Some of you may have read my purchase & initial impressions on my Mazda 6
MPS in October
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.
No comments:
Post a Comment