So how much ft/nm of torque does the clutch of the manual supra hold ? Need to upgrade?

[Topperino]

I'm planning on femto unlocking my early 2024 MT EU spec supra. Just not sure if I do it now or later.
The whole package is really expensive (around 5k for unlock + dp + paperwork + install) and now I've seen some posts about people with failing clutches on the manual. Its like some people are having issues with it and some dont.

I plan on going for 480 HP and around 670 NM (around 490 ft) of torque. Thats the legal limit in my country so I will never go any higher. I never track the car but we have no speed limits on highways and I love to rip the car in second/third gear.

Does the OEM clutch hold this amount of torque or should I plan on upgrading the clutch as well (+ another 1,3k Euro :/ ). I know how to properly drive a stick btw.

Thanks in advance.

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[coyfish]

I am at 550 whp and 600tq without any slippage.

 

[Funkjaw]

The answer is a bit of a mixed bag.

There are multiple owners that report their clutch failed before 15,000 miles at stock power levels, or slipped shortly after putting on a tune. Then there are users like coyfish that don't have any problems at all within the 500-600wtq range.

I believe you simply need to go for your power goals and see what happens.

 

[BMWAF]

I ran 550Nm of torque with a JB+ for over a year without any issue. Probably close to 600Nm now on a Stage 2 MHD tune.. still no issue.

 

[Hasan]

My guess, is that if you are careful in the first 2 gears the clutch should be fine. Let the clutch engage completely before gunning it.

Removing the clutch delay valve (CDV) should help as well.

 

[Topperino]

The answer is a bit of a mixed bag.

There are multiple owners that report their clutch failed before 15,000 miles at stock power levels, or slipped shortly after putting on a tune. Then there are users like coyfish that don't have any problems at all within the 500-600wtq range.

I believe you simply need to go for your power goals and see what happens.

Thanks for the replies, guys.

I never had to think about clutches in general. What is the worst thing that can happen if a clutch dies? Can it cause any further more expensive damage ? Or can i just replace the clutch if it dies like I would now preventively ?


@coyfish /@BMWAF I guess you guys are ripping it from time to time as well ?

Thanks again guys.

 

[FLtrackdays]

Thanks for the replies, guys.

I never had to think about clutches in general. What is the worst thing that can happen if a clutch dies? Can it cause any further more expensive damage ? Or can i just replace the clutch if it dies like I would now preventively ?


@coyfish /@BMWAF I guess you guys are ripping it from time to time as well ?

Thanks again guys.

I hope there are good race clutches available for her. I did that with my other rides. Drove em till they were shot, then bought race clutches. Wasn’t even pushing additional power. RX8, MX5 and S2K. Should be the same now for our Zupras ?‍

 

[swrdply400mrelay]

Removing the clutch delay valve (CDV) should help as well.

@Topperino

Agree with this. I think you would have the highest chance of not having clutch going out if you delete CDV.

 

[BMWAF]

Thanks for the replies, guys.

@coyfish /@BMWAF I guess you guys are ripping it from time to time as well ?

Thanks again guys.

Absolutely.. the occasional traffic light drag and numerous spirited hill climbs but nothing outrageous. I don't flat shift, or outright abuse the car.

Removing the clutch delay valve (CDV) should help as well.

Meh. I have had the clutch delay valve removed and I think it's more than likely just a placebo.

 

[Funkjaw]

Meh. I have had the clutch delay valve removed and I think it's more than likely just a placebo.

I do think mechanically, removing the CDV can prevent clutch wear on hard shifts or clutch kicks. That's the main reason I removed mine as I like to drift the car.

 

[MisterSkiz]

I'm planning on femto unlocking my early 2024 MT EU spec supra. Just not sure if I do it now or later.
The whole package is really expensive (around 5k for unlock + dp + paperwork + install) and now I've seen some posts about people with failing clutches on the manual. Its like some people are having issues with it and some dont.

I plan on going for 480 HP and around 670 NM (around 490 ft) of torque. Thats the legal limit in my country so I will never go any higher. I never track the car but we have no speed limits on highways and I love to rip the car in second/third gear.

Does the OEM clutch hold this amount of torque or should I plan on upgrading the clutch as well (+ another 1,3k Euro :/ ). I know how to properly drive a stick btw.

Thanks in advance.

I'm curious how they can legally limit the power your car makes? Do they test your car every year on a Dynamometer?

 

[Topperino]

I'm curious how they can legally limit the power your car makes? Do they test your car every year on a Dynamometer?

Well maybe I explained it wrong but I meant that in Germany you have to get every. single. change. documented and approved by the authorities. After like 500 hp (with the supra, its % based off of stock power) they deny the approval and your car becomes street illegal, you lose insurance etc. There are specific tuning task forces from the police that will inspect your car, they will read your OBD port and collect your ECU for further inspection.

So they can't limit your HP on a technical level but punish every misconduct so hard that you basically stay inside the limits.

 

[coyfish]

I rarely launch the car or do 1st gear pulls but I rip 2nd through 4th all the time. I have not removed the clutch delay valve. I have a pure 800 coming in and am installing the PTB clutch soon.

 

[DC5UPRA]

I rarely launch the car or do 1st gear pulls but I rip 2nd through 4th all the time. I have not removed the clutch delay valve. I have a pure 800 coming in and am installing the PTB clutch soon.

Keep us updated on that combo, I want to do the exact same thing coupled with Do88 IM.

 

[mdpalmer]

I've been trying to track this down myself, with the hope that the OE clutch parts have some published torque capacity, maybe by cross referencing the BMW G29 Z4 manual equipped car or any B58 manual car, but no luck so far.

Assuming the powetrain engineers did their job, the clutch torque limits should be less than the trans itself to make it the weak link.

Found a reference from ZF (see below) I am pretty sure the Supra's gearbox has a rated capacity similar to the GS6-53dz, 600 N*m or 440 lb*ft. I have no idea what safety margins are built into the clutch and trans themselves so its like comparing apples to oranges.

I have a feeling that the people blowing up clutches either don't know how to drive a manual or they abuse them with excessive heat, or crap parts or poor workmanship at installation from factory. Mine grabs as good as it did from day one. I dont abuse mine but I'm not nice to it either.

Quick vid of a launch.


Couple references:
Notes on trans in the Supra
https://bimmerlife.com/2022/04/30/t...ing-a-manual-transmission-but-what-about-bmw/

Torque limits for trans
https://web.archive.org/web/20181011013856/https://www.zf.com/products/en/cars/products_29322.html

Note the S6-53dz internals in the Supra's trans
https://www.automaticchoice.com/en/gs6l50tz-manual-transmission-catalogue?page=4#5202

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