1.6L Rotary for the next RX7?
07-27-2007, 10:36 AM
#101
Administrator
see that is very important bit of info because, in my understanding, they use a and b to denote the geometry of the engine. a 10a is a different heighth than a 13b. or conversly a 10a and a 13a would be the same heighth but different widths. there is some small difference in eccentricity too, if i understand it all correctly, between a and b. soooooo if the c is being reported accurately then brillo's and RGs remarks about combustion chamber shape for a wider 1.6b
may be on to something. Mazda could have come up with a new height/width/eccentricity combination that deal more with the inherrent ineffeciency of the combustion chamber shape.
or of course it could be just bad reporting
but the biggest single "flaw" with the rotary design is the odd combusion chamber shape which gives rise to all the thermal inefficiency issues and subsequent economy and emissions problems. The smaller that odd combustion chamber shape, the better.
This is why I want a 1.1L turbo motor.
This is why I want a 1.1L turbo motor.
or of course it could be just bad reporting
07-27-2007, 12:08 PM
#102
see that is very important bit of info because, in my understanding, they use a and b to denote the geometry of the engine. a 10a is a different heigth than a 13b. or conversly a 10a and a 13a would be the same heigth but different widths. there is some small difference in eccentricity too, if i understand it all correctly, between a and b. soooooo if the c is being reported accurately then brillo's and RGs remarks about combustion chamber shape for a wider 1.6b
may be on to something. Mazda could have come up with a new height/width/eccentricity combination that deal more with the inherrent ineffeciency of the combustion chamber shape.
or of course it could be just bad reporting
may be on to something. Mazda could have come up with a new height/width/eccentricity combination that deal more with the inherrent ineffeciency of the combustion chamber shape.
or of course it could be just bad reporting
It has been said that the next rotary was going to be a clean slate build so this doesn't surprise me much. Of course you are closer to the pulse than I am and don't need my input on this anyway.
07-27-2007, 12:09 PM
#103
Registered
Join Date: Jun 2005
Posts: 946
Likes: 0
Received 0 Likes
on
0 Posts
For a mainstream product (at least as mainstream as sportscars go) Mazda will need to up the power, significantly up the torque, increase fuel economy and eliminate flooding. These are not real big deals to an enthusiast (I bought the car knowing full well about flooding, low torque and fuel economy).
There was mention a while back of Mazda adding an electric assist motor and I think that combined with a modified renesis including DI is more likely. Provides low end torque, more HP, better MPG and can spin fuel out of the combustion chamber so it won't flood.
They will also need to add a separate oil reservoir and actual oil level gauge. To gain mass market appeal a Rotary needs to be as easy to maintain as a piston engine while providing the low weight, center of gravity that enthusiast desire. If you have a vehicle that requires special attention without amazing benefits it will forever be a low selling niche vehicle.
I wish a tuner out there would put the 2.3 into an RX8 and see what the result would be. The RX8 was intended to be the everyday no compromise (seating for four, four door) sportscar and the Rotary really lends itself to a light weight no frills vehicle similar to Lotus Elise.
There was mention a while back of Mazda adding an electric assist motor and I think that combined with a modified renesis including DI is more likely. Provides low end torque, more HP, better MPG and can spin fuel out of the combustion chamber so it won't flood.
They will also need to add a separate oil reservoir and actual oil level gauge. To gain mass market appeal a Rotary needs to be as easy to maintain as a piston engine while providing the low weight, center of gravity that enthusiast desire. If you have a vehicle that requires special attention without amazing benefits it will forever be a low selling niche vehicle.
I wish a tuner out there would put the 2.3 into an RX8 and see what the result would be. The RX8 was intended to be the everyday no compromise (seating for four, four door) sportscar and the Rotary really lends itself to a light weight no frills vehicle similar to Lotus Elise.
07-27-2007, 12:39 PM
#104
For a mainstream product (at least as mainstream as sportscars go) Mazda will need to up the power, significantly up the torque, increase fuel economy and eliminate flooding. These are not real big deals to an enthusiast (I bought the car knowing full well about flooding, low torque and fuel economy).
There was mention a while back of Mazda adding an electric assist motor and I think that combined with a modified renesis including DI is more likely. Provides low end torque, more HP, better MPG and can spin fuel out of the combustion chamber so it won't flood.
