tangierc

First off, I praise this site. It has educated me so much about the Rx-8, rotaries, tuning, etc. Everyday I learn something new. Though I plan to to purchase an RX-8, I am not quite ready and I tend to research a car first (it's technial problems and owner's responses mostly) before purchasing - particularly when I've never owned a rotary. My point being - with all that I've read on this site about missing horsepower and other quality issues, I want to know if any of you can suggest a number or email to contact Mazda and possibly get a response to some of these issues - straight from the horses mouth. At some point I won't be checking this site everyday and I don't want to miss when Mazda serves up an answer to some of these issues. At the same time I want to speak to someone who can actually tell me something instead of the "contact us" numbers and email's addresses Mazda presents which may never get me any answers.

BillK

Dream on.

5Gen_Prelude

Now why didn't any of you think of that? It's so simple!

rotarymotory

Someone talk more about this. For some of us the RX-8 is a totally new experience. And I owned an RX-7 Turbo about 12 years ago. But there seems to be very little hard information available. I have lots of questions and would like to find answers without having to quit my day job.

-Someone spoke of "cold shutdown procedure". What the...? This isn't a turbo. The manual is weak on hard facts. It's basically good for installing infant care seats, but bad for filling in the new owner that would like to know something about their new purchase.

-Is there a warm-up procedure?

-What is "resonance supercharging"? I've owned 23 cars and have never heard that one before.

-How can I find more about the intake valve workings. (I've already read Road&Tracks guide to the car, but it just whet my appetite.

-What's with the Dynamic Stability Control? It seems slow to react. I've driven several traction control and stability control systems(from GM's to M-B's) and none were this slow to respond. In a real pinch it seems like it would be too late to help.

-This car is great. The technology is amazing. Why is the manufacturer so mute?

-I've heard that the car aced the safety tests. Is that true? Where can I find the data? And as I live in a city where people park by feel, what is the 5mph crash data?

Let's go guys. This shouldn't be hard.
MM

RotorMotor

It's not, but the search button at the top of your screen is even easier....

eccles

Without wanting to take this thread off on a tangent, I actually like the fact that the DSC allows me to have a little fun before the "hand of God" comes down to intervene. If it was more intrusive, I'd keep it turned off.

Tamas

iTrader: (1)

I'm not 100% sure if this means the same thing in case of the RX-8, but I suspect this talks about the feature that changes the air intake route of the engine by opening or closing certain valves, depending on RPMs. This creates varying resonance and the effect will kinda 'ram' more air into the motor due to this resonance.
This is similar to what my current car's engine does. It is a '94 Probe GT and has a V6 Mazda engine (same as in the MX-6), with the so-called VRIS (Variable Resonance Intake System). It consists of two valves that open or close at certain RPMs, controlled by solenoids. It really does work well on a naturally aspirated car and gives you a very noticeable kick in the pants at about 3250 and 5500 RPM. The effect is a little bit similar to the one when turbos are kicking in. Of course it's not THAT strong, but it's still nice.

Sputnik

Do a search, we have checked, and have basically gotten "we'll look into it" types of responses.

---jps

j9fd3s

1. air has mass, when a port opens the air moves to go into the port, it has mass and velocity; or inertia. the port closes the air hits the closed port and bounces back. since the 2 rotor rotary has everything 180degrees from each other, when one port closes the other is opening, so they let the air from the closeing port bounce right into the opening port.

2. i dunno, its the way they have always been. they won lemans in 91, being the first japanese carmaker to do so, and the first non piston engine, but did they bother telling anyone? have you seen more 93-95 rx7's in credit card ads than mazda ads? i dont realyl understand that either

3. this is the same test the ford crown victoria can pass but still manage to burst into flame when hit from the rear?

mike

pelucidor

In one section of the owners manual it says start the car and drive off immeditely (to save fuel). In another section it says wait 10secs after starting the car before moving off. I wait at least 10 secs. before moving and don't use full-throttle until temp is stable.

graphicguy

After having ordered my RX8, I was invited to one of the Mazda tours in my area.

It was hosted by Mazda reps and the training they did was an off-shoot of the training the Mazda dealers get.

I can't answer all of the questions, but I can address some of them as they were told to me by the Mazda reps.

--the build quality, paint, controls, ergonomics benchark was Lexus
--the suspension benchmark was BMW M3
--internal safety tests were done to make certain that the RX8 would fare at the top of the class, of any car regardless of the test
--Mazda reps knew nothing of missing HP nor of any A/C deficiencies
--Mazda reps were aware of the "check engine" light issue and ordered all dealerships to just replace the EVAP module for anyone with a "check engine" failure
--MPG is supposed to get better and better as the car breaks-in
--the stability control unit was purposely programmed not to come on immediately as they felt that would be too intrusive while driving the car as intended...."aggressively" (their word, not mine).

