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RIWWP 12-14-2009 02:44 PM


Originally Posted by Shoafb (Post 3351904)
If they threw a piston engine in an RX and didn't tell you I would imagine you would be equally pissed. :yesnod:

Fair enough. I can't argue that. :)

blackenedwings 12-14-2009 02:49 PM


Originally Posted by Shoafb (Post 3351904)
because I don't want to deal with a Rotary.

Again why Mazda needs to generate a rotary that has a reputation for reliability. People are terrified of the engine.

Also, sneaking a rotary into a traditionally piston engine car would be a disaster for everyone. Offering it as an engine option would be smart. Hell the MX-5 has a bunch of shared systems with the RX-8, dropping a Renesis into the MX-5 wouldn't even be that hard and would probably sell pretty well. It wouldn't throw off the weight of the MX-5 and would up the power by a lot over the piston variant.

Fuel economy isn't an area I think the rotary is ever going to compete in as best in class. It will always be on the low end of the sports car economy line, but if someone is buying a sports car based off the fuel economy they are a goddamn idiot.

What Mazda can compete with is light weight, superb handling, and the main area they need to get their game on is reliability. I also think they need to raise power output, but a turbocharger would make reliability worse not better so its certainly an issue for them. If they offer a new rotary vehicle it should come with at least an option for a turbocharged variant from the factory... Mazdaspeed or High-power etc, naturally aspirated rotaries don't generate enough torque.

All of that is worthless though if they can't prove the rotary engine can at least match traditional piston engines for reliability. If they can't they might as well give up on the engine because it will just suck money down the drain.

CyberPitz 12-14-2009 03:16 PM


Originally Posted by Shoafb (Post 3351904)
I had an o4 Mustang Mach1. Ripping a burnout from a standstill in 2nd gear was fun as heck... ( before replacing the tires of course... ) the Miata is a hell of a lot funner to drive though.

The OP stated Mazda should throw the Rotary in there, sneak it in to be exact, without telling anyone... thus the.... I would be PISSED remark. Not because of the tainted Miata image but because I don't want to deal with a Rotary.

If they threw a piston engine in an RX and didn't tell you I would imagine you would be equally pissed. :yesnod:

Aahh, yeah, that makes sense. I read it as "If they put it in there, sales would drop". You're rendition makes more sense now :rofl:

olddragger 12-14-2009 03:40 PM

Hey Aaron

I was not talking about what FI system performs the best in given situations. I mentioned the supercharger because that is the way manufactuers are going. The Mustang the Corvette, the lotus, tundra trucks etc. I am not aware of any NEW turbo cars out there. I admit there may be some--I just dont know about them. After market supercharger kits are out for the 350Z , and the G 35's etc. Just seems to be more of them now a days. SC are simpler systems to install and maintain--i will stand on that. They will not put out as much performance gains as a big turbo--data speaks for itself. But how much power is enough for the car maker?

A supercharged 16x would give plenty of tq for street use dude---come on! Probably over 200.

Heat on a turbo is an issue. To simplify --if it wasnt why all the shielding? I dont want to get techical here.

Anytime there are more parts in a system it automatically causes the system to become more complex. Which system has the most parts that are different from an NA engine? Do you really believe a turbo system is less complex than a s.c. system?
You do realize that a low boost s.c. with w/m will not need an intercooler?

Water methanol system maintainance is filling up your winshield washer like tank every 2 months--thats not much for a true perfomance sports car and think of the talk it will cause! Yea baby

Its going to be hard to get weight down? But heck yea I will take it lower--i was just mainly pointing out the hp/wgt ratio range that I thought would be good. If we can get to 10/1 --uh huh!

I dont mean to get into a turbo/sc discussion here. There is nothing wrong with a good, correctly installed turbo system---nothing at all. Neither system is perfect. But, I would suspect also that aftermarket driveway beginning owners would be tinkering with the turbo system to get more boost were as you cannot do that with a s.c. (until someone makes bigger pulleys).
Anyway that is basically where I was coming from
rotor on dude!
olddragger

Chad D. 12-14-2009 04:08 PM

A turbo/SC option would be prime.
All Aluminum would be a +.
That car is a beautiful render.
I would buy that. Sell the SUV, and make the 8 the family car.

