Full Review and Driving Impressions: 2019 Mazda MX-5 Miata ND2

The Miata is back. We used that lede before to introduce the ND-chassis MX-5, but this time we really mean it. Really.

It’s not like the Miata ever really left, but the ND did feel slightly undercooked. It wasn’t the basic chassis, though. That was spot-on: small, light and nimble, just like the original.

It was the engine. And, as we now know, it was a compromise. Worldwide, including here in the U.S. of A., the ND-chassis MX-5 was supposed to get a lightweight, free-revving, 1.5-liter engine. It’s a momentum car, not a big-block Corvette, Mazda has always stressed.

But officials at Mazda North American Operations said that wouldn’t work. The car needed a bigger engine. So, somewhat at the last minute, a 2.0-liter was shoehorned under the hood.

Bigger is better, right? Generally, yes, but this one wasn’t quite a sports car engine. It felt a bit like a passenger car engine wearing some trick running shoes. The entire package still worked, but something was lacking.

That lack has now been filled. For 2019, the MX-5 gets a very revived engine. We discussed the 2019 Mazda MX-5 Miata ND2’s changes already, but here’s a quick rundown: larger throttle body, improved intake manifold, larger-diameter tubes for the exhaust header, more aggressive exhaust cam, lighter connecting rods, improved fuel injection, and lower piston domes that help the tumble flow of the air-fuel mixture. A stiffer crankshaft allows for a higher rpm. For more details, check out Mazda’s PowerPoint presentation.

But about that new redline: Mazda says that these changes allow the revised engine to spin to 7500 rpm, an 800 rpm increase over the original ND mill. Those numbers were mentioned in the press materials released back in June, and they were reiterated during the August press launch.

Then we drove the car. Although we saw the new MX-5 reach a GPS-verified 59 to 60 mph in second gear, an improvement over the original ND, our eyes told us that the fuel cutoff was occurring before 7500 rpm. When we dyno tested the 2019 Mazda MX-5 Miata ND2 the new ND2 at Z Car Garage, in fifth gear the redline seemed to kick in right around the 7200 rpm mark.

We even went back to dyno operator and shop owner Rob Fuller: Was the car actually revving to 7500 and we were just misreading things? Nope. He confirmed that redline really did come in earlier.

The new car still goes faster in second gear than its predecessor, and Andy Hollis’s analysis of the data contains good news for C Street autocrossers.

Quick trip back in time: When we originally tested the ND, we found it to reach 55 mph in second gear on taller-than-stock 225/45R17 BFGoodrich Rival S tires. (We tested that particular car against Chris Harvey’s autocross-prepared NC MX-5, which could hit 58.5 in second on the same tires.)

So we went back and looked at the dyno charts shown during the press introduction’s PowerPoint presentation. Looks like the redline on those charts is also closer to 7200 rpm than 7500. The plot thickens.

On August 6, Jacob Brown, product communications specialist at Mazda North American Operations, issued the following statement: “Attached is the 2019 MX-5 PowerPoint presentation as a PDF. There has been a minor brouhaha on the Miata forums about the graph presented with the horsepower numbers, as it appears to show the ND2’s engine redlining at 7,200 rpm. The presentation was not to scale, so the numbers are a little off, ND1 vs. ND2. Please refer to the additional slides, attached, for the proper graphs, should you need them.”

Mazda MX-5 Miata ND2 Dyno Chart

One more update was issued from Mazda on August 10:

“The car has a low-gear, transient conditions redline of 7500 rpm (basically, when you are driving aggressively on a track). Otherwise, its steady state redline when you’re driving the car casually is 7200 rpm.”

Brian Goodwin from Good-Win Racing also commented on the dyno graphs:

“Yes, 2019 ND2 power at the wheels on dynojet equals ND1 with tune/header for peak hp on same brand of dyno. That’s about what we expected, curious to see what we get with header/tune on ND2. Still a big gap in torque to tuned ND1.

“More curious is that we expected the promised 7500 redline, perhaps this is a smart ECU with ‘break in’ mileage minimum required before giving us the promised 7500 rpm redline?

