Why are Mazda persisting with the Rotary Wankel engine?
Discussion
The Wookie said:
300bhp/ton said:
While I don't disagree with the above. I do wonder how easy you could have an RX-8 type vehicle with either a Boxer 4 turbo or a compact V6 like the Rover KV6. Either setup could match the hp of the rotary and I'm not convinced they are actually that much bigger and heavier. But I admit I have no stats to hand. 
I can't quote exact dimensions, but to me the Renesis looks about half the size of a Toyota 3.5 V6, and it's reputed to weigh about the same fully dressed as a K-seriesHarji said:
Ask me, I think i's wonderful, compact, rev's to 9000rpm. A rotary engine has won Le Mans 24 hour, people did buy the car.
It did get some help from the ACO.Harji said:
The engine is lightweight, as shown earlier,
No we've seen that it is smaller than other engines but no weights.Harji said:
rb5230 said:
But what makes the rx8 any more of a "sports car" than the 130i? its slower and less powerful for a start. I thought sports cars were all meant to be 2 seaters?
But I suppose its just profile and shape that make a sports car, personally i would rather whichever was more capable rather than which was labled "sports car".
the 130i is part of the 1 series model range which includes the diesels, the RX-8 was designed specifically as a sports car, like the MX-5, lotus (name your model), Porsche Boxster.But I suppose its just profile and shape that make a sports car, personally i would rather whichever was more capable rather than which was labled "sports car".
There are definitions on the web, but the 130i is just a big lump in the car with a few tweaks.
Chrysler Crossfire and Mercedes SLK spring to mind as being a couple of cars designed to be "sports cars" but are bettered in every conceivable way by plenty of cars designed by plenty of manufacturers and of which are based around the modest diesel or 1.4 petrol hatchback base models.
rb5230 said:
The point i was trying to make was that just because a car is designed from the ground up to be a "sports car" it does not automatically mean it is any better than a car which is very closely related to a mundane diesel hatchback but has been changed to be become quicker and more sporty.
Chrysler Crossfire and Mercedes SLK spring to mind as being a couple of cars designed to be "sports cars" but are bettered in every conceivable way by plenty of cars designed by plenty of manufacturers and of which are based around the modest diesel or 1.4 petrol hatchback base models.
Fair do, but like I said, you can get a BMW 1 series and plant diesel engines and later 3litre turbo's, it's not a sports car, your model range is a eco diesel and very fast hatchback.Chrysler Crossfire and Mercedes SLK spring to mind as being a couple of cars designed to be "sports cars" but are bettered in every conceivable way by plenty of cars designed by plenty of manufacturers and of which are based around the modest diesel or 1.4 petrol hatchback base models.
The RX-8 was developed around the engine, you can not get another engine in it, it's not based on anything else the car was created for what it is, a 2+2 (classic sports car layout) RWD fantastic handling car. I really dont care if you cant get your golf clubs in it (you probably can, I don't have any). I tested a few cars and this one was the best handling, can I really say anything more?
As for weight, a lot of people I think don't understand about weight distribution as well, it's all well saying every car is 50/50, but the where the weight is just as important, Mazda have it where most people can only dream off, hint look at where the engine is and how low it is in the bulk head.
Oh, and I have driven a 1 series, don't even go there in comparison to handling and excitement.
Camaro91 said:
I heard one the other day. Sounded w
k - give me a dirty low output V8 anyday 
!
I guess this guy agreed.k - give me a dirty low output V8 anyday !http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Maybe the best car build thread on PH.
rb5230 said:
Harji said:
If you want a 5 seater hatchback then the BMW 130i is your car, however ugly it is, but if you want a Sports car then the RX-8 is your choice. You're trying to blur the Mazda in to too many catogries. It's a sports car, the BMW 130i is not by definition a sports car. A fast car yes, but spors car, no.
