Quoting broxma:
I have the Pressure plate for the stage 3 F1 Clutch sitting in my Garage. The reason it's only the pressure plate is because the Spring popped out of the disc and locked the flywheel to the disc at 45 MPH. What this means is you can't take the car out of gear, and you if you hit the brake the car dies. In addition, You can't move the car, because you can't get it into gear if it's running and if you start out with the car in gear, it moves even when the pedal is pressed.
So I have a Spec Stage 3 clutch now. I gave the Ebay Clutch its shot. It failed after less than 2K at power levels below rated. I will never buy another F1 clutch and dissuade anyone from doing so based on my evidence.
Now, why did the spring pop out. Well the springs are held in by small bent tabs which are basically small cuts of the metal flat surface. The thickness of this surface varies greatly between clutches, with the Spec clutch having a measured close to double the thickness of the F1 clutch. Given heat expansion of the spring, heat expansion of the metal plate itself, any jarring motion on the spring will easily push it through the tab, and lock it against the flywheel. I have pictures of all of this to verify my assessment as I wanted to figure out why the disc failed myself. Essentially, the main supporting face of the Spec clutch is quite a bit more robust than the cheaper Ebay part. This may in fact be the only difference, but it is enough of one that I will not see another Ebay clutch in this garage.
/brox
And that is why I will never own a sprung disk that doesn't have fully encased springs.
Clutchnet or solid hub for me, thanks.