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.
Photography Credit: David S. Wallens
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.”
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.
“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.
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.
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.
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.
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.
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.....
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.
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.
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.
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.
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.
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