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View Poll Results: Is the Mazda RX8 Good or Bad?
GOOD!!! 17 43.59%
BAD!!! 22 56.41%
Voters: 39. You may not vote on this poll

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      08-28-2007, 09:31 PM   #23
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      08-28-2007, 09:47 PM   #24
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Quote:
Originally Posted by onehots2k View Post
I hope I didnt read this wrong spin. I average 25mpg driving my s2k. I'm barely on the highway too!
s2k, I was referring to the official EPA rating of 20/26, which is already better than the RX-8. But I've also heard that most s2k owners can easily pull the EPA rating, while RX-8 owners struggle to get even that craptacular official rating.

I really wish rotary engine turned out to be better than it is. The simplicity of its concept is very appealing to the geeky side of me. (maybe there is no other side) And I bet if there were more than one company to do R&D on it for the last few decades, a lot of the problems would've been solved by now. But as it stands, the whole world of automobile manufacturers spend money on advancing the technology of reciprocal engines, while rotary gets some fraction of Mazda's R&D. It just can't win.
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      08-29-2007, 07:37 AM   #25
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My friend struggles to get 15-16 in his RX8.

I didn't know the rotor spun at 1/3 the speed of the crankshaft. That's interesting.
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      08-29-2007, 07:52 AM   #26
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The rotary suffers from two problems - apex seals and a moving combustion chamber. They are inherent to the design. I gotta give Mazda big kudos for taking a technology and sticking with it - for awhile (in the late '60s) it appeared that all the major manufacturers were working on rotary offerings (the rights in the US were held by Curtiss ) but none of the big players pulled the trigger on offering them in production cars. Ford had a rotary in a Mustang mule, GM was going to put one in the Chevy Monza (in fact the Monza was designed for the rotary - that's why it was such a pain to change rear plugs on a Monza) and the #1 vehicle intended to receive a rotary that didn't . . . the AMC Pacer.

There are a couple of well written books available on the rotary engine:

Wankel, Nicholas Faith - a history of the engine and it's development by manufacturers

The Wankel Engine, Jan Norbye - very technical review of the engine complete with engineering drawings and, gasp, math ; -)
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      08-29-2007, 08:16 PM   #27
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Quote:
Originally Posted by spinzero View Post
s2k, I was referring to the official EPA rating of 20/26, which is already better than the RX-8. But I've also heard that most s2k owners can easily pull the EPA rating, while RX-8 owners struggle to get even that craptacular official rating.

I really wish rotary engine turned out to be better than it is. The simplicity of its concept is very appealing to the geeky side of me. (maybe there is no other side) And I bet if there were more than one company to do R&D on it for the last few decades, a lot of the problems would've been solved by now. But as it stands, the whole world of automobile manufacturers spend money on advancing the technology of reciprocal engines, while rotary gets some fraction of Mazda's R&D. It just can't win.
I wish the rotary engine was much better too!! I was looking at the RX-8 a few years ago. I'm kinda glad I didnt go through with it. The novelty has worn off for me.
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      08-30-2007, 07:39 AM   #28
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Quote:
Originally Posted by spinzero View Post
I really wish rotary engine turned out to be better than it is. The simplicity of its concept is very appealing to the geeky side of me. (maybe there is no other side) And I bet if there were more than one company to do R&D on it for the last few decades, a lot of the problems would've been solved by now. But as it stands, the whole world of automobile manufacturers spend money on advancing the technology of reciprocal engines, while rotary gets some fraction of Mazda's R&D. It just can't win.
The problem was the research occurred for a production cycle that occurred at the time of the first oil crisis and then the EPA with the first round of pollution controls (and the rotor has to seal itself in it's chamber - it has to have the equivalent of piston rings which are harder to pull off on the rotor).

But - spinzero - you are onto something about more R&D, and since now only Mazda can pull it off, expect to see them pull this one off sometime before too long.

The one thing that allows the N54 engine to have decent fuel economy, fairly high compression and turbocharging is the gasoline direct injection and that could also 'solve' the moving combustion chamber issue (and the partial burn issues) the rotary has.
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      08-30-2007, 07:51 AM   #29
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Direct injection and high compression are absolute wonders to me. They sure make turbo engines less of a compromise.

I appreciate the rotary--my father drove an RX7 for 15 years. It was a nice engine, very smooth, fun to spin up, sounded good. Mileage was pretty poor, and it burned some oil between changes, but it was very reliable for him. I hope they continue down the path of the rotary, but I still would like to see it in the Miata.
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      10-05-2007, 04:08 PM   #30
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Quote:
Originally Posted by atr_hugo View Post
The one thing that allows the N54 engine to have decent fuel economy, fairly high compression and turbocharging is the gasoline direct injection and that could also 'solve' the moving combustion chamber issue (and the partial burn issues) the rotary has.
And wouldn't you know it the blind squirrel (me ; -) has found a nut!!

From this website. Info on the new Rensis 16x rotary engine from 10/01/07:

Next Generation RENESIS (Rotary Engine 16X)
In developing the next-generation RENESIS, Mazda made a thoroughgoing revision of engine dimensions including the trochoid rotor housing, adopting a longer stroke and larger displacement of 1600cc (800cc x 2) aimed to raise thermal efficiency and boost torque at all engine speeds. By employing the Hydrogen RE design policy of a direct injection system and aluminum side housing, as well as various other measures, we are further promoting the rotary engine’s merits of light weight and compact size.
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      10-05-2007, 11:48 PM   #31
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Its all about the R26B... The sound is just intoxicating...






Quote:
1.The first (and only) Japanese manufacturer race car to win in Le Mans 24 hours endurance race in 1991.

2.the first (and only) overall victory for a car powered by a Wankel rotary engine.

3.After 1991, this car has been banned from entering Le Mans 24 hours race because FIA(Federation Internationalr de l'Automobile) outlawed the use of Wankel-type rotary engines in the racing series due to "unfair weight advantages"
nuff said...
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      10-06-2007, 06:49 AM   #32
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Really neat. DI saves the rotary.

I saw a tuned FD yesterday. Really gave me a sniffle--I do like the rotaries.
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