So even though the mileage is only 21k right now, and was just under 20k when I got it, I noticed the clutch will slip if accelerating briskly in 4th, 5th, and 6th from a steady cruise with rpm's around 3k giving it 1/2-3/4 throttle. I suspect 20k miles of driving in NYC (mostly in Staten Island) contributed to the short life
It's not something that shows up in everyday driving, but can be reproduced. It's easily avoidable, and doesn't really require me to change my driving, but is something I'll need to address.
Reading up on it I've learned how a dual mass flywheel (DMF) works, and why they are used. I'm wondering if there is a reliability benefit if I go to a SMF, and if it will affect drivability for a street driven car?
I also came across this when researching: Sachs Performance clutch and flywheel
Who makes a good SMF for DMF for the R56?
Based on the work involved I'd like the to be a "cry once" project.
02Pilot
PowerDork
8/21/24 3:52 p.m.
Not the same platform, but I switched my 128i from the factory DMF to SMF a couple years ago (trans was out and it seemed like a good idea; the DMF was fine at ~140k miles). I used the Valeo kit from FCP Euro. When it's cold, I find it difficult to shift smoothly, but once it warms up a bit, it's fine. Note that I've also pulled the CDV and have the throttle pedal remapped for more progressive engagement, both of which may be contributory factors to the cold behavior. It's not severe and I'd probably do the same thing again, but the cold behavior was a little bit of a surprise.
I've put plenty of the Valeo clutch assemblies with a solid flywheel in a bunch of R53's, but I don't know if they make one for the R56. All of the ones I've done have been terrific, with no issues and smooth and easy to use. No cold shifting issues. The R53's had a noise from the flywheel (named Chewbaca cause it sounded like him!) but I don't know if the R56 did......that's why we replaced so many DMF with solids ones - it cures the noise as well as gave a better clutch - easier to push and better feel.
If you can find a Valeo for the R56 it will be a good way to go.....
In reply to MiniDave :
The Valeo kit looks interesting, but unfortunately there isn't one for the R56.
How bad of a job will this be? I haven't looked at the service manual, but I noticed there is not much room in the engine bay.
In reply to 02Pilot :
I appreciate hearing about your experience going from DMF to SMF. What is the CDV?
02Pilot
PowerDork
8/21/24 8:01 p.m.
In reply to No Time :
The CDV is the clutch delay valve - basically, a coupling with a small orifice that limits the flow of brake fluid to the slave cylinder. It's sort of training wheels for the clutch.
In reply to 02Pilot :
I can see why you want to remove it, since it sounds like it would cause more annoyance than solving any issues for an experienced driver
I'm guessing you and I both learned using mechanical or cable clutches where it was all up to the driver to regulate how quickly the clutch was engaged.
02Pilot
PowerDork
8/21/24 8:47 p.m.
In reply to No Time :
Yeah, it's clearly there to mitigate issues with harsh clutch engagement, as is the DMF. They may also serve to limit sudden application of power to the driveline in high horsepower applications, but that's speculation.