No More Oldsmobiles

I'm using the manual mode in my AT much more these days. One situation always nags at me -- downshifting.

Usually I wait until I'm about in the rev range for a downshift and it seems to match very well -- you don't feel it change much. However, if the revs are too high I get a pronounced engine braking. I know how to drive stick, and at these times I would usually be feathering out the clutch while giving it gas. With the tiptronic, you don't have that option.

So, some questions:
Is there excess wear-and-tear associated with downshifting the tiptronic?
What do you do when you feel engine braking?

Vertigo-1

iTrader: (3)

Hmm...sounds like you're just simply downshifting it. Did you know you can rev match the tiptronic? I've rarely ever engine braked, unless deliberately, after I learned this. Rev matching the tiptronic turns the whole driving experience into something entirely different...none of my friends, even the die hard manual ones, think my RX-8 feels anything like an automatic when I'm flying up and down the gears smoothly and powering through twisties up in the mountains. When I'm at a good stretch doing about 3500 RPMs in 3rd, rev match to about 5000 RPMs, downshift, and BOOM the car starts roaring, well within its powerband and heading for redline. Likewise I have them all holding on for dear life when I head straight for a corner at about 40, downshift and rev match about 2 seconds before turning in, brake, and then power through. Hell if I really wanted to I could even heel toe...the pedals are even spaced right for that. One of the things I really love about rev matching the tiptronic is you can do it very, very last second. You can pretty much downshift practically at the same time as you start braking for tight turns, and it'll all work out. I think I'd royally screw up if I attempted that in a manual.

No More Oldsmobiles

Thank you both for your answers.

I want to get good at shifting this car. Is there any place with more tips/discussion on rev matching the tiptronic? I want to figure out what I'm doing right and what I'm doing wrong.

therm8

You get the hang of it after a few tries. 2 to 1 is tough, because of the difference in ratios, but you can make the shift much smoother without getting a full rev match. All the other downshifts are easier. Just keep trying it until it feels right. I haven't driven any other tiptronic cars much, so I don't know if this is an 8 thing or a tiptronic thing. But, I do it without thinking now.

mazdabob

Basically, you just give it a little gas as you downshift, rather than backing off. It's just a matter of timing and practice.

NomisR

How do you give it more gas while you're downshifting an automatic, it's not like you can double clutch the thing since there's no clutch in the first place, or are you talking about adding more gas during the delay between shifts?

Vertigo-1

iTrader: (3)

Basically you're taking advantage of the delay in the tiptronic shifting. If the thing were able to shift instantaneously like everybody wished it did, you wouldn't even be able to do this. But there's that lag where it disengages the current gear and moves on to the next gear. In that moment, you can freely spin the engine. So simply just downshift, slightly tap the gas pedal, and when the next lower gear engages, it engages while the engine has been revved up...thus avoiding engine braking. It's quite easy to do really. You just have to learn over time just how much gas to give for the smoothest match...just like a manual. If you can double clutch this should be duck soup.

No More Oldsmobiles

^^ Good tips, Vertigo-1 and everyone else. I was noticing much more engine braking when I'm letting off the gas and now I have started giving it a little gas on the downshift. Still working on getting it smooth.

I think my familiarity with MT has actually been working against me with the tiptronic. I was being cautious about engine braking, and I was letting off the gas on downshifts. The tiptronic is a bit counter-intuitive to what you learn with a manual.

Mikelikes2drive

Is that good for your engine? on manuals we double clutch/single clutch cuz its better for your transmission, but do you think the tiptronic is made so that you push on the gas during that second of delay? i dont know, maybe you should ask an expert on trannies and find out if thats good for your car?

i thought those tiptronics were made to withstand the engine braking.

StewC625

A) Mazdas do not have a "Tiptronic" ... that's a registered trademark of Porsche.

B) The electronics in the automatic will keep you from screwing up anything.

Some guy was telling me that the "manumatic" function in his slushbox functionally changed the way the tranny worked - like he had two transmissions - in the "manumatic" mode, it used some sort of clutch mechanism (presumably like the SMG from BMW) and doing "manual" shifts with the auto somehow was actually moving gears around.

