He’s an Alfa specialist, but dabbles in Maserati too. What is PIS point And how do I get it adjusted? Thanks for everyone’s patience, I’m new to this malarkey.
PIS is the clutch Point of Initial Slip.
Whichever garage you take it to will need either an sd2/sd3 , leonardo or launch diagnostic system.
If when your in gear but static and you increase the revs the car should start to move as the clutch engages at around 1200 rpm. As the clutch wears down from new the PIS reading will grow from say 4.50 to 4.60. Which is 1mm in reality.
The effect you will see / feel on the car is that the gear changes wont be quite as snappy as they should be and the point at which the car will start to move in gear from standing will start to increase upto around 1600 / 1800 rpm. Which can be tiresome in stop start traffic.
Each car is different there is no magic number for the PIS to be set that will suit all cars.
The knack is to have everything warmed up and up to temperature before they take the PIS reading from the TCU and then adjust it down slowly in increments. After each adjustment on level ground check the gearbox primary angle speed and make sure it stays at zero when they select 1st gear or reverse gear without touching the accelerator. If it changes from zero the clutch is starting to drag so the PIS needs to be backed off by 0.1mm so that it doesnt drag.
The aim is to have a tight setting on the PIS so that gear changes are almost instant and the clutch is fully engaged as soon as you put your foot on the loud peddle.
Less slip on the clutch means longer clutch life. It also means your flywheel is less likely to get hot spots.
As and when you get it to an indy to have a look ask them to check the readings and adjust the PIS.
You will probably find it reading somwhere around 4.65 or higher and when set up it will come down to say 4.58.
If your not familiar with the gearbox and clutch on these cars avoid reversing uphill if at all possible. Its a sure fire way to shorten the life of the clutch.