But what makes the rx8 any more of a "sports car" than the 130i? its slower and less powerful for a start. I thought sports cars were all meant to be 2 seaters? reckon its pretty hard for a 4 seater sports car to only have 2 seats 
But more seriously
its the feel of how they drive. i.e. a BMW e30 325i is a faster car than a Mazda MX-5, but they will feel very different to drive. It's the same with the 130i, its a very capable fast car that might have some 'sporting' intentions. But it's not a sports car.interweb said:
RX-8 R3
es, we’re horsepower freaks, but we also value athletic response. And the RX-8 has long been our poster car in this regard. Mazda’s unique hummer was the slowest sprinter in both of its previous track meets, yet its fancy footwork prevailed on the score cards. Nimble, however, takes you only so far, and the RX-8 enters its seventh year largely unchanged.
Tweaks? Sure. Notably the R3 model ($5495 more than a basic RX-8), which includes a killer 300-watt Bose audio system, Bluetooth hands-free phone connectivity, Recaro seats, traction and stability control, a rear wing, rocker-panel extensions, fog lights, xenon headlights, a stiffened front suspension crossmember, higher spring rates, firmer damping via Bilstein shocks, and 19-inch aluminum alloy wheels wearing Bridgestone Potenza RE050A 225/40-19 tires.
It’s the functional elements of that collection that add authority to the RX-8’s sports-car credentials. A little more grip, a little quicker turn-in, a little quicker recovery in transient response. On mountain roads, the RX-8 still holds its own among this more powerful pack, albeit with the driver rowing the six-speed gearbox in search of the cog that will grant maximum thrust.
Thanks to a body shell that verges on race-car rigid—remarkable, considering those rear demi-doors and the absence of B-pillars—plus the location of the engine’s compact mass (low and behind the front axle), the RX-8 has a refined level of balance and grace. The firm embrace of the Recaros and the precision of the electric power steering keep the driver aware of every nuance, creating that rare sense of man-machine partnership that’s the essence of sports-car fun.
The R3 enhancements, however, have provisos. Ride quality, already firm in other RX-8 versions, is firmer still, and there’s porpoising and expansion-joint whacking on patchy stretches of freeway. Plus, a lot of noise comes up through the suspension. Some of us like the turbinesque sounds of the rotary as it spools up and down, but the car can’t be called quiet. Another gripe: The bolstering of the Recaros is welcome on the track but becomes just short of oppressive, for some, on long freeway runs, putting relentless pressure on the hip bones.
The RX-8’s virtues are by now well known. Interior materials are top quality, the rear-hinged half-doors provide easy rear-seat access, and there’s room back there for two adults to travel in reasonable comfort. The combination of the rear door framing and the hefty C-pillars creates rear-quarter blind spots, but forward sightlines are exemplary, and there are no ergonomic mysteries.
Beyond that, the RX-8 still looks snappy with its freshened face and racy add-ons. The price, too, is attractive. But against an opponent that can match its finesse and leave it gasping for breath at the drag strip, the Mazda comes up short. The rotary engine makes the RX-8 unique, but beyond that, its benefits are difficult to perceive. It’s light on torque, short on horsepower, and thirsty when pressed (a dismal 14 mpg in this test). Mazda is reportedly working on a direct-injection rotary that will address these limitations, but that could be a couple of years away.
From the same article:es, we’re horsepower freaks, but we also value athletic response. And the RX-8 has long been our poster car in this regard. Mazda’s unique hummer was the slowest sprinter in both of its previous track meets, yet its fancy footwork prevailed on the score cards. Nimble, however, takes you only so far, and the RX-8 enters its seventh year largely unchanged.
Tweaks? Sure. Notably the R3 model ($5495 more than a basic RX-8), which includes a killer 300-watt Bose audio system, Bluetooth hands-free phone connectivity, Recaro seats, traction and stability control, a rear wing, rocker-panel extensions, fog lights, xenon headlights, a stiffened front suspension crossmember, higher spring rates, firmer damping via Bilstein shocks, and 19-inch aluminum alloy wheels wearing Bridgestone Potenza RE050A 225/40-19 tires.
