View Single Post
      04-06-2021, 07:10 AM   #112
bitcore
Second Lieutenant
bitcore's Avatar
108
Rep
216
Posts

Drives: F87 BSM Manual M2 Comp
Join Date: Jun 2009
Location: Charlotte, NC

iTrader: (0)

The jerkey-ness I speak of is not when you clutch down and heads move forward from lack of acceleration. That's expected, of course. What I speak of is a difficult engagement where the car judders or engages harder than expected when leaving from stopped and sometimes the next 1-2 shift. The CDV makes this much more difficult and unpleasant than it needs to be because the delay in your inputs to the action of the clutch. The CDV makes the clutch move in a sluggish and soggy way, but you don't feel this in the pedal. You gain finer control over the clutch by removing this hydraulic restriction. This has nothing to do with the actual shifter and selecting gears.

Mileage has no effect, it's a hydraulic restriction that exists from mile 1. Though, the clutches are self adjusting, I believe, so that's not helping you feel the engagement point through the pedal. As it wears, the engagement point adjusts slightly, automatically. So not only is the engagement point depending on how rapidly you are moving the clutch, but also how recently the self adjustment ratcheting action has occurred. Removing the CDV aids in the feel and finer control over it's engagement. The engagement is no longer DELAYED from what you are expecting it to do.

Think of it as removing the turbo lag, but for your clutch pedal. Another way to think of it is the difference in the electronically controlled throttle on a standard BMW N54 motor, and the N54 in the 1M. The 1M has no throttle delay mapping, and thusly the throttle response is much more crisp and lively compared to a standard 335 or 135, which have throttle damping tables electronically applied that tuners have discovered and are able to flash into normal ROMs now. (IKM0S ROM on the 1M vs IJE0S or I8A0S on other N54 DMEs)



Some don't feel, notice, or care - that's a totally legitimate comment! But those that do notice - it can be really aggravating. If you don't notice anything wrong or unpleasant about your clutch's action, of course, leave it alone. It's your car, and it's very good as it is from the factory. This mod is for those of us that want that extra 10% of quality.
Appreciate 0