Topic: Mazda to put 2.5-liter turbo engine in other models

[rrocket]

Presumably, the more boost required, the larger the parasitic losses.  It may be quite small, and certainly set-off by the increased efficiency of the compression cycle generally.

Remember, they are estimating, even WITH the 'supercharger', something like 20% more power with concomitant fuel efficiency gains.

Presumably, adding more boost would require more fuel burned.  Perhaps it can be scaled up with a larger supercharger, but the SpCCI tech is complicated enough to control.  Maybe in Skyactiv-X v2.0?

Merely adding a supercharger to a car requires more fuel...because of the parasitic losses. On a small 4 banger, losses would be in the order of 25hp or more. So you'd need additional fuel to compensate for that...right off the top.

And more boost doesn't increase losses....It's merely a different pulley....and the difference between a pulley that makes 5psi vs say...8psi isn't huge.

It's still stupid to ignore making power with this..you've already got the weight, losses, complexity and cost added. Make some boost ffs.

[Noto]

We don't know the size of the supercharger or any other aspect of it. Perhaps Mazda is making more power with it... Time will tell

[Seafoam]

From the picture of the skyactiv x engine the supercharger doesn't look very big.
I know the m45 i had on my 2nd generation miata was bigger than that. From memory I think it added about 40 wheel horsepower
to my car. You definitely could  feel the difference from stock.

[rrocket]

From the picture of the skyactiv x engine the supercharger doesn't look very big.
I know the m45 i had on my 2nd generation miata was bigger than that. From memory I think it added about 40 wheel horsepower
to my car. You definitely could  feel the difference from stock.

Big or small, it still uses hp to spin.

Even a water pump takes about 10hp to spin.

[Seafoam]

From the picture of the skyactiv x engine the supercharger doesn't look very big.
I know the m45 i had on my 2nd generation miata was bigger than that. From memory I think it added about 40 wheel horsepower
to my car. You definitely could  feel the difference from stock.

Big or small, it still uses hp to spin.

Even a water pump takes about 10hp to spin.

Yeah I agree . Just commenting on the size.
Anything run off a belt from the engine will create a loss to a certain extent.
Even if you tie back the bypass valve and not making boost there is a loss because the belt is still hooked up.
I guess we will have to see how it functions when mazda introduces this engine.

[Noto]

Ok, I accept that the 'supercharger' takes hp to spin.

Your argument, Ron, is that Mazda should up (maximize?  correct me if I'm misunderstanding) the boost to get more power out of the 2.0L because it already has a supercharger attached?

The current 2.0L Skyactiv-G makes a published 155hp at the crank.  Mazda has cited the 2.0L Sky-X to be estimated at ~180hp while significantly beating the Sky-G's fuel economy.

I don't see how your argument is that Mazda should therefore increase power further.  Doing so inevitably will reduce fuel economy, which was the purpose of Sky-X.  That power is increased is a good sign - the Prius, for example, lost power in its latest iteration.

So your argument is that you want MOAR POWAH (which, we all, always do)...but you seem to be taking this further and suggesting that

So it's stupid not to have it making even minimal boost to increase power.

It is making 7.0psi of boost, which does still allow for increased power over the Sky-G. 

The Sky-X is complicated enough as it is to maintain a homogeneous charge at all RPMs.  I don't think it's quite as simple as suggesting that increasing boost and squirting a bit more fuel inside would result in the power levels you deem reasonable.  I think a base Mazda 3 with ~180hp would be more than "reasonable" power.

[rrocket]

I maintain that increasing boost minimally (mechanically, it would only require a different sized pulley), the engine would make more power but still be able to beat the fuel economy of the outgoing engine...since the claim is a "significant" increase in economy.

So let's say the engine at 180hp and 7psi makes nearly 50mpg highway. It will make nearly the same 50mpg at 195hp (and say 9psi boost) in steady state driving because the pulley is decoupled. In effect, a supercharger with the ability to decouple functions in much the same way as a turbo, in that it only makes power under positive vacuum. It wouldn't matter if you're making 1psi or 100...pulley is decoupled.