I trust y'all know you're just invoking an electronic control that prevents shifting of the auto transmission until you move the lever, right?

therm8

I'm not sure I understand exactly what you're saying. What we're talking about is hitting the lever to downshift, then bumping revs up with the throttle in the time between gears. When the lower gear engages the engine is already at the correct rpm for that gear, so that there is no "jerk" when it engages.

For example, coming up to a corner at 65-70mph in 3rd gear, hit the shifter, blip the throttle, engage 2nd smoothly, brake, throttle out of the turn. Vice, coming up to a corner at 65-70mph in 3rd gear, hit the shifter, squeak the tires as you hit 2nd and the drive train catches up, brake, throttle out of the turn. The former seems to put much less stress on the drive train.

And we're using tiptronic much like people use Kleenex instead of tissue

No More Oldsmobiles

I suppose that's one way of looking at it. Or to rephrase, the automatic transmission does not shift until you move the lever.

Please, let's not have an AT/MT flame war in this thread. I am getting a lot of interesting insights here.

Vertigo-1

iTrader: (3)

The easiest way to do this is to downshift, completely lift your feet off the throttle and then immediately give the gas pedal a bit of a stomp. This is what I do when I'm coming up to typical 90 degree street corners. Downshift, rev match, let the car naturally slow itself down from the engine spinning down combined with braking, and then turn in and power through.

A more advanced rev matching technique that I've been trying to practice lately is to actually keep my foot in the gas, downshift (gear begins disengaging), and while still keeping my foot in the gas, continue to depress the gas pedal in one quick press without lifting my foot off the throttle at all (lower gear engages at this point), and then simply let my foot out just a tiny bit out so that gas is still being applied. Basically, the idea is to keep gas applied at all times throughout this shifting period. This tends to be more necessary at high RPMs (say, 3rd gear at 4000 RPMs, and you want to go into 2nd) because you're much more likely to get engine braking regardless of how well you've rev matched if you let go of the throttle entirely for even an instant.

Now if you can perfect this, you should be able to flow right from 3rd to 2nd and continue the car's motion with barely any hint of engine braking. I'm still having difficulty but I've done it before, and it's just freaking cool when it works. I've found that it's very easy to do at high RPMs, but much harder at lower RPMs. But, most of the time, I'm slowing down for a corner when I need to downshift, so I wouldn't need to apply any gas anyways after the downshift. Thus I usually completely lift my foot off throttle and then do a quick stomp.

Just something for you to mess with.

Vertigo-1

iTrader: (3)

I'll admit, I worry about this all the time. You figure the way you "normally" use an automatic is to just simply let it put itself into overdrive and stay there all day long. I'm not sure what I'm doing to the AT tranny by doing all these 2 -> 3/ 3 -> 2 downshifts, and I do them quite often, especially around town when people hover around 35-36 MPH. If you stay in 3rd and drop below 35 MPH the car starts lugging like crazy. So I drop into 2nd, go above 35 for a bit, shift to 3rd, only to have things slow down again.

I'm pretty certain I'm helping the engine more than hurting when I rev match, as there's very pronounced engine braking when you simply shift down while doing about 3000 RPMs in your current gear. But, for the tranny, who knows.

I know most people that ride with me give me a pretty stunned look when they watch the way I drive...like "wait a minute, this is an automatic right???" Like I'm just not supposed to be doing this.

SFShinka

Using manual mode is not like driving a stick. I used to downshift when driving in manual mode also, until I realized that it actually confuses the ECU and its shift points. Over time, you will get weird shifting hesitation, especially if you're experiencing engine braking when you downshift.

The good news is that there is no reason to downshift under normal driving conditions when using manual mode! The ECU will automatically downshift for you, for example, when you are approaching a stop. All you need to do is keep track of what gear you're in and up-shift as needed (unless you need to downshift for some acceleration). Try it and see--it will take some getting used to at first, especially if you have driven stick in the past, but after awhile it will feel quite natural and you won't even need to think about it.

therm8

I'm not sure you read the entire thread. The whole point is smooth shifting for aggressive driving, which the ecu is incapable of doing at high rpm. You're not going to want to stomp on the gas to get a downshift, while heading to a corner at high speed.