“For comparison, tuned ND1 dyno below with our ‘Max Torque’ RoadsterSport on same brand of dyno, a Dynojet. Numbers are 166 for hp, 160 on torque.

Mazda MX-5 Miata ND1 Dyno Chart

“Note that ND1 motors don’t give up the full numbers when new, they test higher after a few thousand miles of break-in driving/racing,” he continued.

Numbers aside, what’s the updated MX-5 like to drive? It feels just like a Miata. Don’t fear the dual-mass flywheel—you won’t think there’s a manhole cover attached to the end of the crankshaft. The revived engine reminds us of the original 1.6. It’s happy, like a puppy.

The recalibrated throttle response, though, is a step up from the cable arrangement used back in the day. As Mazda notes, the 2019 engine’s throttle response has been tweaked. The goal: a more linear feel that actively cancels drivetrain oscillation. Those are their words, not ours, but we can tell you that throttle response feels super-smooth. We tried to make the drivetrain buck, pulling the classic move of shifting into a too-tall gear at a too-slow speed. The engine just pulled away—no bucks, no hesitation. The updated throttle action makes the MX-5 feel like a higher-end car, and we mean that in a good way.

The rest of the car, including the gearing, is pretty much unchanged. The suspension and brakes are carried over, although a backup camera and oil cooler have been added to the spec sheet. And yes, the radio/navigation controls are still located in the console, putting them a bit in the way.

The new exhaust sounds great. It’s not loud or boomy. It doesn’t drone at highway speeds.

Total weight gain: just 7 pounds, Mazda says.

We’re intrigued by the new GT-S package, which pairs the high-end interior with the Bilstein suspension and limited-slip diff. Baby Porsche, anyone?

Final verdict on the updated MX-5: Even if it doesn’t rev all the way to 7500, it’s still an improvement over its predecessor, which was already a really, really good car.

Join Free Join our community to easily find more Mazda news.
Comments
View comments on the GRM forums
mazdeuce - Seth
mazdeuce - Seth Mod Squad
8/13/18 8:37 a.m.

Looking forward to a straight answer on the 7200-7500 thing. I'd hate for that to be a blemish on what is otherwise a fantastic car.

Tom Suddard
Tom Suddard Digital Experience Director
8/13/18 8:39 a.m.

The answer in the article is basically it: Theoretically, under certain conditions, it will rev to 7500. We couldn't get past 7200 on the street or on the dyno.

n8
n8 New Reader
8/13/18 9:05 a.m.

Otherwise, its steady state redline when you’re driving the car casually is 7200 rpm.

I don't know about you guys, but I casually hit rev limiters all the time.

Keith Tanner
Keith Tanner MegaDork
8/13/18 9:30 a.m.

I drove a 2019 in to work this morning. And I hit an indicated 7500 on the way in without doing anything weird. I see nothing wrong with this.

It's a 2018 with magic fun sprinkles. There is no downside.

The 2016-18 cars have a variable rev limiter too, but it's less sophisticated and it appears nobody else noticed it.

mazdeuce - Seth
mazdeuce - Seth Mod Squad
8/13/18 9:39 a.m.

In reply to Tom Suddard :

A theoretical redline that might be higher under some circumstances that you can't predict is.......not good. This run might be 59mph, or it might not.....

Tom Suddard
Tom Suddard Digital Experience Director
8/13/18 9:41 a.m.

It's possible our car was under a break-in program or something funny like that, too, but who knows. We'll be getting another one in a week or two for a full week, which will give us the time to dig deeper.

Keith Tanner
Keith Tanner MegaDork
8/13/18 9:48 a.m.

Only internet forums can take a car that's just like the old one but better and come up with problems.

2016s have variable rev limiters. Nobody else noticed, but it's there.

Vigo
Vigo UltimaDork
8/13/18 9:58 a.m.

I got rid of one of my favorite cars over not getting the same thing every time i floored it. Hopefully whatever the conditions are for the higher redline are able to be hit consistently under race conditions, otherwise it won't be as much of an upgrade for racers as previously thought. 

