Clutch conversion of S1 Fulvia

[Huib]

Not that I don't trust you, my friend, but I just counted the teeth on a S1 flywheel. Better safe than sorry. You are right, the S1 flywheel is the one with the 104 teeth.

The hole pattern is for a diafragm pressure plate. Looks like the pattern for a S2 plate.

You mention a thickness of 27mm. If this is the overall thickness, including the pressure table and the interface to the crankshaft, it is the thickness of a S2 flywheel.

It is some time ago I did the conversions. Haven't done them since. I remember that at first I machined the S1 flywheel to the same dimensions as an S2 flywheel. After building all together, I did not have enough free way of travel on the release bearing. Remember that, if the disc wears, the fingers of the diafragm move outward. You want enough free way of travel to move the release bearing back by turning the nut at the end of the clutch cable and still have 1 to 2 cm of free play at the top of the arm. I never understood why I did not have the way of travel as on a S2 car. I just took the flywheel out again and reduced the thickness by 5 mm. In my earlier post I mention a thickness of 21 mm. This is excluding the pressure table and the interface with the crankshaft. If I add those, the overall thickness of the converted flywheel is 22mm.

So why did I need to take of the 5mm?
I just looked at some S2 release bearings, both the older versions and the current versions. The difference in height is only 1mm, the recent ones being the higher.
It might be that the pressure plate I used is different in this respect to the original S2 pressure plate.

What to do?

How about trying with an original S2 pressure plate and release bearing and a disc of minimally 8mm thick?

[Manuel Magri]

I am very tempted to go ahead with this mod. The only thing that bothers me is that the flywheel was balanced with the crank and I am afraid to change it. I have ordered a new stater pinion to see the difference from the one I have because according to my engineer the flywheel teeth are not obsolete but just a little worn out. I also have a rebuilt pressure plate which I bought from Italy and a new clutch so if I manage to keep the original system it will save me alot of money. In the meantime I will show the flywheel to an experienced mechanic for a second opinion. If I find out that the stater pinion is the cause I will install the original system and test the system before putting the subframe in the car. Thankyou all for now, I will keep you posted.

[racing]

You said that the flywheel was balanced with the crank.
What are you doing with the clutch. Be carefull, the standard clutch´s
are not balanced as they should be.

Regards

Andreas