The next-gen MX-5 Miata thread

[homeforsummer]

Me neither. And can anyone explain the "cleaner" part?

More economical engine, fewer materials used in construction = cleaner.

I don't see 800kg as being unobtainable with modern construction techniques and the fact it'll be using a smaller engine. The SkyActive engines are supposed to be quite lightweight as far as I'm aware and taking weight out of the engine compartment is a pretty easy way of reducing weight overall. Careful use of steel thicknesses, use of other lightweight materials, light road wheels, lightweight seats, a physically smaller body and other things and it's not too hard to see where the weight might go.

 

[Kent]

Im doubting significant loss of weight. A while back the mx5 showed prowess as an mrs beater but lately the cars seems to struggle compaed to competition from the likes of cars like the solstice.
If mazda puts effort into a new miata like they have with the ms3 they should be fine, if the rx8 team handles the new miata Id expect to see other companies looking better in the FR coupe segment.
With the frs on the way Im going to have a close eye on what mazda does here and Im hoping for the best.

 

[CodeRedR51]

I'm trying to figure out the time frame here. It's been 6 years since the NC has been released to the public, so they should be getting pretty close on debuting a concept car of some sort within the next year or so. 2011 Tokyo Motor Show?

 

[Moot]

If they get it to 800kgs, then it won't even need a 1.4 turbo, a 1.0 turbo with 115bhp would do. And it would nearly be as quick as the original Lotus Elise, which would be amazing. A 1.4 turbo high bhp engine would put it into super-car territory.

 

[CodeRedR51]

If they get it to 800kgs, then it won't even need a 1.4 turbo, a 1.0 turbo with 115bhp would do. And it would nearly be as quick as the original Lotus Elise, which would be amazing. A 1.4 turbo high bhp engine would put it into super-car territory.

I highly doubt that.

The Flyin' Miata Westfield shop car weighs 1,200 pounds and uses a turbo 1.8 Miata motor making roughly 250hp. That might be super-car territory...

 

[Moot]

Well for example take the 6 litre V12 Aston Martin DB9 450bhp 0-60mph in 4.7 seconds.
Then take the Elise 340R with 170bhp and does 0-60mph in 4.3 seconds, it kills the Aston Martin nearly half a second quicker acceleration to 60mph.
So 170bhp beats super-cars, a 1.4 turbo would have about 170bhp depending on tune (the Alfa Mito has 170ps from it's 1.4).
So a MX5 at 800kgs and 1.4t could enter Super-car levels of acceleration, similar to an Elise 111R maybe.
Of course the acceleration comparison ends after 70mph, but that's the limit for roads anyway. And would still be great fun on a track.

 

[Robin]

Mazda are going to be hard pressed to make it any lighter seeing as the last one they only managed to shave a few grams off and it was still 9.5kg heavier, as Hammond explained in this Top Gear feature.



Although Mazda new design language looks OK on some models it looks hideous on others and I don't think the next MX-5 should have that styling.

Robin.

 

[niky]

But the new car was built for and with bigger engines, and gave a lot more performance potential.

A car built around a smaller mill should see weight savings all around... 800kg might be a stretch without fancy alloys or even aluminum body work, but they can probably do it.

 

[Jim Prower]

However, a turbo mill has a bit more weight than a N/A mill by design, due to all the cooling and turbo equipment. Main thing a small turbo mill has over a larger N/A is the fuel economy.

 

[eSZee]

If they get it to 800kgs, then it won't even need a 1.4 turbo, a 1.0 turbo with 115bhp would do. And it would nearly be as quick as the original Lotus Elise, which would be amazing. A 1.4 turbo high bhp engine would put it into super-car territory.

I would prefer a non turbo motor. What's the point of a tiny turbo when you have to beat the crap out of it to get into power and it will most likely sound awful?

Main thing a small turbo mill has over a larger N/A is the fuel economy.

I'm not sure that is the case in most situations. In japan it would be cause the speed limits are lower and people tend to drive much slower but in the US, you would have to beat the motor to get going and fuel economy would suffer.

 

[CodeRedR51]

I would prefer a non turbo motor. What's the point of a tiny turbo when you have to beat the crap out of it to get into power and it will most likely sound awful?

Turbo cars sound awful? News to me...

...but in the US, you would have to beat the motor to get going and fuel economy would suffer.