Shoafb 12-14-2009 04:20 PM


Originally Posted by blackenedwings (Post 3351930)
Again why Mazda needs to generate a rotary that has a reputation for reliability. People are terrified of the engine.

Also, sneaking a rotary into a traditionally piston engine car would be a disaster for everyone. Offering it as an engine option would be smart. Hell the MX-5 has a bunch of shared systems with the RX-8, dropping a Renesis into the MX-5 wouldn't even be that hard and would probably sell pretty well. It wouldn't throw off the weight of the MX-5 and would up the power by a lot over the piston variant.

Fuel economy isn't an area I think the rotary is ever going to compete in as best in class. It will always be on the low end of the sports car economy line, but if someone is buying a sports car based off the fuel economy they are a goddamn idiot.

What Mazda can compete with is light weight, superb handling, and the main area they need to get their game on is reliability. I also think they need to raise power output, but a turbocharger would make reliability worse not better so its certainly an issue for them. If they offer a new rotary vehicle it should come with at least an option for a turbocharged variant from the factory... Mazdaspeed or High-power etc, naturally aspirated rotaries don't generate enough torque.

All of that is worthless though if they can't prove the rotary engine can at least match traditional piston engines for reliability. If they can't they might as well give up on the engine because it will just suck money down the drain.


1. reliabilitly is going to take time, that's all there is to it. They really messed up with the 8 early on, especially the 4 speed AT ( of cousre this is what the wife bought.... LOL ) . Agreed they must be able to match the reliability of a piston engine. Just saying "well look how light the engine is and how great the car handles" won't cut it. There are lots of awesome handling piston powered cars out there and most will never come close to pushing the limits of the car anyway.


2. True, when buying a sports car fuel economy is really silly to complain about but I think what the problem the 8 faces is the HP/TQ gains that are expected with that poor mpg. 18/22 mpg rating and folks expect 300+ if not more these days.

Mazmart 12-14-2009 06:31 PM


Originally Posted by olddragger (Post 3352006)
Hey Aaron

I was not talking about what FI system performs the best in given situations. I mentioned the supercharger because that is the way manufactuers are going. The Mustang the Corvette, the lotus, tundra trucks etc. I am not aware of any NEW turbo cars out there. I admit there may be some--I just dont know about them. After market supercharger kits are out for the 350Z , and the G 35's etc. Just seems to be more of them now a days. SC are simpler systems to install and maintain--i will stand on that. They will not put out as much performance gains as a big turbo--data speaks for itself. But how much power is enough for the car maker?

A supercharged 16x would give plenty of tq for street use dude---come on! Probably over 200.

Heat on a turbo is an issue. To simplify --if it wasnt why all the shielding? I dont want to get techical here.

Anytime there are more parts in a system it automatically causes the system to become more complex. Which system has the most parts that are different from an NA engine? Do you really believe a turbo system is less complex than a s.c. system?
You do realize that a low boost s.c. with w/m will not need an intercooler?

Water methanol system maintainance is filling up your winshield washer like tank every 2 months--thats not much for a true perfomance sports car and think of the talk it will cause! Yea baby

Its going to be hard to get weight down? But heck yea I will take it lower--i was just mainly pointing out the hp/wgt ratio range that I thought would be good. If we can get to 10/1 --uh huh!

I dont mean to get into a turbo/sc discussion here. There is nothing wrong with a good, correctly installed turbo system---nothing at all. Neither system is perfect. But, I would suspect also that aftermarket driveway beginning owners would be tinkering with the turbo system to get more boost were as you cannot do that with a s.c. (until someone makes bigger pulleys).
Anyway that is basically where I was coming from
rotor on dude!
olddragger

Although your car is MORE THAN INCREDIBLE (And I mean it), normal people :eyetwitch aren't going to do the rituals that you do.

Paul :).

olddragger 12-14-2009 08:42 PM

Hey Paul I know i am sick.:) and i am loving it.

Flash i dont want to sound like I am arguing---dont mean to do that.
I guess different opinions is what makes the world go around. You have good ideas and i respect them. Keep them coming man.
Merry Christmas dude.
OD

Renesis_8 12-14-2009 09:23 PM

I don't think we should worry what platform the engine is put into yet.