That's all I can remember.

OrangeBingo

Every time the intake valve closes it does so with such force that it creates a pressure pulse that travels back through the intake and into open air. When this pulse reaches the end of the intake system it leaves behind it a vacuum. The outside air (being under atmospheric pressure) rushes back through the intake at roughly the speed of sound (varies somewhat based on air temp, altitude, etc.). The challenge is to time things so that this rush of air hits the intake valve exactly as it is opening. This can be done with variable valve timing and/or variable intake paths. While most systems make do with a single switch over (e.g. Shorter intake for lower rpm switches to a longer intake higher in the rev range) which works perfectly at a certain rpm and loses effectiveness as the rpms change, BMW has the best current system which can vary the length of the intake across the rev range. These pressure pulses also occur in the exhaust manifold, and certain exhaust systems can be made to have a scavenging effect, essentially sucking exhaust out of the cylinder.

Digisan

News flash, the search engine sucks...

XUrotaryrocket

amen

PS - There aren't any quality issues. I've owned a shitload of Mazdas and the 8 is by far the best built one I have owned. They have all been good cars. The Millenia is the next closest as far as build quality. Every new model will have a couple snafus. The question is do you want to deal with them or wait a year?

dcfc3s

First off, you guys gotta get used to thinking rotary. There are no intake valves .

OK, to answer some questions -

- Cold shutdown procedure. Rotaries HATE being started bone cold in the morning, moved briefly (like backed out of the garage real quick) and shut down. This is a good way to flood the engine - probably not so on a nice, factory fresh engine, but try it on a 120,000 mile engine and you'll be sorry . The owner's manual has a pretty good routine - let the car idle for a while, then bring it to 3000 RPM for 10 seconds and shut the car off - some routine like that. Read the manual, it's in there.

- Variable ports and intake tracts. First off, there are what the RX-7 guys call "sixth port actuators". At low RPM, there are 4 intake ports for the engine, and at a higher RPM two additional ports open, for a total of six. This is the equivalent to variable valve timing in the piston engine world. The size, shape, and location of the port in the housing determines how soon it opens, how long it stays open, and when it closes. In a piston engine, the cam dictates when the valve opens, for how long, etc. The two extra ports have sleeves in them that rotate to open - this allows more air in (like the intake valve suddenly got a lot bigger) and also changes the port timing to pull in air longer. Rationale is keep small ports for low-end grunt off the line, then open the extra ports at high RPM to give added airflow and better port timing.

The variable intake tract, if I read it right, is similar to the '89-91 RX-7 non-turbos. There are different intake runner lengths, and this can be swapped between. The sharp opening and closing of the intake ports helps create a pressure wave as the air rushing into the motor suddenly has no place to go (port closed), so it backtracks and helps shove air into the other rotor.

There's also some variability with the airbox - I need to read up on that more, though .


You can "port" a rotary engine - basically cracking the motor open and altering the port size and shape. This is the equivalent to a cam in the piston engine world. There's a street port, which has a good idle and reduced low-end power but makes a good bit more power up top, a bridge port, which gives a lumpy idle, bad low end, and lots more power up top. Then there's peripheral porting, which is getting mighty exotic (exhaust and intake ports in the rotor housing) which has horrible idle, zero low end power, but starts making power around 7-8000 RPM and continues as high as you want to wind it. That's race-only, though.

http://www.rotaryengineillustrated.com will help you guys out a lot if you want to learn some more specifics. My buddy Blake, who did that site, actually drove a peripheral ported 1st gen from Oregon to Florida to compete in the $2003 Grassroots Motorsports challenge.

Dale

tangierc

XUrotaryrocket

I have to agree with the quality. If it weren't for my first purchase out of college - a 2000 Protegé ES, I wouldn't really have considered purchasing a Mazda 'cause I loved Hondas too much. I love my car even when I had a couple of problems (which Culver City mazda gladly took care of) I felt and still feel like I have the best car in the class (Corolla, Civic,...). I love the quality of my car which has led me to purchase an RX-8. The only thing I badly wanted (and seems to plague every Mazda for many of the past years as stated in popular car magazines) is more power. Mazda always seems to come up a little short at least for my liking. When I bought my car it would have been perfect it had the Civic SI engine in it. That would have been the only thing I would have changed - the horses baby - the horses.

XUrotaryrocket

amen

j9fd3s

when i worked for the dealership, they had us autox the protege the civic and a crapolla, back to back (also the 626, accord and camry), the protege is night and day better than the other 2 cars, the hondas are downright dangerous, the power steering cavitates (doesnt work) if you move the wheel faster than normal, while the mazda's are easy to drive, and they perform well

mike

5Gen_Prelude

You people need more smilies...