Clutch # 3 has been removed

Posted by Tom Still On 2013/8/19 20:33:12

We acquired this 55 Deluxe 4 door, 3speed OD, about 10 years ago. The original problem was a spinning driveshaft on a parked car. The third member was replaced with one from an Ultramatic and the car was a very nice freeway driver. The original clutch survived about two months and started slipping. The replacement was original equipment and lasted less than a year. The next one was "Heavy Duty" and survived about a year and a half. I have always suspected that the higher ratio imposed a heaver load on the clutch and increased slippage. In both cases, I duplicated the original specs. As I recall, the first and second set was 10" disk and 10" pressure plate. I have always assumed the "Heavy Duty" set was the same with heavier springs. I was a bit surprised, today, when I saw a half inch unused band on the pressure plate. What I removed was a 10" disk under an 11" plate. I don't know how I missed that the last time. I recall, years ago, hearing or reading that the small V8's used a 10" clutch and the 352's used an 11". It never occurred to me that the bolt circle was the same. I'm off to find an 11" set with heavy springs. How much difference will that extra 16.5sq" make? While the trans is out I'm replacing the seals. Anyone know what the current replacements are? Also the rubber shift fork couplers are a bit tired; I'm considering cutting new ones, any suggestions as to the best material?
I will report progress, Tom