Does anyone on the list with a higher performance engine know anything about or have experience and opinions with solid vs. springed clutch discs? Thanks.
Original Post
Replies sorted oldest to newest
Does anyone on the list with a higher performance engine know anything about or have experience and opinions with solid vs. springed clutch discs? Thanks.
David, I use the 210mm Bus clutch disc between the Type IV and the '63 swing-axle case.
It has four springs in it, and does me fine.
It has four springs in it, and does me fine.
David,
On a street car, always go with a marcel (aka spring) clutch. The springs take the shock of the stop/start and save the rest of the drive train. Much more pleasant to drive as well, but there's actually a mechanical reason to stay with marcels on the street.
I've driven solid discs on the street (a dual disc full race clutch). I got used to it and it is certainly do-able, but in hindsight, I would not have done it again.
angela
On a street car, always go with a marcel (aka spring) clutch. The springs take the shock of the stop/start and save the rest of the drive train. Much more pleasant to drive as well, but there's actually a mechanical reason to stay with marcels on the street.
I've driven solid discs on the street (a dual disc full race clutch). I got used to it and it is certainly do-able, but in hindsight, I would not have done it again.
angela
David:
I'm running a so-called "spring" clutch disk on Pearl. The springs are there in some stock and most higher-performance clutch disks to act as an absorber to make a performance clutch more street-able. Performance clutches are notorious for being "binary", meaning that they either fully grab or fully disengage. Power comes on....WHAM! when they're engaged. With a spring disk, there are actually two, floating parts with the springs engaging both plates. When the disk is engaged, it kind-of slips in (it engages very quickly, but not instantaneously) and thereby absorbs some of the shock to the drivetrain (and you), reduces clutch chatter and so forth (much like the chatter from a mis-adjusted Bowden tube). Spring hubs also absorb some of the chatter from harmonic stresses of the crankshaft (which can be prominent if you're running a very light flywheel (under 10 lbs.) and no harmonic balancer pulley on the other end.
Better spring hubs have really beefy spring retainers, as the #1 cause of spring hub failures is the springs loosening up and falling out (DUH!) and doing all sorts of mischief whilst flying about in there.
If you're running a hi-po engine AND expect to do HD launches off the line a lot, a spring hub is the ticket for you.
hmmmmmm.......I see that Angela just said the same thing with a lot less words.
I'm running a so-called "spring" clutch disk on Pearl. The springs are there in some stock and most higher-performance clutch disks to act as an absorber to make a performance clutch more street-able. Performance clutches are notorious for being "binary", meaning that they either fully grab or fully disengage. Power comes on....WHAM! when they're engaged. With a spring disk, there are actually two, floating parts with the springs engaging both plates. When the disk is engaged, it kind-of slips in (it engages very quickly, but not instantaneously) and thereby absorbs some of the shock to the drivetrain (and you), reduces clutch chatter and so forth (much like the chatter from a mis-adjusted Bowden tube). Spring hubs also absorb some of the chatter from harmonic stresses of the crankshaft (which can be prominent if you're running a very light flywheel (under 10 lbs.) and no harmonic balancer pulley on the other end.
Better spring hubs have really beefy spring retainers, as the #1 cause of spring hub failures is the springs loosening up and falling out (DUH!) and doing all sorts of mischief whilst flying about in there.
If you're running a hi-po engine AND expect to do HD launches off the line a lot, a spring hub is the ticket for you.
hmmmmmm.......I see that Angela just said the same thing with a lot less words.
to make it last a clutch is either engaged or disengaged not slipped so when you let it out and it just starts to grap dump it dont ride it and it will last a lomg time. bill
Thanks for the quick reply, people. I do have a massive chatter problem with the clutch package Kennedy sent me. I don't do hard launches. Interestingly, their website notes that for comparison to their torque rated clutch packages, the stock VW 200 mm clutch can handle 134 ft.lbs. of torque. My Soob engine is rated at 137 but I doubt it could supply that much due to the carb install ( I tossed the fuel injection system and also have a non stock but fairly free flowing exhaust) so the VW stock package might have just worked anyway. The stage 1 clutch pagkage I bought will withstand 180 ft. lbs. However, and just to clarify, the Kennedy disc is a Marcel style having the wavy washer type part between the disc surfaces. It doesn't have any springs in the hub area though. For comparison, my stock VW disc has six smallish springs in the hub and a double Marcel between the surfaces. Maybe sticking a high quality VW disc in with the Kennedy pressure plate might be a good combination. I'm aware that there can be many causes of clutch chatter. My tranny mounts are good and there's a fair dip in the bowden tube. I've changed nothing other than the engine and Kennedy's clutch package.
We'll see what Kennedy says tomorrow.
We'll see what Kennedy says tomorrow.
David,
My clutch is the 215mm stage 2, for 270 horse from Kennedy. There is no chatter. It is the marcel type - the marcel is a spring, just not a coil type like you see on the typical clutch disc. Think of it as a wave spring.
If you have alot of chatter, you have something wrong - sorry... This setup should not chatter either under normal use or under aggressive use.
angela
My clutch is the 215mm stage 2, for 270 horse from Kennedy. There is no chatter. It is the marcel type - the marcel is a spring, just not a coil type like you see on the typical clutch disc. Think of it as a wave spring.
If you have alot of chatter, you have something wrong - sorry... This setup should not chatter either under normal use or under aggressive use.
angela