Testimonial - F20 M140i - B-Series Sport Suspension - Mr Luwalira
How are you? Thanks for checking in. Yes I grant your permission to use photos of my car on social media as long as the registration plate is blurred or drawn over.
Would you also mind emailing me the receipt as I have lost the physical copy.
The suspension has surpassed my expectations. My car has been transformed from a fun all-rounder to an engaging sportscar with improved ride comfort.
I bought the M140i because I wanted performance car that is fun to drive but comfortable to clock miles in on my local b-roads that are terribly broke. Because of the firmness of the passive suspension I specced adaptive suspension by default. From factory it was a comfortable car that met the brief as a brilliant daily driver.
However a few weeks into ownership I came to the realisation that the car is not great for enthusiastic driving. Constantly flicking between the comfort and sport settings, I was never 100% happy with the ride.
The comfort setting wasn't engaging enough while the sport setting is too form for UK roads. On bad roads, the bounciness(pogo effect) of the sport setting resulted in headaches from my head bouncing off the headrest. It was glaring that the car wasn't good at following the road surface. As a result I had low confidence in the car. Basically the suspension was underperforming.
The Birds B1 Suspension and the OEM underbody brace that was fitted at the same time have transformed the M140i into a world class piece of machinery. It's now a sorted car like a 911 Carrera S, Supra mk5 or MX5.
My biggest surprise is the increased driving emotion. Because there are no adaptive dampers to cancel out yaw and pitch, my lower spine feels more connected with how the car moves through the landscape. Although body roll has been reduced there is still some but it progressive and less loose. The way the car drives is still in keeping with the spirit of the M140i. I did not want a suspension that was aiming to make the car drive as flat and firm as a Caterham.
One aspect I was unwilling go compromise on when changing the suspension was comfort. At low speeds the penalty over adaptive suspension is minimal. Above 30mph Birds is head and shoulders superior whether on the motorway or broken B roads. In fact, the ride is so composed and smooth that I have increased speed blindness!
Over deep potholes or big bumps the suspension settles almost immediately on impact rather than unsettle the car and pogo for a second after impact. As a result I have 100% confidence in the car and can carry 20mph more speed on B roads.
When driving alone other half grabs the keys more often to my M140i than her X3 with adaptive suspension. That is a testament that the Birds B1 kit has not compromised ride quality. I am now convinced that a well tuned passive suspension with progressive springs can be better than adaptive suspension.