Clutch Slipping on stock A91 MT...

[kern417]

Yeah not sure what that was all about. It's like he read the first line of each post and responded accordingly.

Looks like Clutch Masters just dropped their clutch kits for the MKV: https://mailchi.mp/c1cb95297de3/dsg-audi-quattro-owners-rejoice-17034711

https://clutchmasters.com/search.html?fitment=Toyota|Supra|2023-2023 : 3.0L Turbo 6-speed

Cool that they confirm the stock is single disk, so that answers some questions. Hopefully this helps people that will be putting a lot of heat into the clutch.

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[mdpalmer]

It would be nice if the clutch delay valve was electronically adjustable from the cabin ("intelligent" MT after all), or if it could be adjusted manually. Apparently Toyota determined that the production car required a certain level of clutch slip to protect the drive train from shock at the expense of clutch disk/friction surface wear, and whatever other design requirements (making the car an easier drive for MT noobs?).

Thought this was a good read, don't know if someone posted it already:

https://www.zeckhausen.com/catalog/index.php?cPath=6562

I browsed the previously mentioned clutchmasters site and they sell an adjustable CDV/flow control valve.

https://clutchmasters.com/p-35857-hydraulics.html

Apparently some folks making big power (MKIV supras, others) use these.

https://www.supraforums.com/threads/clutch-flow-control-valve.1052594/

For everyone really having issues, please report it to Toyota, at the very least they could issue a technical service bullitien or acknowledge it is a known problem. But before that, cars have to be put down, clutch components inspected, etc... I haven't seen any actual photos of worn clutch disk or flywheel except TJ hunt's abused drift car in the YouTube video, but that one doesn't count as a warranty claim

I have 500 miles on my MT and do find the CDV action kind of annoying, but have adjusted to it. What I've found is that slow, deliberate up shifts, and mindfully not riding the clutch pedal (esp. when in stop and go traffic) results in "normal" clutch pedal feel and drivability. I'm no expert in manual cars but I've had a few manual cars: rotary (OEM and an aftermarket clutch) and LS Rx-7, Gen 2 Dodge Viper, and two Integras (1st car required clutch replacement just under 200k miles, 2nd car I'm still driving with 160k miles and no clutch issues and I beat on it), so those are my benchmarks for "normal" clutch feel.

Will start drivng the supra harder as I run thru the break in. If it comes down to it I wouldn't mind installing an aftermarket clutch without that POS valve, I'd rather go that route so I can properly use the engine torque to go fast 🫡

 

[kern417]

It would be nice if the clutch delay valve was electronically adjustable from the cabin ("intelligent" MT after all), or if it could be adjusted manually. Apparently Toyota determined that the production car required a certain level of clutch slip to protect the drive train from shock at the expense of clutch disk/friction surface wear, and whatever other design requirements (making the car an easier drive for MT noobs?).

To be fair this isn't a Toyota thing. Even my 2009 Volkswagen had one. They've been in german cars for a while.

I definitely agree on reporting it though. Even if you don't think it'll be covered under warranty, they won't get any data unless owners actually go to the dealership for diagnostics.

 

[RenRed2]

It would be nice if the clutch delay valve was electronically adjustable from the cabin ("intelligent" MT after all), or if it could be adjusted manually. Apparently Toyota determined that the production car required a certain level of clutch slip to protect the drive train from shock at the expense of clutch disk/friction surface wear, and whatever other design requirements (making the car an easier drive for MT noobs?).

Thought this was a good read, don't know if someone posted it already:

https://www.zeckhausen.com/catalog/index.php?cPath=6562

I browsed the previously mentioned clutchmasters site and they sell an adjustable CDV/flow control valve.

https://clutchmasters.com/p-35857-hydraulics.html

Apparently some folks making big power (MKIV supras, others) use these.

https://www.supraforums.com/threads/clutch-flow-control-valve.1052594/

For everyone really having issues, please report it to Toyota, at the very least they could issue a technical service bullitien or acknowledge it is a known problem. But before that, cars have to be put down, clutch components inspected, etc... I haven't seen any actual photos of worn clutch disk or flywheel except TJ hunt's abused drift car in the YouTube video, but that one doesn't count as a warranty claim

I have 500 miles on my MT and do find the CDV action kind of annoying, but have adjusted to it. What I've found is that slow, deliberate up shifts, and mindfully not riding the clutch pedal (esp. when in stop and go traffic) results in "normal" clutch pedal feel and drivability. I'm no expert in manual cars but I've had a few manual cars: rotary (OEM and an aftermarket clutch) and LS Rx-7, Gen 2 Dodge Viper, and two Integras (1st car required clutch replacement just under 200k miles, 2nd car I'm still driving with 160k miles and no clutch issues and I beat on it), so those are my benchmarks for "normal" clutch feel.

