3rd Gen General Discussion The place for non-technical discussion about 3rd Gen RX-7s or if there's no better place for your topic

The RX-7 confirmed to be in the pipeline for 2017---RX-Vision Unveil!!

Thread Tools
 
Search this Thread
 
Old 11-16-15, 02:30 PM
  #2951  
Rotor Head Extreme

iTrader: (8)
 
t-von's Avatar
 
Join Date: Apr 2002
Location: Midland Texas
Posts: 6,719
Likes: 0
Received 26 Likes on 17 Posts
Originally Posted by j9fd3s
Rx7 means maybe too much, Rx8 means something, but it has an aftertaste. Cosmo is my choice, it sounds like something, and it has a pedigree.

Rx9 is just a number and some letters, means nothing
Hmm never thought about it from that point of view. You make a great point because the 2015 Chrysler 200 is a far superior car than the old Seabring based model. Chrysler screwed up by re-naming the last gen model the 200 (when it was still based of the old Seabring platform) when the 2015 is all new and based on the Alfa Romeo platform. So the new name is already tarnished. It's having a hard time gaining traction due it's past Seabring history though.

Last edited by t-von; 11-16-15 at 03:05 PM.
Old 11-16-15, 06:01 PM
  #2952  
Rotary Freak

 
2a+RoN's Avatar
 
Join Date: Dec 2001
Location: chandler, AZ
Posts: 2,402
Likes: 0
Received 0 Likes on 0 Posts
Damn, totally missed the above motoring.au link.

450hp with electric turbo and HCCI sounds expensive and complicated. Need hard specs from Mazda right meow!
Old 11-16-15, 06:39 PM
  #2953  
Full Member

 
zaque's Avatar
 
Join Date: Jun 2006
Location: Orlando, FL
Posts: 155
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by BLUE TII
A 450hp 3,000lb RX-Vision is still a bad *** car that others here wanted and I think it *looks* amazing.
If it's 450 hp, it'd be $90k+.
It would have a better power to weight ratio of the NSX and similar one to the GT-R NISMO, let alone obliterating the best 911.

I'm hoping it simply performs around Cayman GTS or GT4 levels, which is low 4s 0-60, feels like a track car for the street that is trying to kill you, and is more reasonably priced around 38-53k.

Originally Posted by Valkyrie
That has WAY too much over hang for a rotary.
1400 kilos? Seriously?
To both of you:
They said they're going for less than a Cayman. Do you guys have any idea how small this car is? The concept smaller overall than the FD and they are talking about making it even smaller for production and not larger.

The engine bay only appears to be less than 20" deep. No way it's fitting a 25"-27.5" LS engine that fits in the FD engine bay. That's how small this car is. Look at pictures of people beside it.

Originally Posted by BLUE TII
The newest rumors/leaks are that the new RX will have 450hp with a turbocharger that uses capacitors/electric asist for initial spool and a rear dual clutch transaxle (we saw 2 pedals on RX-Vision).

Additionally, the CF parts I speculated on earlier were mentioned.

New Mazda RX secrets revealed - motoring.com.au

Sounds like someone's wishlist for sure...
Originally Posted by BLUE TII
This recent article backs up what I was theorizing about the Skyactiv-R 16X possibly using supercritical injection for a sparkplug-less Homogeneous Charge Compression Ignition engine earlier in this thread.

Mazda SkyActiv-R rotary could use compression ignition- Car News | CarsGuide
Pretty much completely unfounded rumors, and I'll explain why:

First off, the HCCI.

HCCI only works at low RPM. Mazda's next generation of Skyactiv piston engines will still use a spark plug at higher RPM.
And they confirm turbo. So how is it going to be HCCI and turbo?
You would need a turbo that's working at idle like diesel, along with using the spark plugs to get it going and spinning the turbo enough for a very high compression ratio of 18:1
That's DOUBLE the compression ratio a lot of past Rotary engines had and you don't use a turbo with 18:1 compression ratio.
The turbo can add to the heat and compression to enable HCCI, but it's very hard to control as the intake and engine temps change.

Then there's the biggest problem with both of these:
You know how bad backpressure is for a rotary, right? I mean... this is the rx7 forums.
One of the big problems is getting all the exhaust to exit after the combustion cycle and not overlap into the next cycle.
You want the least backpressure possible. That's why removing emissions crap improves out reliability an insane amount.

Both of these things greatly increase backpressure.

