The dual friction Centerforce is a fine clutch. But maybe not as good for the stock flywheel as I had hoped.
I put one in my '66 GT350 early on in my ownership, around 2002 +/-. I had put a vintage Paxton on the car,and believed it needed the DF unit. I was wrong. After about 10,000 miles I decided the DF clutch was much more than the car needed, and had several disadvantages. So I made a change to the Centerforce 1.
Although the dual friction may require less or similar pedal force than a stock 3 finger clutch, that comparison is apples to oranges. A diaphragm clutch design will always give a less or different feel. It's the holding power than is final determination of a clutches suitability. The Centerforce dual friction has plenty of holding power, but at the expense of the flywheel surface. It's overkill for a HiPo 289, and despite the extra HP providing by the vintage Paxton on my car, the extra holding power was not needed.
When I took off the Centerforce dual friction I examimed the flywheel. I was not happy. The stock Ford flywheel that had lasted nearly 40 years without undue wear, was scuffed up and worn unevenly. Luckily it cleaned up with minimal material removal. I am very easy on a clutch, I've never had to replace a clutch on ANY car I've owned due to my driving habits. So I was very surprised to see the flywheel surface negatively impacted.
Although skeptical of its suitability, I then tried the Centerforce 1. As expected the pedal effort was easier than the dual friction or the 3 finger unit. I was pleased to discover it would hold perfectly when the Paxton boost came on, and it remained on the car for the remainder of my ownership, about 8 years / 45,000 miles. I'm sure it's still giving good service to the new owner 3 years after the sale in 2012,
Z