New Mazda 'WIDE' (15B) Rotary 2007
01-15-2006, 03:48 PM
#301
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Thread Starter
RG's rotary engine model code post recalled many of the alterations to our much loved rotary engine.
I will talk here of actual cars that made it into export and sale here in Australia and US.
As you know the 13B first appeared for export in the 1974 RX-4 REAPS (LA23S) (Rotary Engine Anti Pollution System) which incorporated Air Pump,"DCV" Deceleration Control Valves, Thermal Reactor-exhaust manifolds, Single Distributor with dual contact/breaker points, etc...
The "B" designation as RG says was to indicate change to the internals of the rotary engine, and usually dimensional change to the limited Luce (RX-4 export name) JDM 13A.
There were many reliability problems as we know with all the early "A" design engines of the early 70's, contrary to popular belief that it was the carbon compound Apex Seal failure giving most of the reliability issues for owners of new Mazda's, it was almost always internal coolant seepage/leaking into the rotor chambers because of the rotor housing's inner "O" ring seal located in the housing's groove, these would usually age/perish/leak (very slowly, initially) at about 2-3 years of age, heat generated by the spark plugs at a concentrate area was part of the cause at cold start up, hot on one side of the chamber cold on the other, all these factors in time reduced the life span of these particular "O' rings, generally at engine rebuild time the Apex seals were about 35-40% worn but of course would be renewed along with other new parts.
To help increase the life span of these engines, the famous cold engine "warm up" regime was invented/recommended to owners to start car and run motor at 1900RPM for about 2-3 minutes, and or when you see the temp gauge needle move from rest position, then you could drive off, this method "helped" even distribution of heat to a gradual temp change around the entire engine before high RPM use. I still think its a good habit to get into.
The "B" series 13B engine first appeared for export in the 1974 RX-4(LA23S) REAPS, the internal changes were, single rotor side seals and springs, 2 pieces Apex seals and springs, improvements in corner seals and springs, improved rotor oil control rings and O rings, but probably the main change to prevent "coolant" leakage was dual compound square shaped rotor housing "O" rings and the installation of metallic strip protectors along the inner side of the inner rotor housing "O" rings.
These changes at the time dramatically improve the reliability of the rotary.
In that period the 12A was given the same internal treatment and used in the 1974 RX-2 REAPS and 1974 RX-3 (S124A) REAPS, Mazda still branded and called these engines 12A's but had all the 13B's modifications as mentioned.
While perhaps Mazda Japan is technically correct in calling these rotaries 12A's our Distributor Service Managers at the time lamented the fact that for "in field" identification/talk and at a customer level they should have been called 12B's as they believed the internal alterations were significant enough to do so.
There were also many internal changes occurring long before the 13B and 12A(B).
The 1973 12A used in the RX-4 (dual distributor (LA22S) ) incorporated single rotor side seals instead of the old dual type in the 1972 RX-2.
The 2 piece Apex seal was first used for export in the 1973 RX-3 10A (S102A).... Automatic Models only for EU markets!, and they were the 5mm Carbon Compound Apex Seal, a one piece was used in all other 10A and 12A's of the dual distributor series.
As I said I am referring to cars exported from Hiroshima not JDM.
Without doubt the most significant change to the rotary was in 1974 with the 13B and the changes mentioned to all B design engines including the 12B sorry A!., giving the engine dramatic improvements in fuel use, engine reliability, and emissions.
The 1975-76 RX-5 had the same 13B at the RX-4, with minor improvements in the REAPS Pollution system.
The 1978 RX-7 (SA22C) 12A was still basically unchanged with some minor corner seal, oil ring compound improvements and the first electronic ignition rotary (No contact/breakers points). A vastly improved pollution system, DCV Valves and Air pump.
The RX-7 (FB and FC) 13B with similar improvements, and the 1991 (FD) 13B-REW Turbo....and the first fuel injected rotaries in these 7's.