The problem Mazda is facing now is they can't get the 16X to run well. I don't believe in everything the reports say, but we've only heard nothing but bad news so far about the new prototype rotary engine.

1) Not enough revs - very possible due to heavier and bigger rotors
2) DI making it too heavy - really?? its hard to buy into that
3) Their DI system isn't a true DI, meaning injecting and then burning in the same rotor face = greatly reduced chamber cooling effects and precise burning, its like a better version of port injection
4) Fuel economy not meeting expectation
5) Awaiting reports of the reliability of the Series II RX-8 engines

I think any new rotary sports car will have to wait for the development of the 16X to finish. It doesn't make much sense to put the RX-8 engine into another platform. Even in a 2700lb package, it will at best achieve acceptable gas mileage. None of us care much about the gas mileage, but it is indeed a problem. And the Series I engine can't outlast a 20 year old NA rotary.

6) Maybe the all Aluminum construction is giving them problems too, unforeseen problems


Mazda is the expert in making platforms, from Mazda 2 to CX-9, which platform isn't even a concern at all, they can make a 2500lb RX-7 that handles on rails anyday.
________
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zoom44 12-14-2009 10:48 PM


Originally Posted by Renesis_8 (Post 3352514)
3) Their DI system isn't a true DI, meaning injecting and then burning in the same rotor face = greatly reduced chamber cooling effects and precise burning, its like a better version of port injection


well i dont know. If you can picture the fuel being sprayed just before that rotor tip passes the injector i think that its started compression at that point

http://www.autoweek.com/storyimage/C...16x-rotary.jpg

zoom44 12-14-2009 10:54 PM

i can't see the rotors being heavier. they are slightly taller but they are also narrower. I bet the issue with revs is the mass being farther from the center so exerting higher centripetal force on the e-shaft(of course thats why it has higher torque: longer lever;)). probably need a better front bearing or even a center support bearing.

Symbioticgenius 12-14-2009 11:18 PM

Ok.

My last post was a bit misleading, and I'm shocked that it was taken as it was. I never intended for Mazda to sell Miata's marked as 4 Cyl's with Rotaries instead.
That is A. Illegal, and will kill Mazda,
B. Immoral and will kill Mazda,
C. Stupid, and will Kill Mazda.

I used Microsofts Mojave experiment
http://blogs.zdnet.com/hardware/?p=2311
as an example to give an idea to what I meant.
Give a Focus group 100 Miatas, to keep for 2 Summer months. (I volunteer).
Half get a 2 Rotor, Half get 4 Cyl. Don't tell them some are Rotaries, just say hey, try the new Miata out for us and give us feedback.
Obviously make them sign not to tinker with motor, or even pop the hood \ lift the car etc, but allow them to take it to the track, or drive normally, or use as they see fit, period.

After the 2 months is up, collect the feedback, video tape the results, and break the news that their car was a Rotary or not, etc. Compare it to the feedback that people gave from the 4 Cyls.

If all goes well, this could be an amazing promotional tool, seeing the 70 year old dude talking about how awesome the car felt, didn't notice any hesitation, flooding, low torque, etc.
Even if it doesn't go well, make them sign disclosure agreements and use the data to improve the rotary to meet the standards set by the other motor.

Its win \ win.

Renesis_8 12-14-2009 11:30 PM


Originally Posted by zoom44 (Post 3352643)
(of course thats why it has higher torque: longer lever;)).

You sure it is not because it is heavier? :cool:

Hmm.. I am sure you have seen Mazda's DISI, or other DI system. The benefits of DI comes mainly from igniting the fuel as soon as (or while, I'm not sure about the timing) they're injected. If they could put the DI injector closer to the sparkplug, then a much better fuel economy can be expected.

Even before they've released pictures of 16X, I imagined the DI injectors to be just above the sparkplugs, perhaps spraying fuel down into the plugs, then they're ignited.