Keith Tanner
Keith Tanner MegaDork
8/13/18 10:08 a.m.

The dyno is a very artificial environment, it does things you wouldn't see in the real world. We'll be testing our car on the track and the dyno, we'll see how it really behaves.

Even if you consistently get 7200 instead of 7500, that's still 600 rpm and horsepowers better than the '18.

Andy Hollis
Andy Hollis
8/13/18 10:39 a.m.

What matters most to me is whether I can get 7500 in gears 2-4 for consistent lap behavior on the track.  Being able to continue to pull longer in 4th instead of 5th, when the car is really working hard against drag, makes a big difference.  And knowing it will be the same every lap, is also key.

Keith...if you have a 2019 at hand, do us all a favor and run it up through each gear at WOT and see where it hits the limiter, please.

 

Keith Tanner
Keith Tanner MegaDork
8/13/18 10:52 a.m.

I'm not sure I'm going to manage to hit the limiter in 6th, that's over 180 mph wink. We'll do dyno testing in gears. The '16 has a gear-dependent redline and you know how that behaves, we'll compare the two.

Vigo
Vigo UltimaDork
8/13/18 10:55 a.m.

Even if you consistently get 7200 instead of 7500, that's still 600 rpm and horsepowers better than the '18.

 

Keith, I get where you're coming from but the problem is that my brain responds far better to the mediocre than to the asinine. If that applies to enough people, the whole 'guess your redline' game might be a big turnoff. What are the paremeters?

MiataRoadster
MiataRoadster None
8/13/18 11:32 a.m.

lede?

Keith Tanner
Keith Tanner MegaDork
8/13/18 12:16 p.m.
Vigo said:

Even if you consistently get 7200 instead of 7500, that's still 600 rpm and horsepowers better than the '18.

 

Keith, I get where you're coming from but the problem is that my brain responds far better to the mediocre than to the asinine. If that applies to enough people, the whole 'guess your redline' game might be a big turnoff. What are the paremeters?

Give us a bit more time to learn the car, we'll know more about when (if) it limits the engine speed. It's kind of disappointing that everyone is latching on to this, which may or may not be actually a problem. The '19 is fantastic news, it's an evolution of the ND that has no downside.

Just like the 2016-18, the car has a lower redline in higher gears. Any dyno shop that's tested an ND should know this, and it's a shame that GRM wasn't aware and they decided to do investigative journalism without that piece of information. 7500 rpm in 5th is over 150 mph, and it's unlikely the car will actually get there in the real world so it's an academic difference. Somehow, all those C Stock guys battling it out have managed to deal with a variable redline without noticing. But now the conversation has been turned from what the car is like to drive to a bunch of forums and journalists (all over the place) latching on to a sensationalist story without hard data - and dyno runs are not hard data in this case. I feel bad for the Mazda PR guys.

Tom Suddard
Tom Suddard Digital Experience Director
8/13/18 12:49 p.m.
APEowner
APEowner Dork
8/13/18 3:21 p.m.
Keith Tanner said:
Vigo said:

Even if you consistently get 7200 instead of 7500, that's still 600 rpm and horsepowers better than the '18.

 

Keith, I get where you're coming from but the problem is that my brain responds far better to the mediocre than to the asinine. If that applies to enough people, the whole 'guess your redline' game might be a big turnoff. What are the paremeters?

Give us a bit more time to learn the car, we'll know more about when (if) it limits the engine speed. It's kind of disappointing that everyone is latching on to this, which may or may not be actually a problem. The '19 is fantastic news, it's an evolution of the ND that has no downside.

Just like the 2016-18, the car has a lower redline in higher gears. Any dyno shop that's tested an ND should know this, and it's a shame that GRM wasn't aware and they decided to do investigative journalism without that piece of information. 7500 rpm in 5th is over 150 mph, and it's unlikely the car will actually get there in the real world so it's an academic difference. Somehow, all those C Stock guys battling it out have managed to deal with a variable redline without noticing. But now the conversation has been turned from what the car is like to drive to a bunch of forums and journalists (all over the place) latching on to a sensationalist story without hard data - and dyno runs are not hard data in this case. I feel bad for the Mazda PR guys.

