MX-5 and RX-8 could merge
05-02-2012, 01:15 PM
#101
The difference is the next rotary will likely use the MX-5 platform and be smaller. The current MX-5 uses the 8's platform, which is why it has gotten bigger.
One thing is for sure...Mazda really has their work cut out for them now with the pending arrival of the FT-86 and BRZ...small, affordable sports cars. A new rotary car will have to be competitive in MPG and price point in order for it to work with these new cars coming out unless they take it more upscale (275+) in the power department.
One thing is for sure...Mazda really has their work cut out for them now with the pending arrival of the FT-86 and BRZ...small, affordable sports cars. A new rotary car will have to be competitive in MPG and price point in order for it to work with these new cars coming out unless they take it more upscale (275+) in the power department.
05-03-2012, 02:20 AM
#102
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The standard Renesis intake and primary/secondary injectors are used, I don't know what the ECU setting are for it, that was done by WGT Auto Developments, I'm just doing the idle and driveability tuning.
They have just made 260 engine hp on an unported Renesis block with their latest exhaust manifold. I hope to get it a ported block on mine early next year with a similar manifold that can still fit in the MX5 engine bay (very tight).
05-03-2012, 08:06 AM
#104
260hp at the flywheel? Right?
Sure is a sweet set up. If by some way 260 rwhp could be reached in this chassis of yours, then it will become a very popular swap. The NA renny engine is pretty tough, if it is treated right.
Actually this is a car Mazda --should have made.
Sure is a sweet set up. If by some way 260 rwhp could be reached in this chassis of yours, then it will become a very popular swap. The NA renny engine is pretty tough, if it is treated right.
Actually this is a car Mazda --should have made.
05-03-2012, 10:44 AM
#105
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260hp at the flywheel? Right?
Sure is a sweet set up. If by some way 260 rwhp could be reached in this chassis of yours, then it will become a very popular swap. The NA renny engine is pretty tough, if it is treated right.
Actually this is a car Mazda --should have made.
Sure is a sweet set up. If by some way 260 rwhp could be reached in this chassis of yours, then it will become a very popular swap. The NA renny engine is pretty tough, if it is treated right.
Actually this is a car Mazda --should have made.
I wished for YEARS that Mazda would build an RX-5. Now they are talking about building an MX-8 ??? THEY ARE GOING THE WRONG WAY !!!
I don't care what the Renisis problems are. I want one in a Miata! Legal for stock class competition. My '04 RX-8 has been a ball, all while running flawlessly. I don't care about gas milage. It's a SPORTS CAR. I think it helps to blow it out in SOLO IIs and red line it at least once every time I drive it.
05-03-2012, 10:46 AM
#106
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The ND Miata will be lighter than the NC. The merge, if they do it, would be a rotary in the Miata. Not a delete of the Miata and put the Miata's engine in the 8. The 8's chassis won't be in production any more.
05-03-2012, 10:59 AM
#107
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Just joking about that old April fool joke. Do not EVER take me seriously on the internet.
05-03-2012, 11:07 AM
#108
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That link is a 404 error. And the possibility that they could merge wasn't an April Fools joke. And being over a month after, it's not something we would make a connection to. 
05-03-2012, 12:28 PM
#109
IMHO: Make 2 packaged RX8's one that offers a triditional 4 cyl. engine that can produce 250hp and the rotary engine. Alot of people love the body style of the 8 with its unique design but cant afford 18mpg with a high mileage commute to work. If the rotary engine is the sole purpose to buy the car you still can but if its looks and a sporty 4 seater coupe then you have an alternative.
05-03-2012, 12:39 PM
#110
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IMHO: Make 2 packaged RX8's one that offers a triditional 4 cyl. engine that can produce 250hp and the rotary engine. Alot of people love the body style of the 8 with its unique design but cant afford 18mpg with a high mileage commute to work. If the rotary engine is the sole purpose to buy the car you still can but if its looks and a sporty 4 seater coupe then you have an alternative.
The RX-8 is done production. It's the Miata that might get a rotary engine option, not a piston option for a chassis that won't be made any more.
05-03-2012, 03:35 PM
#111
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What they should do is Keep the RX-8 in production, and release that Skyactiv-R engine in it. Series II body has only been in production for 3 model years here in the US, and a fourth in Japan.
I know it won't happen, but it would be nice.
Let's hope we don't have to wait too long before the new rotary engined Mazda hits the roads. Lets also hope they don't take two steps back in longevity like they did with the Series 1 engine, either (less oil injection, lower oil pressures, weak ignition system, etc).
BC.
