PUNTO INCIPIENTE SLITTAMENTO (P.I.S.) – Understanding Clutch Engagement in F1/E-Gear Exotic Cars
Punto Incipiente Slittamento, or P.I.S. for short, translates from Italian as Slip Beginning Point. Often referred to as the KISS point, this is a critical parameter in the gearbox control module (NCR/TCU) that defines the clutch engagement point.
For owners of Ferrari, Lamborghini, Maserati, and other F1/E-Gear vehicles, understanding and correctly setting the P.I.S. is essential to ensure clutch longevity, smooth engagement, and optimal performance.
What is the P.I.S.?
The P.I.S. represents the actual thrust bearing position at the moment the clutch touches or engages.
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Measured in millimeters within the scan tool parameters
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Directly relates to Closed Clutch Position
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Does not account for clutch wear, but is influenced by:
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Friction disc material (organic, Kevlar, or ceramic)
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Clutch temperature (thermal expansion)
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In F1/E-Gear vehicles, the P.I.S. is the single most important factor affecting clutch performance and wear.
Why P.I.S. Matters for Exotic Car Owners
Imagine you’re at a stoplight, and your F1/E-Gear car is completely cold. You attempt to take off, and the RPM jumps to 2500–3000 before the clutch fully engages. You might notice slight burning of the friction discs or feel the car hesitating — a common symptom of incorrect P.I.S. calibration.
Most owners (and even some technicians) don’t understand the intricacies of these gear systems, which is why proper adjustment is critical.
OEM Recommendations and Limitations
Manufacturers provide guidelines for the KISS point to ensure technicians can service vehicles efficiently. However:
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OEM settings are often conservative, prioritizing reliability over clutch longevity
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They generally do not account for alternate friction disc materials like Kevlar or ceramic
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Factory settings are designed to prevent vehicle rollback or stalling during hot traffic conditions
In practice, most F1/E-Gear vehicles require fine-tuning beyond OEM recommendations to achieve optimal performance.
Consequences of Incorrect P.I.S. Settings
P.I.S. Too High
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Friction discs slip against the flywheel, generating heat and hotspots
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Can glaze the friction discs, causing permanent slippage
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Leads to accelerated clutch wear and reduced driving enjoyment
P.I.S. Too Low
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Friction discs drag on the flywheel, causing the car to inch forward on a flat surface
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Can prevent proper gear engagement, especially under thermal expansion
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May result in jerky starts, stalling, or clutch damage
Tip: Always drive the vehicle for 30–45 minutes before final P.I.S. calibration to account for thermal expansion of friction discs, especially in high-performance engines operating in stop-and-go traffic.
Adjusting P.I.S. for Alternate Friction Materials
Clutches with Kevlar or ceramic friction discs behave differently than stock organic discs:
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Require more initial slip when launching the vehicle
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Should not be set as aggressively as OEM settings
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Driver control and smooth engagement are more important than RPM targets
Example: On a Twin Turbo Lamborghini Murcielago, the P.I.S. had been set too aggressively by a tuner. After adjustments:
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The clutch engaged smoothly at 1100–1200 RPM
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No stalling or jerking during launch
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Proper bedding ensured maximum longevity and consistent performance
Key Takeaways
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P.I.S. is critical for clutch engagement, longevity, and overall drivability in F1/E-Gear cars.
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OEM guidelines are conservative and may not optimize performance for alternate friction materials.
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High P.I.S. causes slippage and hotspots; Low P.I.S. can cause drag, stalling, and gear engagement issues.
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Thermal expansion must always be considered during P.I.S. calibration.
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Proper adjustment requires experience and hands-on testing — not just scan tool input.
Hi Craig
What would you recommend as a good scan tool that would interface with a 2006 Cambiocorsa to bleed the clutch and set a new PIS value?
I’d suggest Texa personally but Autel, is cheaper and also would work.
HI Craig, thanks for a good article. I have a question re the pis . The pis is a distance in mm defining an actual physical event such a when the clutch will actually start to slip when going from being closed. If you enter a different pis value how will this impact on the actual reality of when the clutch starts to slip. For example if the clutch starts to slip at 4.5 mm and you enter 4.0 mm in the TCU what will happen? This doesnt mean the clutch starts to slip at 4mm so what will happen. I would assume the engine torque will be transferred to the transmission earlier than the TCU expects ie at lower rpm and this then would result in an aggressive launch. So the rpm is controlled by the accelerator pedal so could one feather it . Of course the car may inch forward when the brake is released which as you said one doesnt want. Am i understanding this correctly?