Wait till somebody notices that wide open throttle doesn't actually open the throttle all the way all the time!  Sometimes I hate the proliferation of cheap chassis dynos.

 

APEowner
APEowner Dork
8/13/18 3:24 p.m.
Tom Suddard said:

In reply to MiataRoadster :

https://www.merriam-webster.com/dictionary/lede

I learned a new word.  That doesn't happen very often anymore.  I also learned that I've been misunderstanding the expression "bury the lead".  It's actually "bury the lede".  The things you learn on the GRM forum.

Keith Tanner
Keith Tanner MegaDork
8/13/18 3:30 p.m.
APEowner said:
Keith Tanner said:
Vigo said:

Even if you consistently get 7200 instead of 7500, that's still 600 rpm and horsepowers better than the '18.

 

Keith, I get where you're coming from but the problem is that my brain responds far better to the mediocre than to the asinine. If that applies to enough people, the whole 'guess your redline' game might be a big turnoff. What are the paremeters?

Give us a bit more time to learn the car, we'll know more about when (if) it limits the engine speed. It's kind of disappointing that everyone is latching on to this, which may or may not be actually a problem. The '19 is fantastic news, it's an evolution of the ND that has no downside.

Just like the 2016-18, the car has a lower redline in higher gears. Any dyno shop that's tested an ND should know this, and it's a shame that GRM wasn't aware and they decided to do investigative journalism without that piece of information. 7500 rpm in 5th is over 150 mph, and it's unlikely the car will actually get there in the real world so it's an academic difference. Somehow, all those C Stock guys battling it out have managed to deal with a variable redline without noticing. But now the conversation has been turned from what the car is like to drive to a bunch of forums and journalists (all over the place) latching on to a sensationalist story without hard data - and dyno runs are not hard data in this case. I feel bad for the Mazda PR guys.

Wait till somebody notices that wide open throttle doesn't actually open the throttle all the way all the time!  Sometimes I hate the proliferation of cheap chassis dynos.

 

The stuff the ND does with the throttle plate is fascinating. Really, it's not a throttle pedal but a torque request. The car runs a vacuum pump because of the times the butterfly is open under "vacuum" conditions.

AnthonyGS
AnthonyGS New Reader
8/13/18 4:54 p.m.

I plan to test drive a 19 ND and an 09-12 Boxster or Boxster S next spring with the wife and see which one makes more sense for us.  Consider they are both in the same ballpark price wise, I bet we end up with the more expensive to maintain one.

The real beauty of the Miata has always been it’s trouble free nature and durability.  Lots of top down smiles and a great car with low running cost.  

z31maniac
z31maniac MegaDork
8/13/18 5:27 p.m.

Why is the throttle plate thing "interesting?" The Speed 3 did this a decade ago as well as many other cars, even at full pedal extensions, at the RPMs climb, the throttle plate slowly closed. Shown multiple times with datalogging. 

Johnny2Bad
Johnny2Bad New Reader
8/13/18 5:31 p.m.

I can't say I'm totally surprised. I own an original NA (build date February 1990, 1.6 engine) and the tach will tell you you hit the rev limiter at 7200 RPM but if you put it on a dyno the actual revs are 7000. Same with the 1.8 ... advertised redline is down to 7000 and the tach will show 7000 at the rev limiter but on a dyno it's actually 6800.

The practice is quite common with OEMs actually. Good thing it's not a boat ... the speedos on those are wildly optimistic. 

Keith Tanner
Keith Tanner MegaDork
8/13/18 5:38 p.m.
z31maniac said:

Why is the throttle plate thing "interesting?" The Speed 3 did this a decade ago as well as many other cars, even at full pedal extensions, at the RPMs climb, the throttle plate slowly closed. Shown multiple times with datalogging. 

Was it interesting then? Because if so, it's still interesting now. The Speed 3 may have been doing some boost control by tapering off the throttle.

The NA was notorious for reading 300 rpm high, but only when you were accelerating hard. It would actually show you going past redline - the limiter would kick in as intended, but the tach would be ahead of it. You usually saw 7500 on the tach with the 7200 rpm limiter.