The next major change has been the 13B RENISIS, as RG says the only significant design change has been the exhaust porting through the side (cast) housings instead of rotor housings.
I will talk here of actual cars that made it into export and sale here in Australia and US.
As you know the 13B first appeared for export in the 1974 RX-4 REAPS (LA23S) (Rotary Engine Anti Pollution System) which incorporated Air Pump,"DCV" Deceleration Control Valves, Thermal Reactor-exhaust manifolds, Single Distributor with dual contact/breaker points, etc...
The "B" designation as RG says was to indicate change to the internals of the rotary engine, and usually dimensional change to the limited Luce (RX-4 export name) JDM 13A.
There were many reliability problems as we know with all the early "A" design engines of the early 70's, contrary to popular belief that it was the carbon compound Apex Seal failure giving most of the reliability issues for owners of new Mazda's, it was almost always internal coolant seepage/leaking into the rotor chambers because of the rotor housing's inner "O" ring seal located in the housing's groove, these would usually age/perish/leak (very slowly, initially) at about 2-3 years of age, heat generated by the spark plugs at a concentrate area was part of the cause at cold start up, hot on one side of the chamber cold on the other, all these factors in time reduced the life span of these particular "O' rings, generally at engine rebuild time the Apex seals were about 35-40% worn but of course would be renewed along with other new parts.
To help increase the life span of these engines, the famous cold engine "warm up" regime was invented/recommended to owners to start car and run motor at 1900RPM for about 2-3 minutes, and or when you see the temp gauge needle move from rest position, then you could drive off, this method "helped" even distribution of heat to a gradual temp change around the entire engine before high RPM use. I still think its a good habit to get into.
The "B" series 13B engine first appeared for export in the 1974 RX-4(LA23S) REAPS, the internal changes were, single rotor side seals and springs, 2 pieces Apex seals and springs, improvements in corner seals and springs, improved rotor oil control rings and O rings, but probably the main change to prevent "coolant" leakage was dual compound square shaped rotor housing "O" rings and the installation of metallic strip protectors along the inner side of the inner rotor housing "O" rings.
These changes at the time dramatically improve the reliability of the rotary.
In that period the 12A was given the same internal treatment and used in the 1974 RX-2 REAPS and 1974 RX-3 (S124A) REAPS, Mazda still branded and called these engines 12A's but had all the 13B's modifications as mentioned.
While perhaps Mazda Japan is technically correct in calling these rotaries 12A's our Distributor Service Managers at the time lamented the fact that for "in field" identification/talk and at a customer level they should have been called 12B's as they believed the internal alterations were significant enough to do so.
There were also many internal changes occurring long before the 13B and 12A(B).
The 1973 12A used in the RX-4 (dual distributor (LA22S) ) incorporated single rotor side seals instead of the old dual type in the 1972 RX-2.
The 2 piece Apex seal was first used for export in the 1973 RX-3 10A (S102A).... Automatic Models only for EU markets!, and they were the 5mm Carbon Compound Apex Seal, a one piece was used in all other 10A and 12A's of the dual distributor series.
As I said I am referring to cars exported from Hiroshima not JDM.
Without doubt the most significant change to the rotary was in 1974 with the 13B and the changes mentioned to all B design engines including the 12B sorry A!., giving the engine dramatic improvements in fuel use, engine reliability, and emissions.
The 1975-76 RX-5 had the same 13B at the RX-4, with minor improvements in the REAPS Pollution system.
The 1978 RX-7 (SA22C) 12A was still basically unchanged with some minor corner seal, oil ring compound improvements and the first electronic ignition rotary (No contact/breakers points). A vastly improved pollution system, DCV Valves and Air pump.
The RX-7 (FB and FC) 13B with similar improvements, and the 1991 (FD) 13B-REW Turbo....and the first fuel injected rotaries in these 7's.
The next major change has been the 13B RENISIS, as RG says the only significant design change has been the exhaust porting through the side (cast) housings instead of rotor housings.
Last edited by ASH8; 01-15-2006 at 03:58 PM.