That's something I really hate about people now days. Everyone has to drag race away from a green light or do 80 on the freeway. The general population complains that they want better fuel economy, but what they really need is an education on how to lift their lead foot.

 

[eSZee]

Turbo cars sound awful? News to me...




That's something I really hate about people now days. Everyone has to drag race away from a green light or do 80 on the freeway. The general population complains that they want better fuel economy, but what they really need is an education on how to lift their lead foot.

The engine will sound awful cause it will sound thrashy and be noisy. I didn't say turbo engine sound bad.
I hate that too, but if they make the turbo very peaky, you'll be struggling to keep up with he average drivers.

 

[Keef]

You do realize that with modern computer-controlled timing and direct injection and all those goodies, the days of the "peaky" turbo are pretty much over. These days peak torque comes on at 1500 and literally stays there until 5. That was unheard of 10 years ago.

 

[NLxAROSA]

and all those goodies

Twin scroll and variable geometry mostly. Especially that last one ensures you have maximum torque over a huge range.

 

[JJ72]

This is one of those questions that I fail to see why it's so hard to answer. If you throw more features on a car, it's going to get heavier. If you use more exotic materials, it's going to get more expensive. However, if you take a little more time with your engineering and try to eliminate redundant components and try to get things to serve multiple functions, you start losing weight really fast, really inexpensively. Gordon Murray did this to great effect on the McLaren F1, and I expect he did it to even greater effect on the T25. Why forethought is a foregone conclusion is beyond me.

Development cost millions though, and time. And it is just a stroke of genius to find a substantial gain without new breakthrough in material technolgy. You simply can't expect a car company to out engineer themselves on a consistent basis.

 

[homeforsummer]

The engine will sound awful cause it will sound thrashy and be noisy. I didn't say turbo engine sound bad.
I hate that too, but if they make the turbo very peaky, you'll be struggling to keep up with he average drivers.

Hmm. Generalising a bit there.

Not sure where you got "noisy" from either. Turbo motors tend to be muted a little compared to NA engines as the turbo acts a bit like a silencer, but there's no specific reason why it should sound awful. Much of the noise you hear is induction and exhaust noise and if those two are tuned right then there's no reason it can't sound great.

People have been turbocharging Mk1 MX5s for yonks. I've always liked the way the MX5's engine and exhaust sound and the turbocharged ones don't immediately sound rubbish after the conversion.

As Keef says too, it's been well over a decade since we've seen peaky turbocharged engines. Probably longer, the last production turbocharged car I can think of that was genuinely all-or-nothing was the first batch of big turbo Escort Cosworths in 1992/1993...

Development cost millions though, and time. And it is just a stroke of genius to find a substantial gain without new breakthrough in material technolgy. You simply can't expect a car company to out engineer themselves on a consistent basis.

Mazda took an easy 150kg off their last Demio/2 through clever use of materials and making it smaller, and that's just a basic small car. Get rid of two seats and be even more clever with materials and there's no reason that a new MX5 couldn't be very light indeed.

 

[Sureboss]

I quite like the idea of a 1.4 turbo'd MX-5 that weighs under a tonne. Changing to match market conditions was inevitable and gives them a chance to re-live the Mk1. Nice.

 

[eSZee]

Hmm. Generalising a bit there.

Not sure where you got "noisy" from either.

Reading magazines bashing the GM 1.4L Turbo in all the cruze reviews. It's noisy, it's slow, and the fuel economy is pathetic.
I know it's GM and they aren't known for doing good small motors but the cruze isn't an exception.

You do realize that with modern.........

Yeah, I'm aware of it. I just think Mazda should stick with a n/a motor, like they have done. I don't see them going with a small turbo and changing what they have been doing with the car so far. Small/medium displacement 4cyl with a 7000rpm+ redline and peak hp coming in right around that. Isn't that what roadsters and small sports cars have always been?

 

[DK]

^ Mazda turbo'd straight-4 =/= Chevy turbo'd straight-4

It's nice to see Mazda wanting to apply Colin Chapman's motto of "performance through light weight." And, as HFS has said, turbo'd NA-chassis MX-5s have been around almost as long as the car itself.

 

[eSZee]

You're probably right.

Let's not forget that there is ZERO material to back up this whole 1.4L TC going into the miata. It's just AB reporting what someone else said might be a possibility. Of course it's plausible cause mazda seems to be moving over to skyactive in many models, I just don't think they will.

edit
One more thing, the SkyActive engines run a pretty high CR, don't they? The 1.3 is something like 13.5-14:1. Using those in a turbo application would be a little counter productive wouldn't it? They would have to lower that quite considerably to boost the motor, right?