That hybrid turbo that uses something like i-ELOOP to spin the turbo at low RPM, and draws the turbo to charge it at higher RPM instead of using a wastegate like McLaren is exploring is super cool, but you... understand how much backpressure that creates drawing on the turbo like that? It's a big problem that seems totally unfeasible for me for a rotary.

These also both contradict how they said they're shooting for lighter than a Cayman which is 1310kg(2888lb).
They'd also have to really fail as Engineers to make a car that's heavier than a Cayman despite being significantly smaller, having a much lighter engine, and with them being the people that made the new 2200-2300lb MX-5

What would make a hell of a lot more sense and be so much simpler is simply having a variable geometry turbo, and not cheaping out with spark plugs and adding a third spark plug for each rotor to improve low RPM flame combustion. Maybe even a forth at the top to improve high RPM as well.

Last edited by zaque; 11-16-15 at 06:43 PM.
Old 11-16-15, 06:52 PM
  #2954  
Rotary Enthusiast

 
cosmicbang's Avatar
 
Join Date: Jul 2002
Location: Virginia
Posts: 1,118
Received 4 Likes on 2 Posts
Originally Posted by j9fd3s
Rx7 means maybe too much, Rx8 means something, but it has an aftertaste. Cosmo is my choice, it sounds like something, and it has a pedigree.

Rx9 is just a number and some letters, means nothing
Why not RX-6? It is just a number and some letters, however the previous RX-9 had four doors.

Old 11-16-15, 07:28 PM
  #2955  
is tempted

iTrader: (10)
 
Templeton's Avatar
 
Join Date: May 2006
Location: New Hampshire
Posts: 885
Received 9 Likes on 8 Posts
You're making too many assumptions on technology that hasn't even hit production yet, its very likely that we will see previous limits and ideas on combustion change.

According to this masters thesis the rotary engine can operate over a broader range in hcci than piston engines. It's a long read but very interesting. (pdf file) https://etd.ohiolink.edu/!etd.send_f...osition=inline
Old 11-16-15, 08:17 PM
  #2956  
Moderator

iTrader: (3)
 
j9fd3s's Avatar
 
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,832
Received 2,603 Likes on 1,847 Posts
Originally Posted by zaque
...and adding a third spark plug for each rotor to improve low RPM flame combustion. Maybe even a forth at the top to improve high RPM as well.
3 plugs are part of the rumors i heard.
Old 11-17-15, 10:00 AM
  #2957  
Rotary Enthusiast

iTrader: (7)
 
YELLOWGSLSE's Avatar
 
Join Date: Oct 2001
Location: Atl, GA
Posts: 790
Received 71 Likes on 32 Posts
Originally Posted by zaque
....I'm hoping it simply performs around Cayman GTS or GT4 levels, which is low 4s 0-60, feels like a track car for the street that is trying to kill you, and is more reasonably priced around 38-53k...
Based on everything I've read and gathered (and after reading your entire post, it appears that we've read all of the same things) I think this is EXACTLY what we're going to get. And I can't wait!

Oh, and it will be called "Rx-7". There was an interview with the Design Chief (I think) where he basically said this...

Last edited by YELLOWGSLSE; 11-17-15 at 10:03 AM.
Old 11-17-15, 10:14 AM
  #2958  
Eats, Sleeps, Dreams Rotary

iTrader: (17)
 
neit_jnf's Avatar
 
Join Date: Apr 2003
Location: Around
Posts: 3,908
Received 187 Likes on 135 Posts
Originally Posted by j9fd3s
3 plugs are part of the rumors i heard.
makes sense if going with 16x-like geometry which has an even longer and narrower combustion chamber...
Old 11-17-15, 11:04 AM
  #2959  
rotorhead

iTrader: (3)
 
arghx's Avatar
 
Join Date: Aug 2004
Location: cold
Posts: 16,182
Received 429 Likes on 263 Posts
Originally Posted by YELLOWGSLSE
Based on everything I've read and gathered (and after reading your entire post, it appears that we've read all of the same things) I think this is EXACTLY what we're going to get. And I can't wait!

Oh, and it will be called "Rx-7". There was an interview with the Design Chief (I think) where he basically said this...
yeah but would you buy it NEW though at such a price? They don't make money off guys on internet forums who can't wait until it comes off warranty in the used market.

Hence, Jalopnik people loving a CTS-V manual transmission wagon but nobody actually buying one.
Old 11-17-15, 12:46 PM
  #2960  
Rotary Motoring

iTrader: (9)
 
BLUE TII's Avatar
 
Join Date: Mar 2001
Location: CA
Posts: 8,217
Received 765 Likes on 507 Posts
yeah but would you buy it NEW though at such a price?