Snrub
Snrub HalfDork
8/13/18 7:44 p.m.

Sounds awesome.

It doesn't look like the power difference shows up on the simple stopped/slow to something faster test. I suspect it will show up more on acceleration from a decent speed on up. The Fiat 124's greater power under the curve only seems to show up in these circumstances as well.

Keith Tanner
Keith Tanner MegaDork
8/13/18 8:31 p.m.

On our dyno testing, the 16 and 19 are equal to 6000 rpm. Then the 16 falls off a cliff and the 19 just keeps climbing. So you have to wind it out to see the power, which won't show up on a roll-on right away. But if you like revs, it rewards. 

CyberEric
CyberEric HalfDork
8/13/18 9:16 p.m.

Man, it's tough out there on the internet.

Mazda, if you're reading this, I just want to say thank you for making the improvements to an already great driver's car. Job well done. 

Keith Tanner
Keith Tanner MegaDork
8/14/18 1:48 p.m.
Andy Hollis said:

What matters most to me is whether I can get 7500 in gears 2-4 for consistent lap behavior on the track.  Being able to continue to pull longer in 4th instead of 5th, when the car is really working hard against drag, makes a big difference.  And knowing it will be the same every lap, is also key.

Keith...if you have a 2019 at hand, do us all a favor and run it up through each gear at WOT and see where it hits the limiter, please.

We had the car on the dyno yesterday and I spent a bunch of time playing with it on the street.

I was never able to make it trigger a rev limiter at less than 7500 indicated on the tach in the first four gears. I tried both WOT and light throttle. In fourth, it felt as if the ECU was closing the throttle off as I approached 7500 on the tach - we've seen that on the dyno on other NDs. Basically, it acts as if it has a very soft rev limiter in that case. But more importantly, 100% consistency. It hasn't been on the track - yet - but I may do that tomorrow.

We did find a couple of things that we're talking to Mazda about, I'll go public with them once I have more details.

Keith Tanner
Keith Tanner MegaDork
8/14/18 1:56 p.m.

One other note about the 2019 (and the 2018s) - the car has moved from indirect TPMS to direct. I'm going to yammer on about this - but it is more important to GRM peoples than the average driving public.

Indirect TPMS means the car is not measuring tire pressure directly, but is calculating it. It was a pretty clever system, using speed variation betwen the wheels as measured by the ABS sensors. That's not new, my E39 does it. The downside is that if all of your tires are off by the same amount it can't tell. But the Mazda system also has input from the steering rack. From what I can figure, it's using steering angle to determine corner radius and thus calculating the correct wheel speed difference from one side to the other. If that's off, it'll know that multiple wheels are incorrect. The first time it popped a light after I'd installed tires with a larger OD, I couldn't believe it. You can tell the car that the larger tires are the New Normal and it'll accept that. I love it. It's taking information that's all in the network and using it. Just software, no new sensors, nothing that wears out, no problem with swapping wheels around.

Direct TPMS is like most other cars. A little expensive sensor that's mated to the car and has non-replacable batteries.

If you're swapping tires back and forth, it means you'll have to live with a TPMS warning. Not the end of the world, but it's annoying to see a permanent error light on your brand new car if you've decided to run the bronze wheels instead of the tungsten because they have more tread left...

Vigo
Vigo UltimaDork
8/14/18 4:44 p.m.

 But now the conversation has been turned from what the car is like to drive to a bunch of forums and journalists (all over the place) latching on to a sensationalist story without hard data - and dyno runs are not hard data in this case. I feel bad for the Mazda PR guys.

I agree that  it's sort of tragic, but by the same token i don't feel bad for the Mazda PR guys because all they had to do was bury one or two sentences somewhere in the press materials given at launch and this would have been avoided. Someone else referenced the RX8 hp fiasco. They should know better. 

 

Anywho, thanks for following up with a clearer picture of when it occurs. 

