Mazda's new engine boosts fuel efficiency by 30%

:
2016 CX-5 AWD Touring
For us in the states, 30 km/liter = 70.56 mpg. Taking into account yrwei52's experience, I'd say about 60mpg, not too bad :)


http://asia.nikkei.com/Business/Companies/Mazda-s-new-engine-boosts-fuel-efficiency-by-30

Mazda's new engine boosts fuel efficiency by 30%

Automaker plans to offer cars with the new technology next year

TOKYO -- Japanese automaker Mazda Motor will introduce a new engine at the end of 2018 that offers 30% better fuel efficiency by using pressure, not spark plugs, to ignite fuel.

This will be the first practical application of the technology, called homogeneous charge compression ignition. Though the automaker is developing environmentally friendly electric vehicles, Mazda thinks the internal combustion engine will continue to account for the majority of new-vehicle sales for the foreseeable future and that the company's technology will give it a leg up on the competition.

Mazda plans to incorporate the new engine in 2018 in the new Mazda3, dubbed Axela in Japan, which will undergo its first overhaul in five years. The engine then will be adopted gradually by other models. The automaker positions the engine as the second generation of its Skyactiv suite of environmentally friendly technologies, which were introduced in 2011.

The new engine ignites the mix of fuel and air by subjecting them to pressure, making combustion more efficient than conventional engines using spark plugs. This method also reduces exhaust emissions.

Varied configurations among models make simple comparisons difficult, but the new engine would give the current Mazda3 mileage approaching 30km per liter, according to estimates.

Mazda will start mass-producing electric vehicles by 2019 and plans to have a plug-in hybrid as of 2021. The automaker is targeting the U.S. and European markets, where environmental regulations are becoming stronger, but the company plans to incorporate the engine in autos built for the global market, including developing nations, by at least 2030.

(Nikkei)
 
That's for MAzda3 btw.

Lifetime mpg monitor has not been touched in CX-5 for the last 40k miles. Averaging 30mpg and no hypermiling needed. Gotta love the 2.0 engine. I think I'll hold out for skyactiv 3 :).
 
By the time 2030 rolls around we will see hydrogen or battery powered or some other texh cars ruling the road
 
By the time 2030 rolls around we will see hydrogen or battery powered or some other texh cars ruling the road

I think that was a typo. Looks like it's supposed to be released in 2018 and Mazda probably expects to sell it until at least 2030 in developing countries where they expect hybrid/electric cars will be adopted more slowly than europe/japan
 
By the time 2030 rolls around we will see hydrogen or battery powered or some other texh cars ruling the road

By 2000 I thought we all would be driving in flying cars. #TheJetsonsLied
 
So, ..... How is that different from a current diesel engine? At equal compression ratios, a spark ignition engine is more efficient than a compression ignition engine.
 
So, ..... How is that different from a current diesel engine? At equal compression ratios, a spark ignition engine is more efficient than a compression ignition engine.

But diesel fuel and petrol have different properties
 
By 2000 I thought we all would be driving in flying cars. #TheJetsonsLied
So true! When we're watching《2001: A Space Odyssey》in 1968, we all thought space travel in 2001 would be the routine activity of our life ⋯ (boom08)
 
So true! When we're watching《2001: A Space Odyssey》in 1968, we all thought space travel in 2001 would be the routine activity of our life ⋯ (boom08)

Instead we have bathrooms for he-shes and a gorilla getting gunned down spawned an internet movement and both candidates for president used Twitter and Facebook as major campaigning resources. The guy who won has assured us his dick isn't small, and the woman who lost has convinced many people that the release of her e-mails is more wrong than the crimes explained in them. If I had been alive in 1968 and seen the high hopes we held back then I'd drink bleach today.
 
So, ..... How is that different from a current diesel engine? At equal compression ratios, a spark ignition engine is more efficient than a compression ignition engine.

Good question which is above my understanding. Perhaps the elimination of the spark plugs helps to allow for the higher compression ratio. A lot is said about the improved mpgs. Now will the higher compression ratios also net greater HP/TQ?
 
Current skyactiv1 compression ratio is NON-US 14:1, (US 13:1) by comparison the skyactiv2 engines with the HCCI ( homogenous charge compression ignition ) are 18:1 compression.

The hurdles to overcome are low octane gas in the US, and the RPM range of a HCCI engine, as it needs a narrow RPM range to work with enough heat, and prevent misfires.

I predict we will see a "Premium Fuel Required" on the skyactiv2 engines
 
Last edited:
But diesel fuel and petrol have different properties

You mean diesel has higher viscosity, lower vapor pressure and lower energy content (19,300 BTU/lb HHV) vs gasoline (20,400 BTU/lb HHV)? :)
http://www.engineeringtoolbox.com/fuels-higher-calorific-values-d_169.html

Good question which is above my understanding. Perhaps the elimination of the spark plugs helps to allow for the higher compression ratio. A lot is said about the improved mpgs. Now will the higher compression ratios also net greater HP/TQ?

Higher compression does increase HP, torque, fuel economy (hotter combustion burns more completely) and NOx emissions (from hotter combustion temps), as long as the fuel doesn't detonate. Direct injection can help by timing the fuel delivery. Diesel has much better detonation resistance than gasoline. Spark plugs don't affect detonation, they time the start of combustion relative to piston position. That's harder with a diesel engine, but you get some timing control with injection timing, not sure how much.
 
With the temp here in Minnesota reaching -10*F last week, and normally is around 10-20*F in winter, I'm really curious to see how Mazda engineers overcome the cold start with HCCI.
 
This site indicates for every "1" compression increase, HP also increases 4%. So increasing to 18:1 means aprox a 30hp increase or 215HP.
http://dsportmag.com/the-tech/boost...igh-boost-levels-and-high-compression-ratios/

I think it's more complex than that, as you need to take valve overlap and cam timing and the like into account, too, but that does sound "about right" to me.

I just wonder what kind of a beast of a starter that thing is going to require! Or if it will use an initial spark to kick it off or something.
 
I think it's more complex than that, as you need to take valve overlap and cam timing and the like into account, too, but that does sound "about right" to me.

I just wonder what kind of a beast of a starter that thing is going to require! Or if it will use an initial spark to kick it off or something.

Yeah..maybe a combination of some alternately generated spark and the use of i-stop?
 
So if increasing compression makes for more power why did Mazda reduce the compression ratio for the diesel?

Although they did increase the ratio for the petrol. Can someone explain.
 
Back