Longevity of WRXs...?

[Monique Y. Mudama]

Sure, beating the hell out of the car at redline RPMs can be very
hard on the car: just listen to it, it even sounds like it's
labouring. But doing it under normal driving conditions where 4K is
a rearely-touched top-end and 2K-3K is the norm?

I think this is the first time anyone's mentioned specific RPM numbers
on this thread. What you're describing is what I do, but I suspect
the folks worried about engine damage are thinking of downshifts that
cause much higher spikes.

 

[Edward Hayes]

Yes; I was thinking of downshifting from the rpm redline.
Professional drag racers make a point to never back off at the end of
a run while in gear. The possibility of major engine damage i.e.
bearings and stretched rods is just too high. Sorry I ruffeled so many
feathers but, having rebuilt many engines from the crankshaft out I
thought I'd share my experience. Ed

 

[BD]

My dealer's staffed with a Subaru master mechanic, and their advice was to feel free to engine brake in normal
driving.

This is most reassuring... I'm the OP of this thread, and am finding
much of the discussion very useful.

In my case, when I do downshift, I basically never spike it above 5k.
Most of the time when I gear down, it maxes out at a little over 4. I
agree that the issue would be a much bigger concern if I were
continually red-lining the motor as I slowed down, but that's far from
what happens with me.

I agree that 'technically', if the motor is used to brake, it will
result in additional wear than if it were not. But I think that if a
driver is not a complete cowboy about it, that kind of driving habit
should not be a real detriment to the car.

 

[k. ote]

This is most reassuring... I'm the OP of this thread, and am finding
much of the discussion very useful.

In my case, when I do downshift, I basically never spike it above 5k.
Most of the time when I gear down, it maxes out at a little over 4. I
agree that the issue would be a much bigger concern if I were
continually red-lining the motor as I slowed down, but that's far from
what happens with me.

I agree that 'technically', if the motor is used to brake, it will
result in additional wear than if it were not. But I think that if a
driver is not a complete cowboy about it, that kind of driving habit
should not be a real detriment to the car.

I don't think it's hard on the engine at all at normal speeds; in terms of
additional wear as in "normal wear you see when the engine is engaged" I
suppose that's correct: but certainly no "undue" wear and tear.
Additionally, if you just use the brake to slow down, then you're most
likely in the wrong gear by the time you stop and in an emergency situation
you are screwed in your reaction times by an additional clutch-shift-clutch
sequence that could mean the difference between life and death.

Therefore, even from a safety standpoint, it seems to me that it's in the
driver's best interest to keep the gears reasonable and downshift properly
when coming to a stop. I'd hate to be doing 15kph in 4th and suddenly see a
semi coming at me full-tilt from the side.

That would suck--especially since I can't actually downshift to 1st until
I'm around 12kph or slower unless I do a full double-clutch (rev-matching
does nothing in that case.) The car just prevents it.

Anyway, good luck with your engine, and I sincerely hope you all have a nice
weekend!

 

[Monique Y. Mudama]

That would suck--especially since I can't actually downshift to 1st
until I'm around 12kph or slower unless I do a full double-clutch
(rev-matching does nothing in that case.) The car just prevents it.

By the way, why is this? It's incredibly annoying in stop and go
traffic, not to mention on certain very steep roads with switchbacks.

And what is this double-clutch maneuver? I know there's such a thing
as a double clutch transmission, but double clutching in a modern car?
What's that?

 

[Ron N.]

By the way, why is this? It's incredibly annoying in stop and go
traffic, not to mention on certain very steep roads with switchbacks.

And what is this double-clutch maneuver? I know there's such a thing
as a double clutch transmission, but double clutching in a modern car?
What's that?

No wonder you don't downshift. It's the way almost all truck drivers
and high performance drivers downshift any manual transmission
smoothly.

Double clutch by letting out the clutch as you shift the transmission
through neutral, then rev match by the difference in gear ratios, then
clutch in and shift into the lower gear. Much less wear and strain on
the tranmission since the gears are spinning at about the same speed
before they're meshed. Then letting out the clutch the second time
causes almost zero clutch wear because there should be almost no
difference in speed between clutch plates. The car won't jerk when you
clutch out the lower gear since you've already used the gas pedal to
bring the engine up the the correct RPM for that gear and your current
speed. You can use the tach to measure whether you've blip'd the RPM's
up by the right amount for your selected lower gear.

Some drivers can do it so fast you can barely see them hit the clutch
pedal twice, but you might be able to hear the blip of the gas pedal
in between clutchings as the shift lever rapidly passes thru neutral.

I hope I have that right, since that's how I've been downshifting my
Toyota for over 300K miles.


IMHO. YMMV.

 

[Blair Baucom]

By the way, why is this? It's incredibly annoying in stop and go
traffic, not to mention on certain very steep roads with switchbacks.

And what is this double-clutch maneuver? I know there's such a thing
as a double clutch transmission, but double clutching in a modern car?
What's that?

Take a look here:

http://en.wikipedia.org/wiki/Double_declutch

Blair

 

[Monique Y. Mudama]

Monique Y. Mudama wrote:

No wonder you don't downshift. It's the way almost all truck
drivers and high performance drivers downshift any manual
transmission smoothly.

Er, I'm not the one who doesn't downshift. But it sounds like I can
learn a thing or two about it, anyway.

 

[Michael Pardee]

My technique has been to hit the throttle (clutch out, in neutral) to ensure
the rpm is somewhat above the speed it will be in the next gear down, then
catch the shift as the gears slow down by maintaining light pressure on the
shifter. Same concept, just the quick and dirty version.

In either case, the technique involves shifting into neutral and letting out
the clutch, using the engine to bring the gears up to speed, then shifting
into the lower gear.

Mike

 

[k. ote]

By the way, why is this? It's incredibly annoying in stop and go
traffic, not to mention on certain very steep roads with switchbacks.

Hrm. I'm not sure. I do know that the STi's gears are pretty tall,
especially for the lower gears. At around those speeds, being in first
requires the engine to rev at around 4,000 rpm. It could be a (slightly
over-)protective measure to ensure that I don't accidentally shift
dangerously into a gear that would push the engine unsafely beyond the
redline.

And what is this double-clutch maneuver? I know there's such a thing
as a double clutch transmission, but double clutching in a modern car?
What's that?

Clutch down, shift to neutral. Clutch up.
Rev engine about 1.5K (or less depending on how fast you are.)
Clutch down, shift to lower gear.
Clutch easy up.

Spins up the gears so the engine mates nicely with the transmission, lessens
wear, doesn't use the clutch as a brake pedal, and in tight cornering it
can help reduce unwanted weight transfer which could mean the difference
between keeping enough grip to finish the corner and sliding.

Course.. I don't travel at those speeds even on the track, but I was told it
was good to get into the habit now.