StewC625

Well, the whole "throttle blip" thing when done on a manual is to match revs when the clutch is disengaged to keep from "shocking" the driveline and prematurely wearing the clutch by having the wheels/transmission yank the engine up to the right revs as the clutch is reengaged by the driver.

Because the manumatic shift funciton is simply a signal lever that tells the electronics in the transmission what to do next, and the fact that there is no MECHANICAL connection between the gearbox and the engine - only a fluid connection that tranfers the power from the engine to the drivetrain, it's damn hard to "shock" the drivetrain, and there's no clutch to worry about ... therefore no clutch wear. When you move the lever to signal the shift, I suppose if you want to simultaneously blip the throttle to match revs, you can, but I don't see it doing any real good at all. It's an automatic - totally different animal than a manual.

Now that said, if you've ever driven BMW's SMG (Sequential Manual Gearbox), you'll know that's an entirely different animal. Rather than a torque converter, it uses an electronically-operated clutch, and instead of routing fluds in different directions to affect the shifts (like a slushbox/auto trans does), it has mechanisms in it that phyically move the gears in the same way that your hand does when you move the gear lever. On that one, if you "ask" it for a downshift by hitting the paddles or moving the lever, it disengages the clutch, blips the throttle to rev-match, and let's the clutch back out, all in fractions of a second. Tres cool! Of course that trans about as much as 1/3 of an RX-8, but hey, what price is cool tech, right?

Pretty cool stuff.

So, no knock on the auto trans - you made your choice, but I don't see any point in the rev-matching thing unless it makes you happier. And if it does, then rev-match your *** off, bro!

Stew

oreo

Hey, verry cool thread
I have gotten a lot of information on how the auto trans works, I had no idea.
That said, beeing the RX-8 a car designed for driver-feel I think that it's all about what makes you feel more comfortable while driving the car. It might work the same braking without down shifting the trans. But if it makes you feel more in control it will make you much more connected to the car. I dont Know how the manumatic function on the rx8 but on mi wifes santa fe the transmision shifts down with speed when the engine is WELL OUT OF THE POWER BAND which means that for spirited driving the automatic dounshifting function is completley useless. If the 8's worksthe same then you will have to downshift manually. In that case rev matching makes a lot of sence, especially since you want to ge able to apply full power on corner exit. If the car is out of the power band you know that will be imposible.

As for the wear and tear of the transmision. All spirited driving (downshifting or not) puts more stress on all components on your car. This just means that those of us who drive the 8 like we stole it will have to be that much more **** about maintenance. the fluids that Mazda puts on our cars from the factory usually are top notch. So if you are going to replace them (which some people say that you dont have to for tranny but I believe that if you are driving hard you will sooner or later) replace them with high cuallity synthetic ones. Saving a couple of bucks on tranny fluid can ruin your transmission if you drive it hard. Also most dealers use the cheap stuff so dont trust them to put the good stuff on your car unless you give them the product.

No More Oldsmobiles

I'm not all that happy with the automatic downshifting it does in manumatic mode. When slowing down in third gear, it seems like it won't kick down until I'm going about 7 mph or slower, at which point I would be lugging it if I applied any gas. This happens often when slowing down for traffic just as the light turns green and I don't want to make a full stop to let it downshif into first on its own. Another instance is at toll booths where you have EZPAss -- when you need to slow down but not stop.

I'd like to learn more about that. Is this documented somewhere?

No More Oldsmobiles

Yes, the RX-8 behaves this way, too (see my post above). And I wouldn't say it's a probablem solely with spiritied driving. It happens when I come up to cars stopped at a red light just as it turns green and they begin to move. You have to slow, which means you have to downshift, but it's not going to do it on its own until you are just creeping along.

No More Oldsmobiles

Very informative post, Stew. Thanks.
There is a certain satisfaction in doing it right, but there's more to it than that. A harsh downshift will slow you down, maybe even lean you forward in your seat a tad. I'm not saying it'll throw you forward like a panic stop, but it's not ... elegant.

No More Oldsmobiles

I've been trying the first techique, and it works. When it's second nature to me, I'll mess around with that second technique.

StewC625

Here's a good link:

Auto Trans in "How Stuff Works"