4,500km in and I said I’d work on an update, prompted by an unsatisfactory drive on Sunday night. So make a cuppa before starting into my meandering thoughts!
The previous 4,000km had been 100% office-bound commute stuff – 48km/h avg speed, deep floods, manky rain, in the dark, pressure at work etc etc… no motoring joy was had at all. To compound it, I’d been sick the previous week and cabin fever reached a pitch as my wife had gone to a spa for the day. So Sunday night came and I said I’d take the long way for a litre of milk & some bread.
What a joyless experience – caught behind traffic for alot of my local route, including the best bit being ruining by having a garda Mondeo in front doing 20km/h below the posted limit and stabbing brakes randomly. And on the bits I did get clear road for I found the car not flowing at all, with two stabs at the wheel, turbo lag, jumpy downshifts, running out of gears too quick ... my own inputs just not getting the car flowing basically. I came home with milk, bread, and a Galaxy bar as comfort food for the let down.
So Monday I’d to go to Kerry for some work. The previous night was fresh in my mind so I decided I’d take the marginally longer, but infinitely more satisfying, route and concentrate on driving the MPS with a bit of brio – something I hadn’t actually done since my drive home in October. I hit for the hills…..
There is definitely different driving techniques required for these turbos, isn’t there? Most of it is me, some of it is MPS-related, but some I am guessing is generic 4x4 turbo. So I’ll go through how I was dissecting my drive, as I think it is of general benefit. And please Scooby & Evo owners I’d love to hear your experiences and thoughts on my general observations too.
Steering
When you up the pace and input, the Mazdas steering wheel is a very sharp device to use, despite 2.6 turns lock-to-lock. I noticed I was putting in too much elbow, and as a consequence the car was darting into the bend and requiring a slight wind off of lock & invariably a re-application again. The 2 stabs meant the corner was a bit messy before you even really began, but it did teach me that there is a lot of front end grip in the MPS. In fact, unless you were flat out mid-bend under power, I don’t think you would sanely discover what would make this car understeer on a public road. I’m still trying to figure out how I was making this over-input mistake, as I’ve jumped between 5 series & Elise for the last 3yrs no problem, have done 4k in the Mazda smoothly whilst pottering, and it is such a basic component of driving. I think the nature of the power delivery made me subconsciously drive more aggressively with steering, brakes & throttle or something, but there you go. Lesson #1: The car needs measured and accurate inputs to get the most from it.
Throttle
Turbo Lag is thy enemy to a nice flow. I found myself having to slightly modify how to heel & toe, specifically the timing & amount, to suit the engines characteristics. This was a slightly fluid problem, but I’ll come back to this point further down. I also found I’d to concentrate much more on upshifts. Turbos go BWARP-shift-pause-BWARP, and there is a lot of fun to be had banging through changes flat out if you’re into it, but I’m not. No problem when you’re schmoozing, ignorable if a person was into V-maxing, but kind of frustrating when you are making ‘safe but efficient progress’© which I like to do. So I had to speed the shift up a tad, soften the lift on change and reapply earlier to smooth this out – it doesn’t remove the problem but does enough for it not to be a problem, and matches road to engine speed better. It also speeds up the gearchange & the box feels happier. Lesson #2: Feel what the car is telling you; it’s trying to make you drive it better
Cornering
So many elements here, but I’ll keep it concise. RWD has given me a slow-in, fast-out approach, thereby taking the rear axle on in my own terms, rather than hoping there’s enough grip there for power transfer & cornering. Bends don’t suit the MPs as much if you take them in that style as you’re somewhat back to jerkiness. So after taking the steering and throttle characteristics into account, I found myself braking earlier, and getting on a steadier throttle into & through to apex. 4x4 means you have more confidence in doing this as you’re not going to be grappling with a rear that might go out. And the car is pretty immune to bumps, lumps, & cambers mid-bend (if not under braking), as well as having an aversion to understeer unless you’re mongo on the power. Plus you have the throttle well hooked up so there’s minimal lag.
Lesson #3: You’re not a driving god, there’s always more to learn if you pay attention. And ignore the cars apparent encouragement to be an aggressive 4wd-turbo-nutter-barstward – smoother is better.
Technology
I mentioned heeling & toeing, & how it was a movable problem. I need to do some technical digging on this to understand exactly what the parameters are for this stuff in the MPS, but my thinking is based on the fuzzy logic in modern cars – you know where the auto box monitors driving style and if you’re light on the throttle it’ll upshift early, drive fast and it’ll hold on to gears and downchange more aggressively etc. I’ve been driving like a nanny in it for quite a while, and I definitely think it has had an impact on throttle response and drivetrain. The throttle was much softer and less inclined to go full-lepton if you floored it – measurable only in length of movement and a second or so more between instruction and response, but never the less there. So did I get into the groove yesterday, or did the car get into the groove?
Similarly, there is a water-cooled transfer unit and electronic torque coupling before the rear differential, with 3 set programs (normal, stability, sport) it moves between automatically, depending on a whole raft of inputs: speed, revs, gear, throttle, steering & handbrake position, stability control, abs, brake pedal position & fluid pressure, coupling torque requests, yaw rate, lateral g, & rear LSD oil temperature. It goes from 100F:0R to 50F:50R with a rearward input in most situations. However, I’ve noticed it has been slower to put power to the rear, so on a junction take-off on my commute I was noticing some front wheel slip on gravel where there was none before. Again, just a second of slip, but enough to make me notice. So had the car decided it was in Driving Miss Daisy mode, softened throttle response, and reduced rear torque for less drivetrain losses (mpg did improve slightly for a tank)? I need to do a bit of digging on this, and also what parameters the torque coupling works within for each of its programs. It isn’t allowing any front wheel slip today
The technology in these cars is a bit dizzying, and as someone who tries to pay attention to what the car is doing, the bits and pieces going on are hard to assimilate at times! For example into one bumpy braking area that had a small diagonal rise and fall (<1ft) across the road, I felt a little ABS kick of sorts, but the pedal raised up a good inch underfoot, and I saw the DSC light flash just for a moment. I couldn’t figure it out as I didn’t feel I was braking hard enough to activate ABS, or getting the car loaded up enough to warrant a DSC intervention. Turns out it has BAC – brake assist control – that monitors inputs from the car and assists braking by building additional pressure using the ABS pump. So the pedal feeling wasn’t modulating a wheel lock-up, but boosting pressure. What the DSC light was doing I’m not sure – perhaps as it controls braking on individual wheels it needs to compensate for a moment for the differential brake pressure across the 4, or maybe the BAC control is ran through the DSC sensors and control module? Another one to fathom.
I’d really like to bring it onto a wet circuit where all the systems can be explored thoroughly and knowledge gained of how they react to inputs, rather than snapshots of them through the handful of corners safe to explore the car on. And after a session I’d imagine DSC would be left ‘Off’, so I can understand how the 4wd and active coupling works, not to mention its balance under brakes. That will all have to wait until the 1yr Mazda warranty runs out though of course!
Cars – don’t you just love getting to know them? I wish I could change them every 6 months and keep learning.
PS my lessons turned out to be more relevant to my own driving than any discovery on 4wd turbo dynamics! Which is good too.
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