I had a chance to talk with David Lickfold, a phone call that Marqie very kindly arranged for me. Honestly, I felt bad taking up his time. David's time I'm certain is valuable, so I'm very grateful that someone at Lucid, let alone David, is taking time out of his day to speak with me directly.
David asked me how the Gravity has been for me so far, and while I think this might have been an open ended leading question to my brake complaint, I instinctively complained about my second row seat squeak. Half way through complaining, I realized in my head I was wasting the David's time by talking about something that wasn't in his wheelhouse. I quickly pivoted to the brakes, as that was the real reason for the call.
What follows is just an interpretation of what I think David was trying to figure out.
I described to him my issue with the brake pedal. On high regen, when the Gravity is under full regen deceleration, if a car in front of me suddenly increases its rate of deceleration and I am required to apply a brake input. I feel the brake input required to increase the rate of deceleration requires too much pedal input. It throws alarm bells of in my head.
David started by asking me if I felt that the force required or the input distance was too much. I replied that I feel that travel distance of the pedal is too much. Essentially I think David was thinking about brake pressure vs brake pedal stroke. While I would prefer a stiffer pedal overall in the Gravity this is just a preference characteristic. I hate the feeling of an over-boosted brake pedal, its too soft and gives no feedback.
Then David ask if the Gravity was my daily driver, and if I drove any other cars in rotation with my Gravity. I suspect he was trying to determine if I was more accustomed to a different braking system feel because of constantly switching from one car to another. Fortunately the Gravity has been my only car I have been driving in the last 6 months. I used to commute almost exclusively by bike, as some of you may remember. However, I did tell David that I have had a lot of seat time in two cars: 2007 Cayman S and 2015 Subaru WRX. My Cayman was autox dedicated car, and the Subaru a dedicated track car. I mentioned to David that the Subaru was using a 6 pot Essex AP Racing BBK. He acknowledged I was an enthusiast, and hopefully this gave him some perspective from which I was assessing the Gravity's braking feel.
David then suggested we bring my Gravity into a service center for inspection. That he would have an engineer there to be with the technicians as they inspected the braking system. He made the point was that braking is subject, but before anything qualitative could be taken into consideration that they must quantitatively insure that the braking system of the car is performing to the specifications set forth by Lucid. Essentially, my complaint might easily be explained by a braking system that was not functioning as designed or out of spec. He didn't really elaborate what would happen if the system was determined to be in spec, but I assume my observations would just be taken into consideration for any future brake tweaks done via OTAs or model refreshes; assuming they fielded similar complaints.
I took the opportunity to take my complaint and ask David if they have ever felt this way about the Gravity's braking system. IE Has him or any engineer felt that under the same brake scenario felt that the brake pedal required too much pedal stroke. He said we are all different, and our perception of the brakes are all different because of our individual sensitivity and experiences, and that they also test several different iterations of the Gravity during development so its very hard to answer the question.
We concluded the call, and our next step is to bring my Gravity in for service and inspection.
When I sit back, and think about the problem, I don't dismiss the fact that the braking system might need a bleed or is function out of spec. However, I keep coming back to the challenge of the moment you apply brakes when the car is under regn. It must be a challenge to blend these two system. For one, there are two regen modes, standard and high. Both of which produce two different rates of deceleration or curves . Then I think of the brakes themselves, and how if you only stopped the car via the physical calipers it has its own stopping characteristics or curves. Forgive me if this is the incorrect way of thinking about this but I imagine when you first release the accelerator, the regen curve begins, and it follows a defined shape set by Lucid depending on whether you are in standard or high. However, along this curve, if you apply the physical brakes, then there must be a transition or inflection point in the curve and this point of change must be well blended. And realistically if you are in regen and apply the brakes, you would imagine the curve would steepen in slope because the driver is requesting additional deceleration than what regen is providing.
The challenge here is that the brake pad compound is fixed, so how do you blend the physical braking curve characteristic to two different regen curves?
I suspect if I drove around with the standard regen I might not have this complaint of the braking system. And perhaps the compound of the physical brakes are better "tuned" to the standard regen curve than the high regen curve. Thinking of my curve analogy, what I think I am feeling is a dip in the slope of the curve at the point where I apply the physical brakes, relative to brake stroke, in high regen mode. And to get the slope to steepen, I am required to input more pedal stroke that I'm accustomed to.
Assuming all the above is true, and not just me pulling stuff outta my ass. I guess this scenario makes sense, because how can you get two different physical pad curve characteristics from the same exact pad compound when applying the same pedal stroke? Maybe this solution is the best, and I'm being particular sensitive.