05-04-2012, 03:56 AM
#112
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Right. I expect that is around 220rwhp. It took a full custom intake, custom exhaust and weeks of tuning to get there and seems consistent with results on the US cars modified in a similar way.
With porting, I would expect another another 10% tops, ending up with ~240rwhp and then only if the new exhaust design can actually fit in my engine bay. If the airflow is good enough, a few more rpm at the top-end would help. At the moment, my restrictive exhaust manifold is choking power off above 7500rpm and going above 9000rpm is pointless.
The new exhaust manifold design is running in an off-road racer at the moment and next step is to put one on a stock RX8. After that is done and tested, it will be tried on my MX5.
The MX5 and rotaries seems to go so well together. However, I can see why Mazda wouldn't put a 300bhp 16X rotary in a new 1000kg MX5 platform. Exciting but not mass-market.
The new exhaust manifold design is running in an off-road racer at the moment and next step is to put one on a stock RX8. After that is done and tested, it will be tried on my MX5.
The MX5 and rotaries seems to go so well together. However, I can see why Mazda wouldn't put a 300bhp 16X rotary in a new 1000kg MX5 platform. Exciting but not mass-market.
05-04-2012, 04:16 AM
#114
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I wonder what has happened to 'Aussie' Danny and his NC MX-5 Renny?
His project started nearly 6 YEARS AGO!
https://www.rx8club.com/australia-new-zealand-forum-37/renesis-nc-track-car-build-158121/
His project started nearly 6 YEARS AGO!
https://www.rx8club.com/australia-new-zealand-forum-37/renesis-nc-track-car-build-158121/
05-04-2012, 06:25 AM
#115
Frankly, I think rotary lovers should thank their lucky stars that Mazda still pursues this engine regardless of financial loss after financial loss. I seriously wonder what the total loss has been since the FD RX7? It must be staggering.
I was in my local Mazda dealer a few days ago. I saw a RX8 getting an engine replaced. I asked the guy how often they replace an engine. He said, all the time. There is always one in the shop. I asked him about the mileage on a typical engine replacement. He said it could be anything, including very low mileage.
BTW, I've read a lot of you complaining about what Mazda builds, and how they aren't doing what you want them to. Have you bought any Mazdas that are not rotaries? The Miata is selling fine and has been for a couple of decades. Same with the Mazda3 - Mazda's bread and butter. If you really love the rotary, put your money where your mouth is and buy one of the other great cars they sell. Everything they make has its own Mazda identity, and in, IMO, is better than the competition.
In 2003 I bought a Mazda6 that was awesome in every way. I used to park it next to other mid size sedans, just to show them what a mistake they made. My wife has a CX9 that corners flatter than anything that size should! Yes, I did have a 350z before my RX8, but hey, I saw the light!
These are the cars that finance your next rotary dream. They MAKE money. Rotaries lose money. I love my RX8, but I am objective enough to realise how flawed it is, and that Mazda only pursues it for the (questionably valuable) halo car factor.
Note: I don't work for Mazda, but I do mark out to them, shamelessly.
I was in my local Mazda dealer a few days ago. I saw a RX8 getting an engine replaced. I asked the guy how often they replace an engine. He said, all the time. There is always one in the shop. I asked him about the mileage on a typical engine replacement. He said it could be anything, including very low mileage.
BTW, I've read a lot of you complaining about what Mazda builds, and how they aren't doing what you want them to. Have you bought any Mazdas that are not rotaries? The Miata is selling fine and has been for a couple of decades. Same with the Mazda3 - Mazda's bread and butter. If you really love the rotary, put your money where your mouth is and buy one of the other great cars they sell. Everything they make has its own Mazda identity, and in, IMO, is better than the competition.
In 2003 I bought a Mazda6 that was awesome in every way. I used to park it next to other mid size sedans, just to show them what a mistake they made. My wife has a CX9 that corners flatter than anything that size should! Yes, I did have a 350z before my RX8, but hey, I saw the light!
These are the cars that finance your next rotary dream. They MAKE money. Rotaries lose money. I love my RX8, but I am objective enough to realise how flawed it is, and that Mazda only pursues it for the (questionably valuable) halo car factor.
Note: I don't work for Mazda, but I do mark out to them, shamelessly.
mmmmmm, lets see
2005 rx-8, 2008 CX-7, 2010 Mazda3, and might be coming 2012 or 2012 CX-5
is that good enough ?
05-04-2012, 07:45 AM
#116
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Right. I expect that is around 220rwhp. It took a full custom intake, custom exhaust and weeks of tuning to get there and seems consistent with results on the US cars modified in a similar way.