 

[Moot]

It will happen "at some point in the future" we can assume anyway, even if it's not the next car out...

 

[homeforsummer]

Reading magazines bashing the GM 1.4L Turbo in all the cruze reviews. It's noisy, it's slow, and the fuel economy is pathetic.
I know it's GM and they aren't known for doing good small motors but the cruze isn't an exception.

It sort of is. The vast majority of small capacity force-inducted motors offer far more economy than an NA engine of equivalent power, and much more performance than an NA engine of equivalent capacity.

As for the SkyActive compression, I'd expect that's variable depending on the unit. A turbo engine would likely be different.

 

[eSZee]

So it just comes down to americans not knowing how to build a small displacement turbo motor?
I was looking at the outline of what SkyActiv is about and what it's supposed to achieve and the only mention of a turbo is in the diesel motor.
The 14.0:1 compression ratio is a big deal to mazda and it's the bold point of the whole skyactiv system.

 

[blasos]

What's the point of a tiny turbo

Lighter engine, lower emissions, greater fuel economy and more low-end torque. Simple really.

when you have to beat the crap out of it to get into power

Not true, a turbo by nature produces more power lower in the rev-range than a normally aspirated car.

 

[Rotary Junkie]

So it just comes down to americans not knowing how to build a small displacement turbo motor?
I was looking at the outline of what SkyActiv is about and what it's supposed to achieve and the only mention of a turbo is in the diesel motor.
The 14.0:1 compression ratio is a big deal to mazda and it's the bold point of the whole skyactiv system.

14.0:1 doesn't actually mean they won't necessarily boost it. Personally I'd love to see Mazda put a very small Miller-cycle in the Miata, particularly with today's technology (direct injection mainly).

Lighter engine, lower emissions, greater fuel economy and more low-end torque. Simple really.

Not really and perhaps heavier in some cases, maybe, maybe, no.

Turbos are great for "low-end" when sized properly but they do nothing for off-idle torque.

Not true, a turbo by nature produces more power lower in the rev-range than a normally aspirated car.

Depends on a lot of factors other than turbo vs NA. And he's right; a small turbo motor will be working a LOT harder to hit the same part throttle acceleration as a larger NA engine.

 

[Keef]

Yeah, I'm aware of it. I just think Mazda should stick with a n/a motor, like they have done. I don't see them going with a small turbo and changing what they have been doing with the car so far. Small/medium displacement 4cyl with a 7000rpm+ redline and peak hp coming in right around that. Isn't that what roadsters and small sports cars have always been?

The engines in NA Miatas were fit for use in a tractor. There was absolutely nothing exceptional about them. The 1998 NB engine was like a tractor with a high-flow head, and the 2001 engine was like a tractor with variable valve timing.

Just because it's a small sports car doesn't mean it has to have a lackluster truck engine like the Miata's ancestors always had.

I think you're confusing Mazda for Toyota and Honda. Those are two companies that can make a 4-cylinder with soul when they feel like it.

 

[CodeRedR51]

Just because it's a small sports car doesn't mean it has to have a lackluster truck engine like the Miata's ancestors always had.

Truck engine? As far as I know they were created specifically for the Miata and very similar to the BP engine from the 323 GT-X and GT-R models. Not that great N/A, but a very stout Turbo motor.

 

[Keef]

A 2JZ is a stout turbo motor. The 1999 head aside, Miata engines have been exceptionally normal in factory tune, and quite cost-ineffective when trying to make power. Especially the post-2001 engines that require multi-thousand dollar engine management.

Note I never said they were bad. They're just not special.

 

[CodeRedR51]

A 2JZ is a stout turbo motor.

It's also an inline-6.

For an early 90's 4-cylinder, in my opinion, it's a stout turbo motor. Not many N/A 4-pots out there that can handle an extra 100-125hp on top of the stock number without self destructing.

 

[eSZee]

I think you're confusing Mazda for Toyota and Honda. Those are two companies that can make a 4-cylinder with soul when they feel like it.

I never said soul nor did I allude to it anywhere in my post. I said that roadsters and small sports are associated with a high revving I4. The miatas were no different. The NC peaked at 7k, didn't it?