[Nezil]

Originally Posted by XutvJet

About a week ago i decided to swap back in the stock pedal and see if what you were saying is true about the helper springs and bite point with the UCP. I have to say, you are certainly right. I find it a lot easier to modulate the clutch bite point compared to how it is with the UCP. I have the stock pedal working with the UCP clutch stop with the two metal washers removed.

I think in all of the excitement of UCP lowering the resting point of the pedal over stock (my biggest complaint), I must have glossed over the spring/bite point issue.

That was my experience anyway...

I’ve actually gone back to the UCP now, partly because of this thread and wanted to see if my memory was correct, and mostly because as you point out... it’s an expensive part that I don’t want to have resting on the shelf! I think I’m going to stick with it, but I’ve got the spring set to what UCP calls ‘stock’.

My personal opinion is that the spring settings should be called ‘Most aligned with the bite point’, ‘Not aligned and difficult to modulate’, and ‘Very hard to modulate’.

I guess far track use, where you’re not pulling away often, having the spring pull the pedal back quicker and make the pedal feel more switch like might be a benefit. It won’t change the speed at which the clutch engages though because that’s determined by the spring on the flywheel pressure plate (and the CDV if present!).

I really don't like the resting point of the stock pedal being so high or that clutch catches half way through the pedal stroke, but it is certainly easier and smoother for me to drive and less thinking is involved. I can certainly shift faster with the UCP and for harder driving, it's ideal, but perhaps for daily driving, it's not ideal if you value smooth take-offs and shifting. My wallet hates to say it, but I think I'm leaving the stock pedal in.

I actually found that I had to adjust my seat once I’d fitted the UCP because the bite point is effectively lower, so I needed to move the seat forward slightly. I’m used to it again now, but I never found the higher position of the stock pedal to be much of a problem.

Regarding the CDV delete, do you notice the bite point being more consistent? It seems to me like the CDV causes it to move position in the pedal stroke. One thing I've noticed is that you can hold the pedal out just to the point that it's biting and you can actually feel the clutch very slowly engage the gear with absolutely no change in pedal movement. My guess is that's the CDV in action.

Yes, absolutely. The CDV has the biggest impact in terms of clutch modulation.

I think that the clutch paired with our turbocharged engines can be difficult to modulate because the torque is so large and relatively non-linear (rises very rapidly over a short rev range), and the CDV just makes this harder.

One thing that really bugged me when I got my M2 was downshifts. I’ve driven manual cars for the entirety of my driving life (23 years now), and when down shifting, I can confidently rev match... or not, if I’m just driving leisurely. In the M2, with auto rev-match on, you have to use the clutch like a switch, and everything works OK, but with it off, it was damn near impossible to shift smoothly.

Manually rev matching is possible, but slow (because you’ve got to account for the fact that the CDV will slow the point where the clutch engages, by which time your revs will have dropped from where you set them). Trying to down shift while slowing without rev matching was just awful... To do this you’re effectively slipping the clutch slightly as you shift, to match the engine speed to the (slowing) wheels, but the CDV prevents you from being in control of when the clutch bites. You try to let the pedal out at a controlled pace, your brain tells you to keep going because it’s not engaged yet, then suddenly it snaps shut and you get a clonk though the drivetrain... Infuriating!

Once you remove the CDV, all of that is remedied. Do it now... Christmas holidays are the ideal opportunity!