01-15-2006, 09:05 PM
#302
the RX-7 book by Yamaguchi states that the "B" represents the specific internal geometry of the rotor housings and rotors, this would explain the "B" in 20B as it shares the same internal dimensions as the 13B
01-16-2006, 01:19 AM
#304
Super Moderator
Thread Starter
Originally Posted by neit_jnf
the RX-7 book by Yamaguchi states that the "B" represents the specific internal geometry of the rotor housings and rotors, this would explain the "B" in 20B as it shares the same internal dimensions as the 13B
While that is correct the chamber dimensions and combustion capacity if all 12A's and 13B's are the same if you were to slice the engine vertically... the difference between the two are the horizontal dimensions or width if the rotors and housings and of course eccentric shaft, this is where and how the CC (cubic capacity) is increased between the 12A and 13B twin rotary engine.
The 20B has an extra rotor (13B size) and rotor housing to make it a three rotor engine.
Last edited by ASH8; 01-16-2006 at 01:32 AM.
09-26-2007, 03:47 AM
#305
Super Moderator
Thread Starter
There is no word from Mazda on a larger rotary. The rumor as it has now become, started here almost 3 years ago with an old member named Booger. He asked what the possibility of a wider engine would be and how it would work. It was nothing more than pure curiosity on his part and he started a discussion to talk about the pros and cons. That discussion slowly led to people actually believing that Mazda was working on one. That's where it came from. There is no "wide" 15B Renesis. It's turned into an urban legend.
WHEELS was aware back in 2002 and reported the brief story in 2005 which started this thread.
There is no "wide" 15B Renesis.
If it is a 1.55 litre, IMO it will be known as a 16C Renesis.
09-26-2007, 06:36 AM
#306
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Think about this.
Back in 74, they where ready for the 15A engine having built multiple pre-production versions but the OPEC oil crisis snuffed it out.
Mazda did the 15A engine by increasing the width by 10mm to 90mm
10A = 60mm
12A = 70mm
13A = 60mm
13B = 80mm
15A = 90mm
It seems logical & perhaps cost effective that they take this direction again.
Since they named the RX-8 engine a 13B-MSP (Renisis=marketing name), any new engine may still get the "B" designation.
Bring on the 15B-MSP I say......................
REgards
Back in 74, they where ready for the 15A engine having built multiple pre-production versions but the OPEC oil crisis snuffed it out.
Mazda did the 15A engine by increasing the width by 10mm to 90mm
10A = 60mm
12A = 70mm
13A = 60mm
13B = 80mm
15A = 90mm
It seems logical & perhaps cost effective that they take this direction again.
Since they named the RX-8 engine a 13B-MSP (Renisis=marketing name), any new engine may still get the "B" designation.
Bring on the 15B-MSP I say......................
REgards
Last edited by DMRH; 09-26-2007 at 06:40 AM.
09-26-2007, 09:02 AM
#307
Registered
It's being called the long stroke engine not the wide engine. Merely widening the engine won't work in this case and apparently they didn't just widen it. I said they couldn't do this a long time ago. It's all around larger. It has to be in order to increase the port area.
Rumors of a larger rotary have been around for years. The 3rd gen RX-7 was rumored by many to have been a 20B. It wasn't. A 15A and even 21A engine have existed in the past as concepts. It's easy to want to see a larger engine.
Rumors are nothing new. It just so happens that this one appears to be finally happening. It only took 30+ years from the origin of the first size increase rumor. This is the Nostradamus of the rotary world. Get a bunch of rumors spread over years and years and then when something happens that fits one of those rumors, just claim you were first to predict it. There have been a bunch of other magazines that have made predictions and had scoops that have never panned out. When you spread out so many different rumors, a change is bound to fit one of them at some point. The origin of the 15 size engine on this forum was a "what if" question posed here several years ago. It's purely coincedental that it just so happened to be a "what if" that actually "might be"!