They will also need to add a separate oil reservoir and actual oil level gauge. To gain mass market appeal a Rotary needs to be as easy to maintain as a piston engine while providing the low weight, center of gravity that enthusiast desire. If you have a vehicle that requires special attention without amazing benefits it will forever be a low selling niche vehicle.
I wish a tuner out there would put the 2.3 into an RX8 and see what the result would be. The RX8 was intended to be the everyday no compromise (seating for four, four door) sportscar and the Rotary really lends itself to a light weight no frills vehicle similar to Lotus Elise.
There was mention a while back of Mazda adding an electric assist motor and I think that combined with a modified renesis including DI is more likely. Provides low end torque, more HP, better MPG and can spin fuel out of the combustion chamber so it won't flood.
They will also need to add a separate oil reservoir and actual oil level gauge. To gain mass market appeal a Rotary needs to be as easy to maintain as a piston engine while providing the low weight, center of gravity that enthusiast desire. If you have a vehicle that requires special attention without amazing benefits it will forever be a low selling niche vehicle.
I wish a tuner out there would put the 2.3 into an RX8 and see what the result would be. The RX8 was intended to be the everyday no compromise (seating for four, four door) sportscar and the Rotary really lends itself to a light weight no frills vehicle similar to Lotus Elise.
My sentiments exactly, except for the piston motor in the 8 part.
Paul.
07-27-2007, 01:41 PM
#105
Adding an electric assist motor is going to negate any benifits that putting in a small, lightweight rotary motor will afford you.
And only time will tell if Mazda wants to purse their rotary cars as being more than the small market niche vehicles that they have been in the past.
And only time will tell if Mazda wants to purse their rotary cars as being more than the small market niche vehicles that they have been in the past.
07-27-2007, 01:59 PM
#106
Administrator
iTrader: (7)
I wish Mazda would just release an electronically assisted Turbo like they talked about back in '04.
mpg would suck, but it would a lot of fun (if done properly)
mpg would suck, but it would a lot of fun (if done properly)
07-27-2007, 02:14 PM
#107
Registered
Join Date: Mar 2003
Location: Santiago, Dominican Republic
Posts: 2,525
Likes: 0
Received 0 Likes
on
0 Posts
For a mainstream product (at least as mainstream as sportscars go) Mazda will need to up the power, significantly up the torque, increase fuel economy and eliminate flooding. These are not real big deals to an enthusiast (I bought the car knowing full well about flooding, low torque and fuel economy).
There was mention a while back of Mazda adding an electric assist motor and I think that combined with a modified renesis including DI is more likely. Provides low end torque, more HP, better MPG and can spin fuel out of the combustion chamber so it won't flood.
They will also need to add a separate oil reservoir and actual oil level gauge. To gain mass market appeal a Rotary needs to be as easy to maintain as a piston engine while providing the low weight, center of gravity that enthusiast desire. If you have a vehicle that requires special attention without amazing benefits it will forever be a low selling niche vehicle.
I wish a tuner out there would put the 2.3 into an RX8 and see what the result would be. The RX8 was intended to be the everyday no compromise (seating for four, four door) sportscar and the Rotary really lends itself to a light weight no frills vehicle similar to Lotus Elise.
There was mention a while back of Mazda adding an electric assist motor and I think that combined with a modified renesis including DI is more likely. Provides low end torque, more HP, better MPG and can spin fuel out of the combustion chamber so it won't flood.
They will also need to add a separate oil reservoir and actual oil level gauge. To gain mass market appeal a Rotary needs to be as easy to maintain as a piston engine while providing the low weight, center of gravity that enthusiast desire. If you have a vehicle that requires special attention without amazing benefits it will forever be a low selling niche vehicle.
I wish a tuner out there would put the 2.3 into an RX8 and see what the result would be. The RX8 was intended to be the everyday no compromise (seating for four, four door) sportscar and the Rotary really lends itself to a light weight no frills vehicle similar to Lotus Elise.
