I was going through the old threads to read up on clutches. I think my throwout bearing is going (it's whining) and I figured I should just upgrade the clutch while I'm at it because I've got a GM OEM kit in there that I paid about $100 for 10 years ago. I've done enough research here to know that I should buy a Centerforce for my street driven, stock rebuilt 455 with an M20. Summit seems to list two clutch kits for a ten spline. The first, KCF757116, is a Centerforce I. The second is KDF355216 and I assume this is the Centerforce II but they call it the Dual Friction. Is one better than the other?
The cost is almost the same.


These are 11" clutches, they also list 10.5"

There is also a DFX kit that I assume is for higher HP.

 

If your car is a street driven cruiser, go with a CenterForce I.


If you have power modifications, go with the CenterForce II.


I ran the II version for years - light pedal, good hook up, and very reliable.


Suggest that you use the pilot bearing, BCA7109.

 

Thanks Paul,


I called Centerforce and they recommended the Centerforce I as well. It's good to 500HP which is way over what I have. The kit at Summit Racing is cheaper than buying the pressure plate, disc, and throwout bearing separately directly from Centerforce. Hopefully the throwout bearing that comes with the kit isn't a POS. I don't need an alignment tool and I'll throw the bushing away and buy the BCA7109

 

The centerforce dual friction was highly recommended by a good friend, a fellow Aerospace Engineer who runs one in street/strip mustang. So, that's what I'm running behind my 455. No regrets. This design uses counter weights on the diaphragm that increases pressure on the disc as rpm increases. This allows relatively light feel to the clutch pedal. The design is patented so no one else can copy it. To

 

Is there any reason I can't run a 10.5" instead of an 11"? For whatever reason I ordered the 10.5" and didn't realize it until the pressure plates holes weren't lining up with the old ones. I ended up installing the 10.5" but now I'm having second thoughts. I haven't bolted everything else up yet, just the clutch and pressure plate are in place.


The pressure plate only gets torqued to 17 ft.lbs according to the Factory Service Manual that and that seems really low. Does anyone else use Loctite and I assume you use lock washers.