I'm glad to see a new engine. I just hope we don't see it running on inefficient hydrogen. I'm very happy to know there will always be a rotary at Mazda and that it is not dead (which was also a prediction by some). Hopefully there will always be a Mazda for the rotary to exist at. There is actually more R&D going on in regards to the rotary right now than there has been in decades and that's no rumor!
Rumors of a larger rotary have been around for years. The 3rd gen RX-7 was rumored by many to have been a 20B. It wasn't. A 15A and even 21A engine have existed in the past as concepts. It's easy to want to see a larger engine.
Rumors are nothing new. It just so happens that this one appears to be finally happening. It only took 30+ years from the origin of the first size increase rumor. This is the Nostradamus of the rotary world. Get a bunch of rumors spread over years and years and then when something happens that fits one of those rumors, just claim you were first to predict it. There have been a bunch of other magazines that have made predictions and had scoops that have never panned out. When you spread out so many different rumors, a change is bound to fit one of them at some point. The origin of the 15 size engine on this forum was a "what if" question posed here several years ago. It's purely coincedental that it just so happened to be a "what if" that actually "might be"!
I'm glad to see a new engine. I just hope we don't see it running on inefficient hydrogen. I'm very happy to know there will always be a rotary at Mazda and that it is not dead (which was also a prediction by some). Hopefully there will always be a Mazda for the rotary to exist at. There is actually more R&D going on in regards to the rotary right now than there has been in decades and that's no rumor!
09-26-2007, 09:08 AM
#308
Administrator
but that is not what they have done DRMH. they have made a new engine that is taller with a longer stroke( like the 13a luce/rx-4 in 1973 http://mazdarotary.net/mazda_rx4.htm ) instead of just increasing the width as they have previously done
09-26-2007, 09:14 AM
#310
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It'll be "hydrogen capable" to appease the green people but no one will run it on hydrogen as it won't make but a fraction of the power than any decent fuel can do. I could add a boiler in the truck, turn the rotary into a steam engine, and make more power than pure hydrogen!
09-26-2007, 11:55 AM
#312
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I would really be interested in seeing what a rotary could do with just a little hydrogen supplementation. Running on 100% hydrogen would be completely unrealistic, but having a bottle the size of a nitrous bottle and having around 5% of your mixture being hydrogen might be do-able.
It wouldn't take much H2 to improve combustion characteristics a good bit. The flame speed of H2 is like, 10 times that of gasoline, which helps out on any engine but especially on our elongated combustion chambers I would think. It's sort of like adding kindling to the big logs in your fireplace. Plus you can get away with super lean a/f ratios that a pure gasoline mixture would never tolerate. And you would eliminate problems with flooding as well.
Or at least according to this guy. He's actually quite honest and realistic here--H2 by itself is absolutely not economical right now, and on-board H2 generators can never produce a net gain in MPG. He goes through the calculations and everything.
It wouldn't take much H2 to improve combustion characteristics a good bit. The flame speed of H2 is like, 10 times that of gasoline, which helps out on any engine but especially on our elongated combustion chambers I would think. It's sort of like adding kindling to the big logs in your fireplace. Plus you can get away with super lean a/f ratios that a pure gasoline mixture would never tolerate. And you would eliminate problems with flooding as well.
Or at least according to this guy. He's actually quite honest and realistic here--H2 by itself is absolutely not economical right now, and on-board H2 generators can never produce a net gain in MPG. He goes through the calculations and everything.
09-26-2007, 02:17 PM
#314
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It'll be "hydrogen capable" to appease the green people but no one will run it on hydrogen as it won't make but a fraction of the power than any decent fuel can do. I could add a boiler in the truck, turn the rotary into a steam engine, and make more power than pure hydrogen!
09-26-2007, 04:58 PM
#315
Super Moderator
Thread Starter
The "name" of the Wide engine came from WHEELS not me...but who cares, just proves you aren't the God you think you are 
"It's being called the long stroke engine not the wide engine", if the engine does make final production and we all hope it does then it will be called a 15 or 16C.