Exactly. That is why I say I love it, but won't buy it.

Too easy for me to 450hp my FD or RX-8 for a fraction of the cost.

Now if it offered something I couldn't get in either of those chassis (MX-5 weight), I would be interested in buying new.
Old 11-17-15, 06:26 PM
  #2961  
RX7 NONCONFORMIST

 
rgould's Avatar
 
Join Date: Nov 2005
Location: speedway
Posts: 74
Likes: 0
Received 0 Likes on 0 Posts
After you install all of the US safety crap backup camera blue tooth and nav system all the driver aids that will be required for it to be sold to the masses. I will keep my FD
Old 11-18-15, 11:31 AM
  #2962  
Moderator

iTrader: (3)
 
j9fd3s's Avatar
 
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,832
Received 2,603 Likes on 1,847 Posts
the Fiat miata just landed 2017 Fiat 124 Spider: This Is It, All Official And Stuff
Old 11-18-15, 12:06 PM
  #2963  
Rotary Motoring

iTrader: (9)
 
BLUE TII's Avatar
 
Join Date: Mar 2001
Location: CA
Posts: 8,217
Received 765 Likes on 507 Posts
j9fd3s the Fiat miata just landed 2017 Fiat 124 Spider: This Is It, All Official And Stuff

I predict the love this thing gets in the automotive press may sway Mazda to rethink the MX-5 "not enough power to get in trouble formula".

Return of Mazdaspeed MX-5?
Old 11-18-15, 12:10 PM
  #2964  
Moderator

iTrader: (3)
 
j9fd3s's Avatar
 
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,832
Received 2,603 Likes on 1,847 Posts
Originally Posted by BLUE TII
j9fd3s the Fiat miata just landed 2017 Fiat 124 Spider: This Is It, All Official And Stuff

I predict the love this thing gets in the automotive press may sway Mazda to rethink the MX-5 "not enough power to get in trouble formula".

Return of Mazdaspeed MX-5?
it would be really easy, just sell it with the Fiat engine. i think the fiat is a little clunky looking (the front and the back look like 2 different cars?), but 160hp and some italian should have the thing selling like hotcakes
Old 11-18-15, 12:14 PM
  #2965  
Rotary Enthusiast

 
HiWire's Avatar
 
Join Date: Apr 2009
Location: Toronto
Posts: 1,499
Received 211 Likes on 148 Posts
It seems likely... everyone else is doing turbo cars, and Mazda's turbos have a good track record.
Old 11-18-15, 02:32 PM
  #2966  
Rotary Motoring

iTrader: (9)
 
BLUE TII's Avatar
 
Join Date: Mar 2001
Location: CA
Posts: 8,217
Received 765 Likes on 507 Posts
Yeah, 189ftlbs torque can shred some 195s or whatever MX-5s come on.
Old 11-19-15, 03:57 PM
  #2967  
Senior Member

 
Exidous's Avatar
 
Join Date: Jul 2004
Location: San Antonio
Posts: 473
Likes: 0
Received 9 Likes on 4 Posts
Fiata looks better than Miata IMO.
Old 11-19-15, 04:44 PM
  #2968  
endless build

iTrader: (15)
 
7krayziboi's Avatar
 
Join Date: Nov 2013
Location: Canada , Alberta
Posts: 1,139
Received 26 Likes on 22 Posts
LOL which one ?
Old 11-20-15, 07:46 AM
  #2969  
Rotary Enthusiast

iTrader: (7)
 
YELLOWGSLSE's Avatar
 
Join Date: Oct 2001
Location: Atl, GA
Posts: 790
Received 71 Likes on 32 Posts
Originally Posted by arghx
yeah but would you buy it NEW though at such a price? They don't make money off guys on internet forums who can't wait until it comes off warranty in the used market.

Hence, Jalopnik people loving a CTS-V manual transmission wagon but nobody actually buying one.
I absolutely plan to buy it, NEW.
Old 11-20-15, 10:09 AM
  #2970  
Full Member

 
mastawyrm's Avatar
 
Join Date: Mar 2012
Location: Huntsville, al
Posts: 65
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by arghx
yeah but would you buy it NEW though at such a price? They don't make money off guys on internet forums who can't wait until it comes off warranty in the used market.