When I saw the first pictures of 16X, the location of the injectors surprised me a little. But what do I know, I ain't an engineer.
________
Latin Girl Live

Renesis_8 12-14-2009 11:33 PM


Originally Posted by zoom44 (Post 3352634)
well i dont know. If you can picture the fuel being sprayed just before that rotor tip passes the injector i think that its started compression at that point

I can picture it. It should be on the same face. You're right.
________
big women Webcams

j_tso 12-15-2009 02:57 AM

You mean like this?
http://homepage.mac.com/jolocho/iiRE.png

Originally Posted by Rotary Engine by Kenichi Yamamoto
Fig. 5.3 is also a development by Audi-NSU. It is of high pressure intermittent injection type timed for injection in the compression stroke.
As described above, the rotary engine gives much wider freedom than the reciprocating engine for selecting the location of the injection nozzle, injecting direction, injection timing, etc. Especially, many studies on the working chamber injection type are also being performed as a means of forming a stratified mixture, as described in 5.2.

That's from 1981!

Shoafb 12-15-2009 09:12 AM


Originally Posted by Symbioticgenius (Post 3352677)
Ok.

My last post was a bit misleading, and I'm shocked that it was taken as it was. I never intended for Mazda to sell Miata's marked as 4 Cyl's with Rotaries instead.
That is A. Illegal, and will kill Mazda,
B. Immoral and will kill Mazda,
C. Stupid, and will Kill Mazda.

I used Microsofts Mojave experiment
http://blogs.zdnet.com/hardware/?p=2311
as an example to give an idea to what I meant.
Give a Focus group 100 Miatas, to keep for 2 Summer months. (I volunteer).
Half get a 2 Rotor, Half get 4 Cyl. Don't tell them some are Rotaries, just say hey, try the new Miata out for us and give us feedback.
Obviously make them sign not to tinker with motor, or even pop the hood \ lift the car etc, but allow them to take it to the track, or drive normally, or use as they see fit, period.

After the 2 months is up, collect the feedback, video tape the results, and break the news that their car was a Rotary or not, etc. Compare it to the feedback that people gave from the 4 Cyls.

If all goes well, this could be an amazing promotional tool, seeing the 70 year old dude talking about how awesome the car felt, didn't notice any hesitation, flooding, low torque, etc.
Even if it doesn't go well, make them sign disclosure agreements and use the data to improve the rotary to meet the standards set by the other motor.

Its win \ win.

You really think half that focus group, without knowing anything about a rotary, would not flood it? Look how many 8's got flooded and people where told how to avoid it. Just cause they don't know there is a rotary in there doesn't mean they won't notice the low tourqe at low rpm either.

You would have the old guy saying " I pulled it out to wash it and now the POS won't start... had to have it towed back to the dealer and all the plugs where changed... what kind of crap is this?"

arghx7 12-15-2009 09:19 AM

^^ yeah when old NSU engineers in Germany still worked on rotaries

dillsrotary 12-15-2009 10:09 AM

I can't imagine DI adding a ton of weight, yes you'll need to pressurize the fuel to extreme PSI's but on most modern applications it adds about 20 lbs total. (18 lbs to be exact on the new porsche 3.8 flat 6) The main benefit of the system is a cooler charge.

olddragger 12-15-2009 10:37 AM

maybe they need a 3 sparkplug per rotor set up?
i wonder if they are having trouble with cylinder(rotary face) wash?
Mazda needs to make a 3 or 4 rotor supercar? The mazda name needs a flagship?
OD

Goingfastnowhere 12-15-2009 11:38 AM

I say put the renniy in the mx-5, change the final gear, upgrade the suspension and make the car a bit wider . Do the same test as Symbioticgenius suggested, he truly is a genious.

Price the car at an introductory rate around 1k less than the RX8 R3 and still give the 100k warranty,

The new rennys have the 6 oil squirters so i doubt that they are going to have the same issues as the first gen rx8s are having. Upgraded starter, battery and better spark. With all of this, I dont see an issue with flooding.


OMG!!! Rx8+Mx5=RX5!!!! Smaller, faster, convertible rotary!!! Its like having an 85 rx7... lol That would be my next car if mazda puts it in its line up. Until then i will keep my rx8. And down the line ill build me and mx5 with a renny, maybe with a supercharger to make things fun! =D

Shoafb 12-15-2009 11:53 AM


Originally Posted by Goingfastnowhere (Post 3353268)
I say put the renniy in the mx-5, change the final gear, upgrade the suspension and make the car a bit wider . Do the same test as Symbioticgenius suggested, he truly is a genious.