No piston thanks!
one technology I think we should look out for is the non asisted start system, the one mazda is developing that does away with the starter motor, and flooding in one strike
07-27-2007, 02:15 PM
#108
Registered
Join Date: Mar 2003
Location: Santiago, Dominican Republic
Posts: 2,525
Likes: 0
Received 0 Likes
on
0 Posts
see that is very important bit of info because, in my understanding, they use a and b to denote the geometry of the engine. a 10a is a different heighth than a 13b. or conversly a 10a and a 13a would be the same heighth but different widths. there is some small difference in eccentricity too, if i understand it all correctly, between a and b. soooooo if the c is being reported accurately then brillo's and RGs remarks about combustion chamber shape for a wider 1.6b
may be on to something. Mazda could have come up with a new height/width/eccentricity combination that deal more with the inherrent ineffeciency of the combustion chamber shape.
or of course it could be just bad reporting
may be on to something. Mazda could have come up with a new height/width/eccentricity combination that deal more with the inherrent ineffeciency of the combustion chamber shape.
or of course it could be just bad reporting
07-27-2007, 03:52 PM
#109
Go Texas Longhorns!
the only problem with the rotary engine nomenclature is that you had some racing engines that were two/three rotors and other wierd names that didn't correspond to the 13B, 20B, 26 etc.....(something like 16G?)
Paul would know better than I the names. Doesn't mean they couldn't really be doing what Zoom suggested. Hey if they can increase the displacement and gain efficiency with a two rotor N/A i'm all for it, but up to this point it seems like it would be easier to go smaller with either FI or more rotors.
Paul would know better than I the names. Doesn't mean they couldn't really be doing what Zoom suggested. Hey if they can increase the displacement and gain efficiency with a two rotor N/A i'm all for it, but up to this point it seems like it would be easier to go smaller with either FI or more rotors.
07-27-2007, 04:15 PM
#110
see that is very important bit of info because, in my understanding, they use a and b to denote the geometry of the engine. a 10a is a different heighth than a 13b. or conversly a 10a and a 13a would be the same heighth but different widths. there is some small difference in eccentricity too, if i understand it all correctly, between a and b. soooooo if the c is being reported accurately then brillo's and RGs remarks about combustion chamber shape for a wider 1.6b
may be on to something. Mazda could have come up with a new height/width/eccentricity combination that deal more with the inherrent ineffeciency of the combustion chamber shape.
or of course it could be just bad reporting
may be on to something. Mazda could have come up with a new height/width/eccentricity combination that deal more with the inherrent ineffeciency of the combustion chamber shape.
or of course it could be just bad reporting
I used to work at a rotary shop, that shall remain nameless for now. Let me clear this up. The overall rotor shape was the SAME between the 10a 12a and 13b. The only thing that changed was the width of the rotors. they were increased by 10MM in each engine I believe. The only reason why the 13B was call the the 13B was because they already had a 13A motor that was used in a FWD luce, that used taller, but narrower rotors, so it could work in a FWD application.
20B got the B just so people would know its 13B based.
07-27-2007, 04:20 PM
#111
on another note, I really believe that when I read about the "ground up redesign for 2010" really makes me think mazda is going to mess with the actual hight of the rotors again... something they havent done since the 60's at least in the major production engines, 13A and prototypes aside.
07-27-2007, 04:22 PM
#112
Administrator
granted its been some time since ive held one in my hand but i would swear the 10a rotors are not the same height(i keep saying this instead of diameter maybe we should use diameter?) as the 13 b rotors
07-27-2007, 04:45 PM
#113
Super Moderator
I used to work at a rotary shop, that shall remain nameless for now. Let me clear this up. The overall rotor shape was the SAME between the 10a 12a and 13b. The only thing that changed was the width of the rotors. they were increased by 10MM in each engine I believe. The only reason why the 13B was call the the 13B was because they already had a 13A motor that was used in a FWD luce, that used taller, but narrower rotors, so it could work in a FWD application.
20B got the B just so people would know its 13B based.
20B got the B just so people would know its 13B based.
Putting aside the FWD Luce 130 with its "narrow" 13 A Rotary.
ALL I repeat ALL Rotaries that were sold in Australia and the US from 1969 have the same rotor shape, it is the width that changes to increase displacement.
ALL 10A and 12A up to around 1973 had twin side seals on their rotors and thick 6mm carbon apex seals.
When Mazda released the RX-4 with the 13B they incorporated the single side seal and thinner apex seals, the 12A also had the same treatment in the form of apex and rotor side seals...in my opinion it should have been called a 12B.
07-27-2007, 04:48 PM
#114
Administrator
okay im apparently loosingmy mind- happens sometimes. the letters do however point to significant design revisions- so the palcement of a "c" would indicate something more than just adding DI- imho
07-27-2007, 04:55 PM
#115
Super Moderator
The rotors spin in the same shaped rotor housing design used in the 10A, 12A, 13B and 20B
Last edited by ASH8; 07-27-2007 at 05:00 PM.