Hence, Jalopnik people loving a CTS-V manual transmission wagon but nobody actually buying one.
The subiyota sold pretty well though didn't it? The internet hivemind screams about every car but I think as a demographic it is willing to buy new for roughly $30k and under.
Old 11-20-15, 11:55 AM
  #2971  
Rotor Head Extreme

iTrader: (8)
 
t-von's Avatar
 
Join Date: Apr 2002
Location: Midland Texas
Posts: 6,719
Likes: 0
Received 26 Likes on 17 Posts
Originally Posted by YELLOWGSLSE
I absolutely plan to buy it, NEW.

You and me both! I missed out on buying my fd brand new because I was a broke high school kid at the time. I will wait a couple years though to make sure all the bugs are worked out and to find out if a 3 rotor option will be on the cards.
Old 11-20-15, 05:51 PM
  #2972  
Full Member

 
zaque's Avatar
 
Join Date: Jun 2006
Location: Orlando, FL
Posts: 155
Likes: 0
Received 0 Likes on 0 Posts
I'd bet the Fiata isn't actually faster. I don't know why everyone is assuming it will be.

It has pretty much the same engine as the Abarth 500, and a similar weight. The Abarth 500 went 0-60 in 6.8s. The Fiata is RWD so it'll do better than that, and might have shorter gearing, but still. It's heavier, and its powerband isn't as flat.

Originally Posted by BLUE TII
I predict the love this thing gets in the automotive press may sway Mazda to rethink the MX-5 "not enough power to get in trouble formula".

Return of Mazdaspeed MX-5?
It's likely they have an agreement with FCA not to, and that the Fiata will be priced a bit higher.

They are making a turbo 2.5 for the CX-9. No reason why they couldn't use similar parts in the MX-5 for a Mazdaspeed version.

Originally Posted by arghx
yeah but would you buy it NEW though at such a price? They don't make money off guys on internet forums who can't wait until it comes off warranty in the used market.
If it's around that 38-53k MSRP and has good standard features instead of it costing like 60k to be decently equipped, then yeah I'd buy one new.
Assuming the money I'm making keeps increasing and I can afford it.

Previously I was looking forward to a used Cayman in a few years. I'd rather have a new RX-7 if it's not unreliable and its resale value isn't going to tank.

Last edited by zaque; 11-20-15 at 05:55 PM.
Old 11-20-15, 08:50 PM
  #2973  
Rotary Motoring

iTrader: (9)
 
BLUE TII's Avatar
 
Join Date: Mar 2001
Location: CA
Posts: 8,217
Received 765 Likes on 507 Posts
I'd bet the Fiata isn't actually faster. I don't know why everyone is assuming it will be.

It has pretty much the same engine as the Abarth 500, and a similar weight. The Abarth 500 went 0-60 in 6.8s. The Fiata is RWD so it'll do better than that, and might have shorter gearing, but still. It's heavier, and its powerband isn't as flat.


You might think that just comparing manufacturer's claimed HP figures..

The Abarth 500 regularly puts down more wheel hp on a dynojet stock than factory claimed crank? HP.

The ND MX-5 dynos a very good 140rwhp (testament to Mazda's drivetrain efficiency).

Flat torque is only good if there is torque, at no point does the Abarth 500's "peaky" torque drop below the ND MX-5 torque.

Stock Abarth 500


Stock ND MX-5


And then the fact that turbo cars gain hp so well with light mods...
Old 11-20-15, 09:49 PM
  #2974  
Rotor Head Extreme

iTrader: (8)
 
t-von's Avatar
 
Join Date: Apr 2002
Location: Midland Texas
Posts: 6,719
Likes: 0
Received 26 Likes on 17 Posts
^ Not much drivetrain loss there! You would think the ND was rocking a carbon fiber driveshaft. No???? I know smaller diameter wheel/tire combo helps too.
Old 11-21-15, 12:00 AM
  #2975  
Moderator

iTrader: (3)
 
j9fd3s's Avatar
 
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,832
Received 2,603 Likes on 1,847 Posts
Originally Posted by t-von
^ Not much drivetrain loss there! You would think the ND was rocking a carbon fiber driveshaft. No???? I know smaller diameter wheel/tire combo helps too.
i've been reading the ND service highlights, and Mazda revised basically EVERYTHING, on the car to reduce friction, and other losses. they made the accessories closer together so they could reduce the belt tension, which is controlled by engine oil pressure. the oil pump has two relief valves, one ecu controlled so that the oil pressure is more steady.

when was the last time you worried about the oil pressure fluctuation and the amount of energy that took?


Quick Reply: The RX-7 confirmed to be in the pipeline for 2017---RX-Vision Unveil!!



All times are GMT -5. The time now is 10:09 PM.