2004 to 2020 Mazda 3 Forum and Mazdaspeed 3 Forums banner
1 - 11 of 11 Posts

·
Super Moderator
Joined
·
6,410 Posts
Discussion Starter · #1 · (Edited)
Well, so while everyone has been busy discussing the merits of the new Skyactiv-X engine, Mazda has been quietly making an all new 181 hp 2.0 SA-G motor that debuts in the 2019 MX-5. It been speculated about for a bit now elsewhere, Mazda made it official a few days ago. The cars are arriving right now in the California port facilities.....:smile2:
I wonder how much of this will trickle into the Mazda 3, and how much of the new motor is cross compatible with the earlier version?
Did I mention the 7500 rpm red line?:biggrin:
 

·
Registered
Joined
·
3,166 Posts
There are some tweaks internally.
Road&Track says of the updated ND:

"First modification to support the engine spinning so much higher is an increase in the rate of the valve springs to provide more tension. The pistons have also been lightened by 27 grams by shaving down the dome and getting the valve reliefs as close to the edges of the piston skirts as possible.

The connecting rods get a similar treatment, losing 41 grams of weight due to a more compact shape along with bolts that are shorter and thinner. The crankshaft gets some optimization in the form of how the counterweights are arranged. The changes continue on with the throttle body which sees its opening increased by 28 percent in order to provide more air to the engine. The airflow changes continue down towards the valve with improvement in tumble flow and an increased valve diameter.

The updates in the pistons allow for the increase of air and fuel to be safely combusted as the new design is optimized to prevent knock while maximizing thermal efficiency and minimizing emissions. The combusted mixture exits the engine through a new larger exhaust valve and a new exhaust manifold with larger runners.
All of this newfound power is transferred to the transmission through a new low-inertia dual mass flywheel which is intended to absorb noise and vibrations so that they don’t transfer to the cabin. The performance changes are rounded out with a new muffler which has been updated to reduce high frequency noise and work better with the increased redline.

Hashimoto Yohei of*Car Watch*states the changes in the exhaust are apparent as soon as the car is started describes the pull to 7500 RPM as exhilarating. He also states that the new redline allows the car to be wound out a bit more. That prevents upshifts that would have been required in the past and the Miata gets up to speed more quickly.

The rest of the changes involve some new interior and exterior colors (as well as the absence of the ugly LED running lights) along with the addition of safety equipment which expands features like Smart City Brake Support to the roadster. The last category which they cover is a telescoping steering wheel, a first for any Miata. This will surely be an exciting development for those of us that are on the taller side. The author states that he was able to comfortably slide down further in the seat since the wheel can telescope in by 30 millimeters now."

Sent from my SM-G950F using Tapatalk
 

·
Super Moderator
Joined
·
6,410 Posts
Discussion Starter · #4 ·
There was a leaked list of engine changes posted a couple weeks ago but it was taken down almost immediately. Lots more than just a couple minor changes. Almost everything that matters was tweaked - new intake design, new cylinder head design, new valves, pistons, crank and rods, new exhaust etc.
Saw a couple pictures too. The new pistons and rods looked about half the size of the old ones.
 

·
Registered
Joined
·
606 Posts
Here are the changes for the revised 2.0 engine according to Mazda.
 

Attachments

·
Awesome Member
Joined
·
41 Posts
Interesting that larger throttle body, larger exhaust manifold (ambiguous wording, but could mean larger diameter exhaust piping), and a less restrictive catalytic converter are part of the physical power plant upgrades. Seems to suggest that those items may yield meaningful gains for the current generation Sky-G. Let’s hope that the aftermarket manufacturers are taking note.
 

·
Registered
2018 Mazda 3 GT
Joined
·
2,499 Posts
Yeah..just redo everything..
CK
 

·
Registered
Joined
·
606 Posts
From what I've seen so far, the skyactiv-x engine will make its way into the 3 soon on the gen 4 body. This upgraded 2.0 skyactiv engine was designed specifically for the Miata. It suits the Miata's character when considering the extra top end power and rev limiter extended to 7500 rpm to enhance track capabilities. The Mazda 3, 6, cx3, cx5 etc. engines are designed mainly for daily driving, low-end torque, and fuel efficiency which is what the skyactiv-x will deliver.

This tweaked 2.0 will have ported heads, a wider throttle body, upgraded intake and exhausts cams and a new intake manifold. There has been a lot of talk on the Miata forums about swapping just the head, as the current head has small intake and exhaust ports to maximize low end torque. This limits top end power during high octane NA tuning and boost. Those lightened pistons may be great for higher rpm in NA, but could be weaker for boost. A number or Miata FI kits are already out (turbosource, AVO, BBR, edelbrock supercharger). Will be interesting to see how they hold up with boost.
 

·
Registered
Joined
·
660 Posts
I'd bet this will stick to being an MX-5 exclusive spec at least in the states, especially with Skyactiv-x on the way for the 3 and presumably the rest of mainstream lineup over time.
 

·
Registered
Joined
·
182 Posts
Man this will make the miata poop on the BRZ I bet. Might have to switch in a couple years. But I definitely won't jump in straight away and be the guinea pig proving this engine on the track.

BRZ appealed to me because it had relatively over built internals for the modest 200hp it made and had direct and port injection. And of course the practicality of fitting 4 wheels in the back seat, but that's another discussion.

But miata reliability with 180hp, I'm down for that if they can prove it in 3-5 years.
 
1 - 11 of 11 Posts
Top