IMO 'long stroke' is somewhat of an oxymoron when you talk rotary and may lead to more confusion to the those who are rotary illiterate.
"It's being called the long stroke engine not the wide engine", if the engine does make final production and we all hope it does then it will be called a 15 or 16C.
IMO 'long stroke' is somewhat of an oxymoron when you talk rotary and may lead to more confusion to the those who are rotary illiterate.
09-26-2007, 05:20 PM
#317
Super Moderator
Thread Starter
It's being called the long stroke engine not the wide engine. Merely widening the engine won't work in this case and apparently they didn't just widen it. I said they couldn't do this a long time ago. It's all around larger. It has to be in order to increase the port area.
Rumors of a larger rotary have been around for years. The 3rd gen RX-7 was rumored by many to have been a 20B. It wasn't. A 15A and even 21A engine have existed in the past as concepts. It's easy to want to see a larger engine.
Rumors are nothing new. It just so happens that this one appears to be finally happening. It only took 30+ years from the origin of the first size increase rumor. This is the Nostradamus of the rotary world. Get a bunch of rumors spread over years and years and then when something happens that fits one of those rumors, just claim you were first to predict it. There have been a bunch of other magazines that have made predictions and had scoops that have never panned out. When you spread out so many different rumors, a change is bound to fit one of them at some point. The origin of the 15 size engine on this forum was a "what if" question posed here several years ago. It's purely coincedental that it just so happened to be a "what if" that actually "might be"!
I'm glad to see a new engine. I just hope we don't see it running on inefficient hydrogen. I'm very happy to know there will always be a rotary at Mazda and that it is not dead (which was also a prediction by some). Hopefully there will always be a Mazda for the rotary to exist at. There is actually more R&D going on in regards to the rotary right now than there has been in decades and that's no rumor!
Rumors of a larger rotary have been around for years. The 3rd gen RX-7 was rumored by many to have been a 20B. It wasn't. A 15A and even 21A engine have existed in the past as concepts. It's easy to want to see a larger engine.
Rumors are nothing new. It just so happens that this one appears to be finally happening. It only took 30+ years from the origin of the first size increase rumor. This is the Nostradamus of the rotary world. Get a bunch of rumors spread over years and years and then when something happens that fits one of those rumors, just claim you were first to predict it. There have been a bunch of other magazines that have made predictions and had scoops that have never panned out. When you spread out so many different rumors, a change is bound to fit one of them at some point. The origin of the 15 size engine on this forum was a "what if" question posed here several years ago. It's purely coincedental that it just so happened to be a "what if" that actually "might be"!
I'm glad to see a new engine. I just hope we don't see it running on inefficient hydrogen. I'm very happy to know there will always be a rotary at Mazda and that it is not dead (which was also a prediction by some). Hopefully there will always be a Mazda for the rotary to exist at. There is actually more R&D going on in regards to the rotary right now than there has been in decades and that's no rumor!
A lesson on "rumors" over fact.??
Does everything have to turn it into a pissing competition.
09-26-2007, 05:53 PM
#318
Administrator
long stroke is what it is being called because that is what they have done- increased the stroke. if that somehow confuses rotary or non- rotary peopel i would be happy to explain it. just point them to this forum.
second- you are the one popping up threads saying "see i told you so" so you are the one engaged in pissing. do i really need to bring up the threads from 2003 where we discussed 15bs etc to get you to stop saying "wheels said it first"?
as far as hydrogen i dont think i should have to repeat myself and previous links to hydrogen filling stations in japan and europe- they can easily be found in previous conversations between RG and I.
but here are 2 relevant links to Hydrogen infrastructure building one in Norway /scandanavia
http://www.renewableenergyaccess.com...story?id=31012
an here are plans for california
http://www.portfolio.com/culture-lif...Car-Wars#page3
second- you are the one popping up threads saying "see i told you so" so you are the one engaged in pissing. do i really need to bring up the threads from 2003 where we discussed 15bs etc to get you to stop saying "wheels said it first"?