Will start drivng the supra harder as I run thru the break in. If it comes down to it I wouldn't mind installing an aftermarket clutch without that POS valve, I'd rather go that route so I can properly use the engine torque to go fast 🫡

My post earlier -


Interesting point form a road test back in Jan in the USA . How the reviewer for the magazine found the clutch to be effectively used for good timing.

--For its part, the Toyota likes to be finessed; our 4.3-second time was the result of gently slipping the clutch and slow, purposeful shifts. --

https://www.motortrend.com/reviews/...nual-transmission-6mt-comparison-test-review/

 

[jtsang25]

Do you even English? If its a design or manufacturing fault Toyota should cover it. Simples.

Toyota won't do anything. 2021 had oil consumption issues they tried to fix a few, think some got a new engine, some dealers bought them back. But Toyota never officially announced it as an issue.

 

[FuzzyRev]

I wouldn’t say not stock since all of that is more of a placebo effect for added sound. That adds basically no hp at all without a tune and the car isn’t tuned.

I feel like this conclusion is different from what people used to say, and when my 2021 did back to back dyno runs before and after a Titan catless dp, I picked up 21 WHP & 39 WTQ without a tune or any other parts. That's certainly a significant bump, and was very noticeable by the seat of my pants. That being said, is your DP sans meow meow?

 

[UYCR]

Looks like Clutch Masters just dropped their clutch kits for the MKV: https://mailchi.mp/c1cb95297de3/dsg-audi-quattro-owners-rejoice-17034711

https://clutchmasters.com/search.html?fitment=Toyota|Supra|2023-2023 : 3.0L Turbo 6-speed

I'm guessing the FX400 will be the popular option but I have a friend who went ahead and ordered the 1000 series just to be extra safe. He already put on the top mount and is finishing up on the supporting mods so lets see how these things perform with some 1/4 mile abuse. Would have been nice if Clutch Masters called out the actual torque rating for each and actually put in some time to proof read the product descriptions.

 

[Xeros12]

I feel like this conclusion is different from what people used to say, and when my 2021 did back to back dyno runs before and after a Titan catless dp, I picked up 21 WHP & 39 WTQ without a tune or any other parts. That's certainly a significant bump, and was very noticeable by the seat of my pants. That being said, is your DP sans meow meow?

You are in fact correct. Me saying it adds no hp is wrong. My point was it’s not a considerable amount over oem power to say that was the factor making the clutch fail. As I’ve read about the oem clutch people saying they where starting to slip around 600tq, and my those bolt ons alone without a tune will get me nowhere near that number. Thus I said I mainly did it for the placebo effect because I was taking the car to a track and wanted to hear all the good noises coming from the b58.

 

[Sharocks]

I had hoped that it would not have to come to this but this may be the only way you can really rail on the car.

The VW folks are all too familiar with this when you start adding modifications.

Sad part is that the clutch can't hold stock torque.

I didn't buy this BMW to drive it to CNC's and hardpark it in front of Starbies.

Unfortunate. And also unfortunate for the folks that are patiently waiting for their cars and reading this.

 

[FuzzyRev]

I'm guessing the FX400 will be the popular option but I have a friend who went ahead and ordered the 1000 series just to be extra safe. He already put on the top mount and is finishing up on the supporting mods so lets see how these things perform with some 1/4 mile abuse. Would have been nice if Clutch Masters called out the actual torque rating for each and actually put in some time to proof read the product descriptions.

I wonder if that @clutchman guy is a CM employee... Either way I'm very impressed with the pricing actually, and love the various options in holding power and engagement characteristics. That said, it is disappointing to not have solid numbers of HP, & especially TQ capacities of these offerings.

 

[FuzzyRev]

I had hoped that it would not have to come to this but this may be the only way you can really rail on the car.

I just accepted it as such a little while ago, and am going to wait on the major power-adders until I have a new clutch kit standing by on my shelf. I've been in the Import Tuning scene long enough to remember some other vehicles that had so-so OE clutches, and we just stocked up on upgrade kits right out of the gate. It was what it was, and we were never mad when an OE clutch could 'only' handle 20-25% more torque than stock output. How could we be?

 

[clutchman]

I wonder if that @clutchman guy is a CM employee... Either way I'm very impressed with the pricing actually, and love the various options in holding power and engagement characteristics. That said, it is disappointing to not have solid numbers of HP, & especially TQ capacities of these offerings.

I am not, I am from another large clutch manufacturer.

 

[UYCR]

I am not, I am from another large clutch manufacturer.

OS Giken?

 

[FuzzyRev]

OS Giken?

ZF Sachs? Exedy/Daikin? LuK? Aisin? Borg Warner? Valeo?

Something tells me he isn't at liberty or would prefer not to say. I know how that goes..

 

[Evolution]

Clutch Masters is right up the street from me and I am actually good friends with them. Could probably talk them into a group buy if you guys are interested.

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