It’s the functional elements of that collection that add authority to the RX-8’s sports-car credentials. A little more grip, a little quicker turn-in, a little quicker recovery in transient response. On mountain roads, the RX-8 still holds its own among this more powerful pack, albeit with the driver rowing the six-speed gearbox in search of the cog that will grant maximum thrust.
Thanks to a body shell that verges on race-car rigid—remarkable, considering those rear demi-doors and the absence of B-pillars—plus the location of the engine’s compact mass (low and behind the front axle), the RX-8 has a refined level of balance and grace. The firm embrace of the Recaros and the precision of the electric power steering keep the driver aware of every nuance, creating that rare sense of man-machine partnership that’s the essence of sports-car fun.
The R3 enhancements, however, have provisos. Ride quality, already firm in other RX-8 versions, is firmer still, and there’s porpoising and expansion-joint whacking on patchy stretches of freeway. Plus, a lot of noise comes up through the suspension. Some of us like the turbinesque sounds of the rotary as it spools up and down, but the car can’t be called quiet. Another gripe: The bolstering of the Recaros is welcome on the track but becomes just short of oppressive, for some, on long freeway runs, putting relentless pressure on the hip bones.
The RX-8’s virtues are by now well known. Interior materials are top quality, the rear-hinged half-doors provide easy rear-seat access, and there’s room back there for two adults to travel in reasonable comfort. The combination of the rear door framing and the hefty C-pillars creates rear-quarter blind spots, but forward sightlines are exemplary, and there are no ergonomic mysteries.
Beyond that, the RX-8 still looks snappy with its freshened face and racy add-ons. The price, too, is attractive. But against an opponent that can match its finesse and leave it gasping for breath at the drag strip, the Mazda comes up short. The rotary engine makes the RX-8 unique, but beyond that, its benefits are difficult to perceive. It’s light on torque, short on horsepower, and thirsty when pressed (a dismal 14 mpg in this test). Mazda is reportedly working on a direct-injection rotary that will address these limitations, but that could be a couple of years away.
interweb said:
BMW 135i
Highs, Lows, and Verdict
Highs: Lots of smooth midrange turbo power, supple on all surfaces, all-around competence.
Lows: Not at its happiest on a track, not as pretty as a 3-series coupe but almost as expensive.
The Verdict: More of an outstanding sports coupe than a real sports car.
It was a bit too comfy, a bit too quiet, a bit too refined to be a sports car.Highs, Lows, and Verdict
Highs: Lots of smooth midrange turbo power, supple on all surfaces, all-around competence.
Lows: Not at its happiest on a track, not as pretty as a 3-series coupe but almost as expensive.
The Verdict: More of an outstanding sports coupe than a real sports car.
superman84 said:
300bhp/ton said:
hat would you call a lightweight 4 seater sports car then?
I was responding to the comment that the "Mazda RX-8 is about power and light weight" when in reality it is not particularly lightweight or powerful. There are plenty of bigger more powerful cars which don't weigh a great deal more. The older Imprezas for instance weigh less than an RX8 and have more power and an AWD system. That's not to take away from the handling abilities of the RX8 or its fun factor though, just saying its hard to see the benefits of the wankel.kev b said:
Does anyone know the reason why Mazda did not sell a rotary engined MX5?
No. And I can honestly say it baffles me why there wasn't an RX-5 optioned car, maybe a bit more racey, lightweight and focused and gone after the lower end Elise type market. Reckon it'd have been a success in America as well as the UK and JDM.Interesting article 300bhp. All the more so about the sound, as I have an R3 and quite a few people like the Rotary sound, it's certainly more pronounced than the MK1.
I disagree, it has the same creature comforts as the first gen, but that is their opinion, most magazines and opinions have classed it as a sports car and gets tested with the like as well.
In fact most reviews (all?) have been very positive about the RX-8!
I disagree, it has the same creature comforts as the first gen, but that is their opinion, most magazines and opinions have classed it as a sports car and gets tested with the like as well.
In fact most reviews (all?) have been very positive about the RX-8!
