I did a CDV delete yesterday and wanted share my opinion…
Despite owning 4 different manual transmission cars for a total of over 12 years I immediately had trouble executing a smooth shift in my 335 in the lower gears.
After a few hundred miles I learned to shift the 335 smooth by delaying the lift of my foot off the throttle. Problem is that I had to make a conscious effort to do this or I’d go right back to my old timing.
After reading about the CDV delete I had to try it, and let me tell you it instantly made a difference. I’m not an automotive engineer, but my theory is without the CDV restriction the clutch can now reengage before the flywheel slows down too much…making the revs match just right. (Otherwise you would have to think that a slow clutch engagement would be smoother)
Now I don’t have to give shifting a second thought it’s just snick-snick every time!
I highly recommend this mod for anyone experiencing the same shift timing problems that I did. (And who can tolerate the risk of the extra wear and tear on the driveline).