Price the car at an introductory rate around 1k less than the RX8 R3 and still give the 100k warranty,

The new rennys have the 6 oil squirters so i doubt that they are going to have the same issues as the first gen rx8s are having. Upgraded starter, battery and better spark. With all of this, I dont see an issue with flooding.


OMG!!! Rx8+Mx5=RX5!!!! Smaller, faster, convertible rotary!!! Its like having an 85 rx7... lol That would be my next car if mazda puts it in its line up. Until then i will keep my rx8. And down the line ill build me and mx5 with a renny, maybe with a supercharger to make things fun! =D

But the circa 85 rotary was a different beast. Those engines would go over 200k wouldn't they? They didn't build up carbon like the newer designs do.. they didn't have to pass the newer more strict emmisions test.

JRichter 12-15-2009 12:14 PM


Originally Posted by Goingfastnowhere (Post 3353268)
I say put the renniy in the mx-5, change the final gear, upgrade the suspension and make the car a bit wider . Do the same test as Symbioticgenius suggested, he truly is a genious.

Price the car at an introductory rate around 1k less than the RX8 R3 and still give the 100k warranty,

The new rennys have the 6 oil squirters so i doubt that they are going to have the same issues as the first gen rx8s are having. Upgraded starter, battery and better spark. With all of this, I dont see an issue with flooding.


OMG!!! Rx8+Mx5=RX5!!!! Smaller, faster, convertible rotary!!! Its like having an 85 rx7... lol That would be my next car if mazda puts it in its line up. Until then i will keep my rx8. And down the line ill build me and mx5 with a renny, maybe with a supercharger to make things fun! =D

Agreed but offer a true fastback/hatchback coupe similar in size/packaging to FD and I would be at the Mazda dealer in a heartbeat.


Originally Posted by Shoafb (Post 3353096)
You really think half that focus group, without knowing anything about a rotary, would not flood it?


Do people still flood there 8's? I can't/have never been able to flood mine no matter how hard I try. I start it cold in the morning in 0 deg temp, drive across the street to gas station and shut down 2 mins later w/o temp dial even moving, fill up and it starts right up. This happens probably once a month. I've moved it countless times cold and come back 36-48 hours later to go somewhere and starts right up.

MattMPS 12-15-2009 12:25 PM

I have been skepitcal about the possibilities of 16x to meet the tuff emission standard for the future (i mean particulary Co2 emissions), behind this news there is a revision of the project into an hybrid rotary engine....smaller than the 16x an maybe electro-assisted turbocharged..they have patented also A 1.0 litre (is it correct?)

just my 2 cents

RIWWP 12-15-2009 02:08 PM


Originally Posted by JRichter (Post 3353335)
Do people still flood there 8's? I can't/have never been able to flood mine no matter how hard I try. I start it cold in the morning in 0 deg temp, drive across the street to gas station and shut down 2 mins later w/o temp dial even moving, fill up and it starts right up. This happens probably once a month. I've moved it countless times cold and come back 36-48 hours later to go somewhere and starts right up.

Yes, flooding is still fairly frequent, but it has nothing to do with cold temps, or even "below optimal temp" on startup. Every single flooding I have seen in the past year has been due to a degrading ignition system that couldn't produce a strong enough spark to ignite, normally because the owner wasn't aware that the ignition system doesn't last 40k, 50k, 60k, (or even 83k from someone)

Which is why I keep mentioning the ignition system as something Mazda needs to beef up and make sure that it last at least 60k completely trouble free and in perfect condition (not just adequate), if not 100k. (except spark plugs, people accept the need to change those every ~30k on piston engines anyway). That plus required lubrication and required cooling will dramatically impact their reliability perception for the better.

Shoafb 12-15-2009 02:30 PM

[QUOTE=RIWWP;3353492]. (except spark plugs, people accept the need to change those every ~30k on piston engines anyway).

They do? :scratchhe

Can't think of a modern car that requires a 30k spark plug change.


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