AnthonyGS
AnthonyGS Reader
8/14/18 7:28 p.m.
Vigo said:

 But now the conversation has been turned from what the car is like to drive to a bunch of forums and journalists (all over the place) latching on to a sensationalist story without hard data - and dyno runs are not hard data in this case. I feel bad for the Mazda PR guys.

I agree that  it's sort of tragic, but by the same token i don't feel bad for the Mazda PR guys because all they had to do was bury one or two sentences somewhere in the press materials given at launch and this would have been avoided. Someone else referenced the RX8 hp fiasco. They should know better. 

 

Anywho, thanks for following up with a clearer picture of when it occurs. 

You are making the assumption that engineers and advertising execs communicate well.  In my experience as an automotive engineer and as an engineering consultant, engineers do not communicate very well.  They told the ad guys 7,500 rpm which is technically correct, but it’s apparently not a complete answer.  For a low hourly fee, I can help Mazda fix this issue before it becomes rpmaggeddon or rpmgate.

z31maniac
z31maniac MegaDork
8/15/18 7:54 a.m.
Keith Tanner said:

One other note about the 2019 (and the 2018s) - the car has moved from indirect TPMS to direct. I'm going to yammer on about this - but it is more important to GRM peoples than the average driving public.

Indirect TPMS means the car is not measuring tire pressure directly, but is calculating it. It was a pretty clever system, using speed variation betwen the wheels as measured by the ABS sensors. That's not new, my E39 does it. The downside is that if all of your tires are off by the same amount it can't tell. But the Mazda system also has input from the steering rack. From what I can figure, it's using steering angle to determine corner radius and thus calculating the correct wheel speed difference from one side to the other. If that's off, it'll know that multiple wheels are incorrect. The first time it popped a light after I'd installed tires with a larger OD, I couldn't believe it. You can tell the car that the larger tires are the New Normal and it'll accept that. I love it. It's taking information that's all in the network and using it. Just software, no new sensors, nothing that wears out, no problem with swapping wheels around.

Direct TPMS is like most other cars. A little expensive sensor that's mated to the car and has non-replacable batteries.

If you're swapping tires back and forth, it means you'll have to live with a TPMS warning. Not the end of the world, but it's annoying to see a permanent error light on your brand new car if you've decided to run the bronze wheels instead of the tungsten because they have more tread left...

 

So I guess it's not like my 135 where I can go into the car menu and simply reset it to read new sensors?

I know on the BRZ there is an OBD-II box guys are wiring in that permanently do things like block the TPMS warning light, or always have the car in "Pedal Dance" mode.

alfadriver
alfadriver MegaDork
8/15/18 8:09 a.m.
AnthonyGS said:
Vigo said:

 But now the conversation has been turned from what the car is like to drive to a bunch of forums and journalists (all over the place) latching on to a sensationalist story without hard data - and dyno runs are not hard data in this case. I feel bad for the Mazda PR guys.

I agree that  it's sort of tragic, but by the same token i don't feel bad for the Mazda PR guys because all they had to do was bury one or two sentences somewhere in the press materials given at launch and this would have been avoided. Someone else referenced the RX8 hp fiasco. They should know better. 

 

Anywho, thanks for following up with a clearer picture of when it occurs. 

You are making the assumption that engineers and advertising execs communicate well.  In my experience as an automotive engineer and as an engineering consultant, engineers do not communicate very well.  They told the ad guys 7,500 rpm which is technically correct, but it’s apparently not a complete answer.  For a low hourly fee, I can help Mazda fix this issue before it becomes rpmaggeddon or rpmgate.

Except that you know that there are many reasons limits are set.  So just raising the global engine limit to 7500rpm may not be the best idea in the world.  Or could be a really bad idea, too.

There are a TON of limits in powertrains, for various reasons.  This group should be aware of why they are there before demanding that they be turned off or bypassed.  There are cost consequences for anyone of those limits being raised.  

Keith Tanner
Keith Tanner MegaDork
8/15/18 10:06 a.m.
z31maniac said:
Keith Tanner said:

One other note about the 2019 (and the 2018s) - the car has moved from indirect TPMS to direct. I'm going to yammer on about this - but it is more important to GRM peoples than the average driving public.