You'd only see the extra power when you're flooring it...a point when fuel economy matters little.

[Noto]

I agree with your conclusion, but question the premise.

Is it in Mazda's best interests for its least-powerful car to have 195hp at the expense of having the "most" efficient engine in its class?

The supercharger is decoupled at lower engine speeds, and engages at higher RPMs.  I suspect you wouldn't get the "same" power output if the boost were increased to 9psi, or whatever.

...but I lack any technical knowledge to respond more thoroughly than that.  I would love to see a 200hp Mazda 3 that sips back in the 40mpg range, but I accept that 180 is good enough (should be a ~7s 0-100km/h runner) while still matching or beating the Corolla LE ECO's frugality at despite 40-50 more hp and torques.

[rrocket]

...but I lack any technical knowledge to respond more thoroughly than that.

That's the problem here.

You can't make any sense of what I'm saying due to the lack of your technical knowledge.

Not your fault.

[Noto]

Yup - and I accept that.

...in which case, I will defer to your expertise and join the angry mob.

[BWII]

Unless I missed it - no talk of AWD here yet??
https://jalopnik.com/the-feds-may-have-just-confirmed-a-2018-mazda6-with-all-1821943443

[OliverD]

That could just be a typo.

[Noto]

If true, I may actually buy one.  I can get good deals on Mazdas generally through a connection, and my wife was pretty much frothing at the loins when I drove up in Ithaca in a red, rental Mazda 6.  Give me turbo powah and AWD?  Yeah, I'd actually really consider that.

[Solstice2006]

When I was in the dealership last month to do my lease buyout, we were talking about the 6.  Dealerships are pretty sure AWD is coming to the 6, they are just not sure if it will come at the same time as the FWD with turbo. 

[Weels]

When I was in the dealership last month to do my lease buyout, we were talking about the 6.  Dealerships are pretty sure AWD is coming to the 6, they are just not sure if it will come at the same time as the FWD with turbo.

I got the same message last year when CX-5 shopping...  the diesel is coming....

[Noto]

And then SpCCI?

Go Mazda Go!

[Solstice2006]

When I was in the dealership last month to do my lease buyout, we were talking about the 6.  Dealerships are pretty sure AWD is coming to the 6, they are just not sure if it will come at the same time as the FWD with turbo.

I got the same message last year when CX-5 shopping...  the diesel is coming....

come on, thats different. it does exist.  it just may not meet our emissions.

[rrocket]

When I was in the dealership last month to do my lease buyout, we were talking about the 6.  Dealerships are pretty sure AWD is coming to the 6, they are just not sure if it will come at the same time as the FWD with turbo.

I got the same message last year when CX-5 shopping...  the diesel is coming....

come on, thats different. it does exist.  it just may not meet our emissions.

They've been teasing the diesel for NA for ~5+ years now.....

[Solstice2006]

When I was in the dealership last month to do my lease buyout, we were talking about the 6.  Dealerships are pretty sure AWD is coming to the 6, they are just not sure if it will come at the same time as the FWD with turbo.

I got the same message last year when CX-5 shopping...  the diesel is coming....

come on, thats different. it does exist.  it just may not meet our emissions.

They've been teasing the diesel for NA for ~5+ years now.....

I know.  But it's different.  They already have AWD vehicles here, it's not very difficult to do.   So when they saw AWD is coming to the 6, I believe it.

[EV-Light]

When I was in the dealership last month to do my lease buyout, we were talking about the 6.  Dealerships are pretty sure AWD is coming to the 6, they are just not sure if it will come at the same time as the FWD with turbo.

I got the same message last year when CX-5 shopping...  the diesel is coming....

come on, thats different. it does exist.  it just may not meet our emissions.

They've been teasing the diesel for NA for ~5+ years now.....

I know.  But it's different.  They already have AWD vehicles here, it's not very difficult to do.   So when they saw AWD is coming to the 6, I believe it.

yeah...in about 5 years or so LOL