07-27-2007, 05:12 PM
#117
Super Moderator
And IMO if there is a "C" named Rotary it would show a significant change in the dimensions of the rotors and housings.
And I honestly can not see Mazda doing this.
For the last 38 years that I have been following Mazda they have stuck to the same sized engines.
The costs for new manufacturing equipment and tooling IMO would far out weigh any success in future car sales.
Let alone the technical aspects of a "larger" rotary engine that will "work", and deliver to the consumer a car that is also more economical.
YOU CAN FORGET IT IF ANY SO CALLED FUTURE ROTARY ENGINE USES MORE DINO FUELS.
And yes, I have heard that Mazda have said that they are working on a so-called 40% increase in power and or economy from their rotary.
That is a massive achievement and again I can not see how and where,
apart from some form of DI fuel delivery and that is a lot more difficult in a rotary then in a banger engine.
And I honestly can not see Mazda doing this.
For the last 38 years that I have been following Mazda they have stuck to the same sized engines.
The costs for new manufacturing equipment and tooling IMO would far out weigh any success in future car sales.
Let alone the technical aspects of a "larger" rotary engine that will "work", and deliver to the consumer a car that is also more economical.
YOU CAN FORGET IT IF ANY SO CALLED FUTURE ROTARY ENGINE USES MORE DINO FUELS.
And yes, I have heard that Mazda have said that they are working on a so-called 40% increase in power and or economy from their rotary.
That is a massive achievement and again I can not see how and where,
apart from some form of DI fuel delivery and that is a lot more difficult in a rotary then in a banger engine.
07-27-2007, 05:20 PM
#118
Super Moderator
Yep as I said, a "C" design is a lot more than just DI
07-27-2007, 05:22 PM
#119
Administrator
iTrader: (7)
we can always dream, can't we? 
07-27-2007, 05:28 PM
#120
Super Moderator
I don't know how many times over 3 decades I have heard Mazda say that the "new" rotary has a 20 % this or that improvement in either HP or Gas mileage, when the reality is that the improvements have been more like 5% or less.
07-27-2007, 05:36 PM
#121
Super Moderator
on another note, I really believe that when I read about the "ground up redesign for 2010" really makes me think mazda is going to mess with the actual hight of the rotors again... something they havent done since the 60's at least in the major production engines, 13A and prototypes aside.
I would be just as excited as the anyone IF Mazda does continue the rotary past 2010, the rumor here is that it won't happen.
"The RX-8 is the last rotary Mazda will make!"
"The Hydro 8 has been a reliability failure"
07-27-2007, 05:51 PM
#123
Yep, you are spot on mate...
Putting aside the FWD Luce 130 with its "narrow" 13 A Rotary.
ALL I repeat ALL Rotaries that were sold in Australia and the US from 1969 have the same rotor shape, it is the width that changes to increase displacement.
ALL 10A and 12A up to around 1973 had twin side seals on their rotors and thick 6mm carbon apex seals.
When Mazda released the RX-4 with the 13B they incorporated the single side seal and thinner apex seals, the 12A also had the same treatment in the form of apex and rotor side seals...in my opinion it should have been called a 12B.
Putting aside the FWD Luce 130 with its "narrow" 13 A Rotary.
ALL I repeat ALL Rotaries that were sold in Australia and the US from 1969 have the same rotor shape, it is the width that changes to increase displacement.
ALL 10A and 12A up to around 1973 had twin side seals on their rotors and thick 6mm carbon apex seals.
When Mazda released the RX-4 with the 13B they incorporated the single side seal and thinner apex seals, the 12A also had the same treatment in the form of apex and rotor side seals...in my opinion it should have been called a 12B.
Some markets had single side seal 12A motors prior to 74. They also had the 6 mm carbon apex seals and twin distributors. Some early 12As had a 3 hole exhaust port in each rotor housing and some had a single. The 74 and later 12A was actually internally coded 12B due to the amount of differences that emerged with it; 3 mm steel apex seals, single side seals, better water seals, port timing changes and single distributors. They could have actually called it 12B.
I've been around this game since all the rotor housings said "TOYO KOGYO CO. Hiroshima Japan, under license NSU Wankel".
The internal code for the racing version of the 20B was 13G and the 4 rotor was called 13J initially. I could explain the differences between the 26B and the R26B but I'll leave that for another time or maybe another thread.