Indirect TPMS means the car is not measuring tire pressure directly, but is calculating it. It was a pretty clever system, using speed variation betwen the wheels as measured by the ABS sensors. That's not new, my E39 does it. The downside is that if all of your tires are off by the same amount it can't tell. But the Mazda system also has input from the steering rack. From what I can figure, it's using steering angle to determine corner radius and thus calculating the correct wheel speed difference from one side to the other. If that's off, it'll know that multiple wheels are incorrect. The first time it popped a light after I'd installed tires with a larger OD, I couldn't believe it. You can tell the car that the larger tires are the New Normal and it'll accept that. I love it. It's taking information that's all in the network and using it. Just software, no new sensors, nothing that wears out, no problem with swapping wheels around.

Direct TPMS is like most other cars. A little expensive sensor that's mated to the car and has non-replacable batteries.

If you're swapping tires back and forth, it means you'll have to live with a TPMS warning. Not the end of the world, but it's annoying to see a permanent error light on your brand new car if you've decided to run the bronze wheels instead of the tungsten because they have more tread left...

 

So I guess it's not like my 135 where I can go into the car menu and simply reset it to read new sensors?

I know on the BRZ there is an OBD-II box guys are wiring in that permanently do things like block the TPMS warning light, or always have the car in "Pedal Dance" mode.

Okay, I checked the procedure. It's like my Dodge, it'll automatically register the new wheel units within 10 minutes of driving over 16 mph. So it's not difficult to do, but it does increase the cost of each set of wheels and tires by $200. It doesn't give you actual pressures or which corner is low, so it brings no actual benefits to the driver over the indirect version. It just costs more. Interestingly, it was not added to all trim levels in 2018, only some.

Driven5
Driven5 SuperDork
8/15/18 10:14 a.m.

In reply to Keith Tanner :

Since it couldn't have been bean counters, perhaps it was lawyers...Afraid of liability from the 'dreaded' four-tire-synchronized-leak. LOL

Keith Tanner
Keith Tanner MegaDork
8/15/18 10:16 a.m.

It was obviously lawyers or legislators. The car can already catch a four tire leak - or, more realistically, a change in temperature - with the indirect system so that's not the reason.

Keith Tanner
Keith Tanner MegaDork
8/15/18 10:44 a.m.

More driving impressions.

The level of polish in the controls and calibration is fantasic. Tip-in is very well done and the car seems to be stronger at part throttle than earlier ones - that doesn't show in a dyno. Oddly, I find the car very easy to launch from a start - not a drag launch, just a street launch. I never had a problem before, but the 2019 is really, really good.

The screen that everyone loves to hate until they drive the car has improved sharpness and contrast.

Joe Gearin
Joe Gearin Associate Publisher
8/15/18 11:42 a.m.

I've driven the ND1 and yes, I still hate that ugly screen jutting out from the dash.  Good to hear it's clearer now...I suppose. 

 

 Now if they can just do something about that stupid volume control right where my forearm wants to be.....they'd have about a perfect car.  Well, the trunk is too small on the ND too (smaller than even an NA) .....but driving wise, it's pretty spectacular.  

miatafan
miatafan New Reader
8/15/18 11:51 a.m.
AnthonyGS said:
Vigo said:

 But now the conversation has been turned from what the car is like to drive to a bunch of forums and journalists (all over the place) latching on to a sensationalist story without hard data - and dyno runs are not hard data in this case. I feel bad for the Mazda PR guys.

I agree that  it's sort of tragic, but by the same token i don't feel bad for the Mazda PR guys because all they had to do was bury one or two sentences somewhere in the press materials given at launch and this would have been avoided. Someone else referenced the RX8 hp fiasco. They should know better. 

 

Anywho, thanks for following up with a clearer picture of when it occurs. 

You are making the assumption that engineers and advertising execs communicate well.  In my experience as an automotive engineer and as an engineering consultant, engineers do not communicate very well.  They told the ad guys 7,500 rpm which is technically correct, but it’s apparently not a complete answer.  For a low hourly fee, I can help Mazda fix this issue before it becomes rpmaggeddon or rpmgate.

