355 F1 clutch slipping

Well what is the wear limit? You have 1.9mm of wear and my WAG is that you are at that limit. Perhaps that's why the ecu says 106% wear. There is computer PIS regulation that is reset by FNA scantool. I have no idea how they work. I wonder how the ecu remembers. There is no battery in there so if you disconnect the battery I would think the PIS would reset to some factory generic point. Does anyone know how these ECU's think? I would imagine there is mechanical feedback to the ecu that tells the ecu about clutch plate wear and alters the slip for it. Then I wonder what you would do if you changed to say a kevlar plate with friction coefficients that the ecu does not expect. I'm not a 355 guy. I have lots of questions.

 

Flash memory. It doesn't need power. Won't reset *anything* on that system by disconnecting the battery for years. You need the scan tool to set the PIS and one other thing (beats me, not my car model). The scan tool is also useful but not required to bleed the F1 hydraulic fluid lines.

As for his slipping clutch...if he only cleaned things up but didn't replace his triple seals, then there is his problem right there. Of course, you made a good point about the wear limit. Could be that, too.

As for Kevlar clutch or whatever...you should be able to continue to adjust the firmness of shifts via that PIS setting. I would just expect different stored PIS values for different clutch materials.

 

The wear should be more on the outside of the disc, and less on the inside (progressively). Your wear looks very strange...mostly in the center? Something is not right. But the disc looks like it is ready for replacement. Strange, mine at 44k miles did not look as worn as yours at 5k.

 

Sorry I'm not getting it. 8.9 - 2mm (wear limit) = 6.9mm You have 7mm In my book you are worn out or if you want to get technical you have 1% left on your clutch. Additionally uneven wear may put you under the limit in some locations. Clutch does not wear evenly because first 355 flywheels have a dish of something like .08" and the difference in speeds of the inside vs the outside change the wear of the material.

And to ND...what would make you think Ferrari was so forward thinking that they would have different programs for different clutch type coefficient of friction materials? I think they woudl set up for the cheap stuff and then make you buy it!

When figuring out how Ferrari does something you gotta think "cheap and fast" and with whatever parts might be handy.

 

That is the cheap and fast way. The PIS doesn't care about clutch material. It just sets how much/when the clutch slips, just as a human judges how hard/when to release a clutch pedal.

Well, set the PIS to a "2" and you are going to get a shift that is different in firmness than if you set the PIS to a "6".

So it's up to *you* as the programmer to set the PIS value. Oh sure, the system is going to behave differently based on different clutch materials, but it is also going to behave differently based on the PIS value that you enter.

And the best PIS value will be different for different clutch materials.

Once set, it is my understanding that the 355's F1 system then adjusts the clutch hydraulics over time based on the detected clutch wear. This is why the PIS must be reset when you install new clutch material.

 

Yup after seeing this you are toast! 2 is the wear limit not the size limit of the plate. Therfore, you are worn out at 7mm's. Before you even think of getting the dealer to set PIS you need to get everything mechanically correct which includes a clutch disc of the proper thickness uncompressed and compressed. It is critical that you follow the last sentence because if the marcel spring is too big you will get clutch drag even if the compressed limit is correct.

 

Here You go. the PIS procedure is in vol. 2 of the WSM.

from what i have read in the WSM there is only a 2 step procedure after clutch replacement:

1. PIS self-calibration (manually set)
2. New closed clutch value (SD1 needed)

vol. 2 is full of f1 info.

i'll be doing my next clutch change without an sd1, when the time comes. i'll let you guys know how it turns out.
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Jay, don't forget to check your pm's

 

What is IO calibration?

What is new closed clutch value?

 

FBB, from what i understand, the new closed clutch value is the thrust bearing position, with new clutch, in closed conditions.

according to the wsm, io calibration is not needed when replacing a clutch, it is used when the gearbox ecu is replaced.

it's all in vol.2. section D
the clutch control strategies are described in section D

 

Holy Crap,
That clutch plate is shagged.
I don't care what the computer tells you, (because if it is not reset when the new clutch is installed its readings are worthless), your clutch is slipping because it is only "gripping" on about 50% of the friction surface. Figure out why that is (warped flywheel/driven disk etc) and you will correct you fault. I assume you fixed your seals.

 

I will have a buddy of mine post pics of my clutch disk with 44k miles...it has a similar wear pattern, but I am uncertain of the thickness. He is busy, but will try and post on Monday. It was working perfectly up until the release bearing failed and I lost all the hydraulic fluid.

Oh, and my car is a 6 speed manual.

 

Jay, good to here everything worked out

 

So if you can adjust the pis who needs the sd1? Can a similar pis calibration be done with the 360?

 

ROCK ON jayz!!! Thanks for posting that. This will help a lot of people.