BMW M5 Forum and M6 Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
4,515 Posts
Good point, but nobody said that here. Discussions have been focused on practical, proven M5 street clutch options.

Multidisk clutches have been around for perhaps 50+ years in everything from: 1) race cars, 2) go carts, 3) almost all car automatic transmissions, 4) almost all motorcycles. Your Ford F150 pickup with automatic tranny or Mercedes S600 has several of these clutches in the drivetrain. The multiple disk design effectively multiplies torque rating by the disk count, so diameter can be greatly reduced with modest increases in stack height. Dry designs (not immersed in oil) can not absorb much heat from sustained slip. For street, a clutch must be able to be slipped for a minute or more by some moron sitting on a hilly intersection. A good street clutch is also used to carefully, effortly and smoothly modulate power transmission to the wheels. Multidisk dry clutches are more suited for abrupt ON-OFF engagement with only momentary slip. In drag racing applications, the clutch packs are changed every 30 seconds or so of runtime, so figure that into your trip to the mall involving 10 stoplights. You can not just fit a clutch of any size or design into a cramped OEM bell housing designed for a single disk clutch. There are many issues, even if you are trying to substitute a single disk clutch of similar design.

Needless to say, multidisk clutches are not sold for M5 in conventional clutch use. They offer very poor modulation & heat absorption qualities, so they are not suitable for a 4dr street car. A motorcycle or aggressive race/sport car, yes.
 

·
Registered
Joined
·
931 Posts
Also, if you are 'just' compairing size, add up the total surface areas and the 'small' clutch is a lot larger. Interesting picture with Jay :haha2:

LOL
 

·
Registered
Joined
·
2,998 Posts
it's very similar to a motorcylcle clutch.

only bad thing about it is carrera gt owners have been saying it's hard to launch the car cuz it revs so **** fast....which is why i favor the smg/f1 paddle style trans for the reallly fast cars or hey a nice auto :)
 
1 - 7 of 7 Posts
Top