This makes me think back to the scandal about the HP on the RX-8 and the fact that it would only make the advertised HP when on a rolling road dyno.

 

Driven5
Driven5 SuperDork
8/15/18 12:01 p.m.
Keith Tanner said:

It was obviously lawyers or legislators. The car can already catch a four tire leak - or, more realistically, a change in temperature - with the indirect system so that's not the reason.

Ok, apparently I didn't fully grasp that part of your description...In that case:

Vigo
Vigo UltimaDork
8/15/18 1:15 p.m.

Except that you know that there are many reasons limits are set.  So just raising the global engine limit to 7500rpm may not be the best idea in the world.  Or could be a really bad idea, too.

If it only makes the claimed power bump under special sauce circumstances, people will rightly complain. If it makes the stated power gain at basically all times i think it will eventually become a non-issue regardless of under what conditions it hits 7500rpm. 

alfadriver
alfadriver MegaDork
8/15/18 2:58 p.m.
Vigo said:

Except that you know that there are many reasons limits are set.  So just raising the global engine limit to 7500rpm may not be the best idea in the world.  Or could be a really bad idea, too.

If it only makes the claimed power bump under special sauce circumstances, people will rightly complain. If it makes the stated power gain at basically all times i think it will eventually become a non-issue regardless of under what conditions it hits 7500rpm. 

The power peak is below 7200, so having a gear specific engine speed limit between 7200 and 7500 should not change that..  At least according to the data I've seen (including Kieth's data).

Keith Tanner
Keith Tanner MegaDork
8/15/18 3:04 p.m.

Alfa, I'd love to ride along with you in both the ND1 and the ND2 and hear your comments on the calibration. It's really good. They also played some games with injector staging (3 stage instead of 2) and the combustion chamber swirl that you'd have interesting insights on.

alfadriver
alfadriver MegaDork
8/15/18 4:02 p.m.

In reply to Keith Tanner :

That would be fun AND interesting.  

Is the engine PF and DI, or just DI?  As the CFD models get better, the more interesting injection strategies you will see- 3, 4, and 5 injections for the most stable and clean start.  All the better for both emissions fuel economy- since you can run the engine at peak efficiency much faster.  And the industry learns more and more what kind of turbulence works better.  IMHO, there will be more engines changes like this one- where power improves (which is more air flow at the top end, which isn't that easy) and still the right turbulence to get the best burn rate for efficiency and cleanliness.  It's one of the reasons I don't see the death of the ICE in the near future as many others do.

Much of this can also be seen in the current Toyota 2.5l that really woke up the industry.  

Keith Tanner
Keith Tanner MegaDork
8/15/18 5:42 p.m.

DI only.

The previous engine wasn't exactly a dinosaur, but they did manage to improve it all the way around with both old-school stuff (cams, porting) and some reprogramming. Some guy named "Tom Suddard" (like that's a real name) uploaded a Mazda PDF full of pretty pictures that's a good read. The combustion chamber flow CFD looks like what I remember you saying about the Toyota engine.

https://www.dropbox.com/s/7c6tczlh6mvwjc2/19MY%20MX-5%20SLP%20PRESO%20-%20FINAL.pdf?dl=0

alfadriver
alfadriver MegaDork
8/15/18 5:53 p.m.

In reply to Keith Tanner :

That is an interesting document.  Their triple injection isn't what I was thinking about- most everyone does it to get the catalyst lit off really quickly.  What their press release is doing addresses an area that DI engines have had a different problem with- pre-ignition- so bad that you can quickly grenade a motor.  And everything thing I've seen about it suggests that it's very much related to particulates.  Doing triple injection at high load, low speed should reduce that.

And some of the smoothness you feel is that even combustion.  Instead of wavering on the edge of knock, perhaps pulling spark out here and there, and having some questionable combustion, the triple injection should allow better spark, and much smoother torque delivery.  Pretty cool.

Our Preferred Partners
q7bh56GKssBTELJBM0raNbprdGWr6IqgVDHl40nWFJiFdfgSSVR2xqZ98PgrVB1l