Cars - Manual Transmissions & Clutch Delay Valves

I like driving cars with manual transmissions. My last 3 cars have had manual transmissions. For the most part a car with a manual transmission is cheaper to buy, often gets better fuel economy, and is a little peppier than the same car with an automatic.

But the real reason I like manual transmissions is driver involvement. I enjoy driving. Most people my age, however, seem to view it as a burdensome and expensive way to get from point A to point B. But with the right car, the right road, and the right conditions, driving for me is a great pastime full of challenges and rewards. Steering is carried out not only with the steering wheel, but also involves the careful use of the right foot. Deceleration is not a simple matter of pressing on the brake pedal, but also involves downshifting to the correct gear.

After one has driven a manual transmission for enough time, driving an automatic seems like driving bumper cars at the carnival, or a Power Wheels toy car. No apex, no matter how expertly negotiated, is ever as rewarding in an automatic as it is in a manual. There's just something special about using all four limbs to make a car go.

All that being said, there are a few things that can spoil a manual transmission. My last car, a Miata, had a bad clutch. It had an overly hard friction material that caused a shudder during shifts at low RPMs. After about 10 hours of hard labor, I managed to replace the clutch and the problem was gone.

My current car, a 3 series BMW, came with something called a "Clutch Delay Valve" or CDV.

This is about $0.75 worth of plastic that sits in the hydraulic line between the clutch pedal and the transmission. The job of the CDV is to slightly delay the engagement of the clutch pressure plate, ensuring that an unpracticed driver doesn't inflict undue stress on the drivetrain of the vehicle. Evidently the Germans don't think Americans know how to drive manual transmissions, as the European cars are not equipped with this valve.

Anyway, this valve only serves to frustrate those of us who know how to drive a manual. It causes the clutch pedal to feel vague and disconnected from the transmission. It makes it difficult to identify the actual point of engagement. And of particular concern to me, it causes a rather awkward 1-2 upshift.

Fortunately it is much easier to remove this valve than it was to replace the clutch in the Miata. Took the car for a quick drive and the difference was immediately noticeable.