A rotary engined MX-5 would be great. I would guess that the reasons they haven't done so are:
To really get the benefit of the tiny engine, you'd have to redesign the car to make the most of it. The MX-5's long bonnet isn't really needed, you could tuck the engine right up under the bulkhead and shorten the front. But if you did that, the normal four pot wouldn't fit.
Product positioning - it would tread on the toes of the bigger RX model.
High running costs for a cheap little roadster.
Going against the MX-5 "tradition".
There was a company in Germany making them, though;
http://www.youtube.com/watch?v=ilmr-0XE02c
To really get the benefit of the tiny engine, you'd have to redesign the car to make the most of it. The MX-5's long bonnet isn't really needed, you could tuck the engine right up under the bulkhead and shorten the front. But if you did that, the normal four pot wouldn't fit.
Product positioning - it would tread on the toes of the bigger RX model.
High running costs for a cheap little roadster.
Going against the MX-5 "tradition".
There was a company in Germany making them, though;
http://www.youtube.com/watch?v=ilmr-0XE02c
Harji said:
Interesting article 300bhp. All the more so about the sound, as I have an R3 and quite a few people like the Rotary sound, it's certainly more pronounced than the MK1.
I found the standard setup a bit too muted, but nothing that can't be fixed with a good stainless steel catback and maybe a new intake. I like this one, though the Borla was a bit louder than I wanted to inflict on my neighbours, so I went RacingBeat instead.http://www.youtube.com/watch?v=1o4mfhza0yU
Harji said:
Interesting article 300bhp. All the more so about the sound, as I have an R3 and quite a few people like the Rotary sound, it's certainly more pronounced than the MK1.
I disagree, it has the same creature comforts as the first gen, but that is their opinion, most magazines and opinions have classed it as a sports car and gets tested with the like as well.
In fact most reviews (all?) have been very positive about the RX-8!
They have to an extent. The fundamental problem is they aren't as fuel efficient as an equivalent power output otto. Given the price of fuel, this is going to be a problem for the majority of potential buyers.I disagree, it has the same creature comforts as the first gen, but that is their opinion, most magazines and opinions have classed it as a sports car and gets tested with the like as well.
In fact most reviews (all?) have been very positive about the RX-8!
There are too many problems to be solved with materials and the like to make it viable in the short term. Sadly, this has been true since the RO80.
Harji said:
Oi_Oi_Savaloy said:
I'm not having a go at Mazda for being alternative - just asking the question why persist with something that appears to be useless? Even if the packaging is awesome people are not going to be buying a car that does 20mpg.
Why on earth do you think it is useless? Ask me, I think i's wonderful, compact, rev's to 9000rpm. A rotary engine has won Le Mans 24 hour, people did buy the car. It's funny how people can drive a V8 and cope with it's thirst. I drive an RX-8 and cope with it's thirst, is that so hard for people? As I have mentioned before, handled far better than a 335i BMW along the B-roads.
my only thoughts are that the RX8 is too heavy, you can pick up some proper bargains, just gotta ask the right questions to see if the owners a muppet, me i'd prefer an RX 2,3 or 4 coupe, downside is there super rare in this country :S
Harji said:
is more efficient in it's conversion to power (no four strokes)
erm, not really - otherwise it wouldn't get such poor mpg 
it has a higher specific output, yes - but as mentioned earlier, there was another thread recently about this - accelerating the pistons does NOT require energy*, and doesn't waster any more in friction than a wankel rotor tip
- at steady state - accelerating an engine from 1000 to 3000rpm requires energy, some of which is the pistons, but holding at a constant rpm the losses come from friction, dragging air through the system, and load from ancillaries.
eldar said:
They have to an extent. The fundamental problem is they aren't as fuel efficient as an equivalent power output otto. Given the price of fuel, this is going to be a problem for the majority of potential buyers.
It's getting to that point, although some people are still willing to swallow worse fuel consumption and no more power in return for a V8 soundtrack or a razor sharp throttle response or not using Satan's fuel - or for the handling benefits of a favourable weight distribution.If we were all driven by the calculus of mpg per bhp, we would all drive BMW diesels.
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