“œ๋ฅผ ์Šค์บ”ํ–ˆ๊ณ  DME์—์„œ ์ด ์ฝ”๋“œ๋ฅผ ์–ป์—ˆ์Šต๋‹ˆ๋‹ค. ์ „์†ก ์ค‘์ธ ์ฝ”๋“œ๋Š” ์—†์Šต๋‹ˆ๋‹ค.

10D000 - ์—ฐ์†Œ ์—”์ง„: ํ† ํฌ ์ œํ•œ์ด ํ™œ์„ฑํ™”๋˜์—ˆ์Šต๋‹ˆ๋‹ค.

๋‚˜๋Š” 608whp์™€ 597tq๋กœ ๋งค์šฐ ๋ณด์ˆ˜์ ์œผ๋กœ ์กฐ์ •ํ•˜๊ณ  ์žˆ์Šต๋‹ˆ๋‹ค.
์ด๊ฒƒ์— ๋Œ€ํ•œ ๋ชจ๋“  ๋น›์€ ์ •๋ง ๊ฐ์‚ฌํ•˜๊ฒ ์Šต๋‹ˆ๋‹ค. TIA
[/์ธ์šฉํ•˜๋‹ค]


 
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tanabersx

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Just for an update my car started with this exact slipping in 6th. Now is CLEARLY slipping no doubt about it. Tranny is going to Pure next week for stage 1, just figuring out how to freight ship it to them.
 

kfer

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Hello. I just got my custom tune done on MHD. Pure 800, E40, Meth, Xhp tune etc.
First drive of the car when I floor it in 6th @ around 3k rpm while building boost, The tranny went into a short neutral rev(like slipping) and went to sleep for about 30 seconds. When I say sleep, I could see the manual gears on the screen moving up and down when I paddle shifted but nothing was happening on the tranny side. It just stayed in the same gear. Switched to D and after about 20-30 seconds It went back into the sport gear it was supposed to be in. Was able to replicate this again when flooring in 6th. I could floor it in 3-4-5 without this happening. Even shifted from 5-6 at WOT and did not happen.
I scanned for codes and get this code on DME, no codes on transmission.

10D000 - combustion engine: torque limitation active.

Iโ€™m at a very conservative tune with 608whp and 597tq.
Any light on this will be really appreciated. TIA
I think you are facing the same problem as me.
The fault code you mentioned comes from the TCU and is a sign of "slipping". But there is another way to analyze the problem. You use MHD, so you can also log. There are 2 important things in this log. The first is the "Torque Limiter Status" - which will show you 1048576 what the limit means.
The other is "torque at the clutch". I think at the point where your transmission starts to fool you, the torque is too low and the above code shows up.
I'm trying to explain what I learned from the xHP guys. The transmission prepares the line pressure for the requested torque (this torque is the value that the DME transmits to the TCU, so the value you see in your log). Since the gearbox (without xHP) has a limit of approx. 550Nm, the MHD tuning (and I guess the others too) does a big trick. It sends lower values than the actual value (around 500Nm in a Stage 2 tune) and so the DME is happy and we hope the gearbox can handle the torque even with lower line pressure. The goal of the xHP would be to eliminate these limitations from the transmission, but having the DME send the downscaled torque readings has no effect. So the slip is there because the gearbox is making line pressure for 500Nm, but you're pushing it at 800Nm. The solution would be to ask your custom tuner to correct the torque readings.
Another alternative could be a Custom Tune from xHP, where they increase the pressure values (e.g. at 500Nm apply a pressure that belongs to 800Nm).

As you can see in my screenshot, before it happens the RPM starts to increase faster (sign of slip) and then the limit kicks in.
At this point I have torque in the 650-700Nm range but DME has only reported 450Nm. When the value was increased to 600Nm the problem went away.

tlimit.webp


tcodes.webp
 
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tanabersx

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Thanks for that thorough explaination. Currently on the break in process for stage 2 Pure. Lets see how it handles. Thanks!
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