So, I fitted a BMC CDA to my 156. Not because I'm a boy racer
but because she'd been stuttering at low revs when pulling away and I'd noticed that cleaning the throttle body had improved things so I wondered whether she was suffering from poor mixture/air throughput etc. I'm no mechanic but I like to spend time tinkering with my bella.
The outcome after fitting the CDA is a marked improvement. I'm not saying it's fixed the problem completely but there is a significant improvement.
What's more, I've also noticed that my fuel consumption has improved slightly - instead of 430 miles to a tank the last two trips to Doncaster and back (a regular trip every week) I got 460 and 475 respectively. And there's more - she seems to be using slightly less oil. Over 1000 miles, I used to have to top the engine oil up from around the half way mark on the dip stick, whereas this time it was roughly 3/4 way up the dip stick after 1000 miles. Early days I know, and I accept that my 'measurements' are not an exact science but could there be a technical reason for the fuel economy and less oil usage?
Up shot is, I quite like the occasional grunt the CDA gives, driven normally round town you'd never notice it is there, but give her some welly and there's a definite low end growl. Cant say the performance is greatly improved though - but that's fine - that's not what I was after.
Fitting the CDA was pretty much a doddle. Secret is to remove the battery and tray for easy access from above. One question though - I've seen several pictures of the JTS with a CDA fitted where the MAF is moved from the air box end of the induction tube, and re-located next to the throttle body intake. I've tried it in both locations and I can find no difference in performance, other than when it's located next to the throttle body the revs rise to 1500 for 10-15 seconds and then drop down to the normal 1000, whereas when located on the CDA end it starts up and sits at 1000. This is only from cold though, From hot she sits at 1000 when started regardless of where the MAF is located.
I've kept the original induction parts just in case though. I never know - if I ever sell her the new owner may not be to chuffed with the CDA