as far as hydrogen i dont think i should have to repeat myself and previous links to hydrogen filling stations in japan and europe- they can easily be found in previous conversations between RG and I.
but here are 2 relevant links to Hydrogen infrastructure building one in Norway /scandanavia
http://www.renewableenergyaccess.com...story?id=31012
an here are plans for california
http://www.portfolio.com/culture-lif...Car-Wars#page3
09-26-2007, 06:10 PM
#319
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Everyone keeps saying 16C . . . since this is a completely new design (in terms of trochoid size and width), wouldn't this new engine be called 16A?
09-26-2007, 06:13 PM
#320
It'll be "hydrogen capable" to appease the green people but no one will run it on hydrogen as it won't make but a fraction of the power than any decent fuel can do. I could add a boiler in the truck, turn the rotary into a steam engine, and make more power than pure hydrogen!
09-26-2007, 06:19 PM
#321
Administrator
no because "A" has been used and this geometry is different. 1.55l so 15c or 16c depending on who's rounding- and for that we have to wait for some official release for the Tokyo show
09-26-2007, 06:26 PM
#322
Administrator
better link to the California "Hydrogen Highway"
http://www.cleantechblog.com/2007/04...spans-800.html
it now extends from Chula Vista near the mexican border to Arcata in the norht near Oregon. ther ewill be several filling stations between there and the washington border in oregon in the next coupla years.
the infrastructure is coming. heck i might just put a NG hydrogen reformer at my house so i can fill up a hydrogen car at home
http://www.cleantechblog.com/2007/04...spans-800.html
it now extends from Chula Vista near the mexican border to Arcata in the norht near Oregon. ther ewill be several filling stations between there and the washington border in oregon in the next coupla years.
the infrastructure is coming. heck i might just put a NG hydrogen reformer at my house so i can fill up a hydrogen car at home
09-26-2007, 06:33 PM
#323
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Last edited by Renesis_8; 09-11-2011 at 01:19 PM.
09-26-2007, 06:39 PM
#324
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Here are a few of the rumors that have been stated in magazines over the years:
1: New RX-7 with larger rotary engine (apparently at least part of that will be happening)
2: New RX-7 with Renesis power
3: New RX-7 with Turbo Renesis power
4: New RX-7 with hybrid electric rotary power
5: New RX-7 with Turbo Hydrogen Renesis
6: New RX-7 coming in 2005
7: New RX-7 coming in 2006
8: New RX-7 coming in 2007, 2008, 2009, 2010, 2011, etc... (the more years you predict, the higher your odds)
9: (Here's a good one) 4th gen RX-7 coming in 2000!
10: (Here's an old one) 3rd gen RX-7 to be equipped with naturally aspirated 3 rotor. (1988)
11: New twin turbo Renesis RX-7 on the way.
12: 2 new rotary cars coming. (2004)
13: Facelifted RX-8 coming. (2007) This one is fact though!
14: 2nd generation RX-8 coming (2005)
15: No 2nd generation RX-8 coming.
16: Rotary powered option for new Miata
17: Then there's always the oldie but goodie, "the rotary is dead". Keep in mind Mazda says the rotary is forever!
Take your pick. With that much variety, at least one of them is bound to be true at some point. Even if nothing happened, that would still make #15 true.
Here's a hint about stroke, the 13B has 1.5" of total peak to peak "stroke". The 13A was narrower but had a longer stroke. How? It's easy.
09-27-2007, 02:47 AM
#325
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I didn't even know you had a history with RG and Zoom44. Now it makes better sense.
Ash, you are the one who a few months ago claimed the ROTARY IS DEAD according to your "sources," thus setting off a panic in this forum. Now we know the rotary isn't close to dead.
What you did is the equivalent of falsely shouting "fire" in a hotel or "bomb" at an airport. In the best case, you would be beaten and spit on. Worst case, you would be shot.