With porting, I would expect another another 10% tops, ending up with ~240rwhp and then only if the new exhaust design can actually fit in my engine bay. If the airflow is good enough, a few more rpm at the top-end would help. At the moment, my restrictive exhaust manifold is choking power off above 7500rpm and going above 9000rpm is pointless.
With porting, I would expect another another 10% tops, ending up with ~240rwhp and then only if the new exhaust design can actually fit in my engine bay. If the airflow is good enough, a few more rpm at the top-end would help. At the moment, my restrictive exhaust manifold is choking power off above 7500rpm and going above 9000rpm is pointless.
05-04-2012, 08:15 AM
#117
beg to differ a little here RG.
On the intake manifold the vdi is useless and can actually hurt you a little. There are a LOT of casting irregularities within the lim intake runners, the upper part of the intake doesnt balance out the flow perfectly between the rotors ( it cant be perfect but it can be improved on) and the jet air system can cause some unwanted effect on the primary high rpm flow. Short radius cuts can be also made on the runners. It all adds up.
The exhaust ports are not causing as big a problem as once believed in developing power at this level. They continue to cause longtivity issues--it is believed-- but still not proven. IDK?
A bigger throttle body can actually help a little ( yes we already have a 70mm) since this engine doesnt really like "pulling" air. The bigger TB helps low and midrange more than the top end.
Some of the problem is the carry over gases and most people dont realize how much the system voltage can affect them ( with the rx8 pcm) For example--if your alternator is a little weak and you are running a light weight battery --that can have such an afffect that you can get a lean condition in the upper rpms. The pcm actually increases the system voltage to a little over 14 if the injector duty cycle goes over a pre set amount ( in the high rpms).
The mx5 drivetrain has much less friction lost than the 8's. With the right coatings ( i like micro blue) in the trans and diff it can even be further reduced. So you can start comparing the rwhp to the mazda star series car and bingo--you are at or very close to 240 at the rear wheels.
There is also a lot of friction reducing work that can be done on the engine. I really think with the right set up 250 to rw with a na renny can be done in the mx5 chassis with out porting the exhaust.
On the intake manifold the vdi is useless and can actually hurt you a little. There are a LOT of casting irregularities within the lim intake runners, the upper part of the intake doesnt balance out the flow perfectly between the rotors ( it cant be perfect but it can be improved on) and the jet air system can cause some unwanted effect on the primary high rpm flow. Short radius cuts can be also made on the runners. It all adds up.
The exhaust ports are not causing as big a problem as once believed in developing power at this level. They continue to cause longtivity issues--it is believed-- but still not proven. IDK?
A bigger throttle body can actually help a little ( yes we already have a 70mm) since this engine doesnt really like "pulling" air. The bigger TB helps low and midrange more than the top end.
Some of the problem is the carry over gases and most people dont realize how much the system voltage can affect them ( with the rx8 pcm) For example--if your alternator is a little weak and you are running a light weight battery --that can have such an afffect that you can get a lean condition in the upper rpms. The pcm actually increases the system voltage to a little over 14 if the injector duty cycle goes over a pre set amount ( in the high rpms).
The mx5 drivetrain has much less friction lost than the 8's. With the right coatings ( i like micro blue) in the trans and diff it can even be further reduced. So you can start comparing the rwhp to the mazda star series car and bingo--you are at or very close to 240 at the rear wheels.
There is also a lot of friction reducing work that can be done on the engine. I really think with the right set up 250 to rw with a na renny can be done in the mx5 chassis with out porting the exhaust.
05-04-2012, 08:25 AM
#118
Momentum Keeps Me Going
Some of the problem is the carry over gases and most people dont realize how much the system voltage can affect them ( with the rx8 pcm) For example--if your alternator is a little weak and you are running a light weight battery --that can have such an afffect that you can get a lean condition in the upper rpms. The pcm actually increases the system voltage to a little over 14 if the injector duty cycle goes over a pre set amount ( in the high rpms).
05-04-2012, 08:27 AM
#119
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Keep in mind, it would be impossible to keep most of the 8's exhaust, so it's likely that his header is NOT an OEM RX-8 header. NA Miata's exhaust exits the engine on the left, his passenger side. Renny exists on the right, his driver side, and no hump in the floor to fit the oem header. In which case all bets are off, and you can't assume anything.
He said 'restrictive', and it's possible that is simply a sub-optimal custom design trying to get the piping to fit, and he knows it can be improved on.
He said 'restrictive', and it's possible that is simply a sub-optimal custom design trying to get the piping to fit, and he knows it can be improved on.
05-05-2012, 02:27 PM
#124