Paul.
07-27-2007, 11:25 PM
#124
Whatever Mazda does they should be shooting for 300HP to 350HP to keep up with the Nissan 350Z and other cars in its market. A new underpowered RX will just kill the market for this car and basically that would be stupid of Mazda while they have been sitting on a 3 rotor able to put out around 300-350HP NA for YEARS. YEARS.... that is just so sad to think about... for YEARS the 3 rotor has been sitting around and nobody at Mazda thinks to do something with it....
3 rotor or FI a 2 rotor, put get the HP numbers and 0-60 to 1/4mile times down. Its about performance and being competitive in the market, not screwing your supporters over with "raped" 4 port engines missing an oil cooler or doing nothing for years to increase 6 port HP numbers while the competition HP number and 0-60 keeps getting better.
Somebody at Mazda or Ford has to have some shred of common sense and respect for the rotary market. Its not that you can't have a kick *** powerful rotary (at 350HP) , its just that somewhere in the decision process at Mazda, somebody or a group is making very, very bad decisions.
3 rotor or FI a 2 rotor, put get the HP numbers and 0-60 to 1/4mile times down. Its about performance and being competitive in the market, not screwing your supporters over with "raped" 4 port engines missing an oil cooler or doing nothing for years to increase 6 port HP numbers while the competition HP number and 0-60 keeps getting better.
Somebody at Mazda or Ford has to have some shred of common sense and respect for the rotary market. Its not that you can't have a kick *** powerful rotary (at 350HP) , its just that somewhere in the decision process at Mazda, somebody or a group is making very, very bad decisions.
Last edited by sosonic; 07-27-2007 at 11:39 PM.
07-28-2007, 01:43 AM
#125
Super Moderator
More rotary engine trivia:
Some markets had single side seal 12A motors prior to 74. They also had the 6 mm carbon apex seals and twin distributors. Some early 12As had a 3 hole exhaust port in each rotor housing and some had a single. The 74 and later 12A was actually internally coded 12B due to the amount of differences that emerged with it; 3 mm steel apex seals, single side seals, better water seals, port timing changes and single distributors. They could have actually called it 12B.
I've been around this game since all the rotor housings said "TOYO KOGYO CO. Hiroshima Japan, under license NSU Wankel".
The internal code for the racing version of the 20B was 13G and the 4 rotor was called 13J initially. I could explain the differences between the 26B and the R26B but I'll leave that for another time or maybe another thread.
Paul.
Some markets had single side seal 12A motors prior to 74. They also had the 6 mm carbon apex seals and twin distributors. Some early 12As had a 3 hole exhaust port in each rotor housing and some had a single. The 74 and later 12A was actually internally coded 12B due to the amount of differences that emerged with it; 3 mm steel apex seals, single side seals, better water seals, port timing changes and single distributors. They could have actually called it 12B.
I've been around this game since all the rotor housings said "TOYO KOGYO CO. Hiroshima Japan, under license NSU Wankel".
The internal code for the racing version of the 20B was 13G and the 4 rotor was called 13J initially. I could explain the differences between the 26B and the R26B but I'll leave that for another time or maybe another thread.
Paul.
I failed to mention the late 1973-74 RX-4 12A (LA22S) which did have 6 mm apex seals and single side seals, there were not many sold here, only for about 12-18 months, then the RX-4 13B (LA23S) in late 74 early 1975.
The same 13B with minor emission changes was used in the RX-5 (CD23C)
The Australian market did not have 3 hole exhaust port 12A's here, must have been other OS markets.
What do you mean "Internally Coded 12B" as there was never any mention of the Single side seal, Single Distributor, 3mm Apex Seal "Officially being called a 12B, as ALL Service Manuals and parts books /fiche called them 12A even though unofficially we all internally thought the engine should have been called a 12B, even the rotor housings still had 12A stamped on them, but their design was altered to accommodate the new multi veneered coolant seals.
ALL the "SINGLE" changes occurred on the Australian Engines as part of Mazda's REAPS system...Thats "Rotary Engine Anti Pollution System" for
12A (sorry B) and 13B engines.
Pretty simple why the 3 Rotor 20B was called this because it had one extra 13B rotor, halve 13 you get 6.5, so it was called 20B or technically a 19.5B.
The 4 Rotor Engine was in simple terms two 13B's = 26B
Just like a 12A(B) 3 Rotor would be called a 18A (B) if they existed.