The old thread has broken and will no longer stick! So lets start again.
Pleast post all press speculation, photo mock ups, rumours etc. relating to the next generation MX-5 in this thread.
I think the only things we know for certain so far is that Mazda are developing something jointly with Alfa which may appear in 2014.
Please have a browse through the old thread for over two years worth of speculation, guess work, opinion…
Just saw a thread on the Miata forum about a diesel engined MX5, any thoughts
http://www.motorauthority.com/news/1083921_diesel-engine-mulled-for-next-gen-mazda-mx-5-report
yeah, read the previous thread linked in Martin’s post above! 
Shame we have to kick off the new sticky with a bit of a non starter of a rumour, though there have been some real doozers over the past couple of years, which makes the thread to date quite a laugh. But a diesel is pretty unlikely.
This journadvertising hash up repeat article is even lazier internet web traffic hit building content, than the Autocar one - grasping at the popular MX-5 straws fan base to draw in folks for advertising stats… The article is contentless speculation and has little worth menitoning - its only factual points are to relate that Diesel engines have low revs and are heavier than petrol blocks! hold the front page and warm up that Pulitzer!
With the next revision probably already driving around Japan somewhere (at least in parts) we are in a weird time until the spyshots folk start to catch up with them or mazda feed a leak - but until then we are going to have to endure the ramblings of so called motoring Journalists trying to sell papers or websites and rumour masquerading as news, while we all wait to see what is going to be actually revealed.
Diesel convertibles are an abomination. Look, I cycle to work and I can tell you that diesel exhaust smells. I mean, it smells bad. You really don’t want a faceful of it when you reverse out of your driveway. I’ve been running a BMW 320d estate for the last year and, while it is undoubtedly a fine motorway cruiser with bags of mid-range acceleration, there is nothing “nice” about a diesel engine; the vibration, the noise at idle, the smell, the occasional cloud of smog when it’s been driven gently for too many miles and you boot it. I’m also not sold on the environmental benefits, since soot and NOx are pretty much the beginning and end of city pollution these days, and they all emanate from diesel engines. I’d rather have a bit more CO2 if it means air that is still breathable without causing cancer.
While not against diesel engines in principle I do agree that the current generation seem to be focussed more on economy and cheapness of build than they are on quality. I still remember the advert for the BMW 2.5 TD engine when they brought it out in the e34. They had a guy balance a 50p coin on its edge on top of the engine while it was running to demonstrate how smooth it was. Well maintained one of those engines was a delight and the driving experience was good. But fast forward to today and diesels tend to be more likely to live up to their reputation as dirty, noisy and rough.
I owned a modern turbo-diesel for 5 years. For the first 2 of those years it was my only car. I don’t recall it being noisy, nor do I recall any vibration problems. I never saw any smog, but then I didn’t let it run for miles at just above tickover.
It had the same BHP as the MX-5, but weighed a lot more, so it’s overall performance was lower. It did, however, have twice as much torque, so would pull from low revs without any drama. It did light the T/C up a few times when pulling away from a junction, but a modern MX-5 will do that too. I quite like the idea of 2x torque through the back wheels of an LSD on a light sportscar on a dry and sunny afternoon 
I think I’d miss the long rev range though.
The smell is something else though. I’ve say behind badly maintained lorries and busses with the roof down, and it’s unpleasant. But there’s a world of difference between one of those and a refined modern diesel engine.
I was following a newish Golf out of work this week and the smell was 
.
Looks as if it’s going to be a half-Alfa 1.3 turbo, anyway. The local Mazda salesman said that they hadn’t been told much technical detail about the new model but he was sure about the co-development with Alfa.
Turbos are OK if they’re water-cooled (most new petrol ones are because the exhaust temps are so high); with all that controllable boost, you can do some very interesting things with the engine mapping, like have a totally flat (and I mean flat, as in ECU-controlled, flat as a pancake) torque curve over a wide rev range. Look up the torque curve for the VW 1.4 TSI.
The only problem with a turbo comes when you arrive at a roundabout in second gear, see it’s clear, put your foot down and n-o-t-h-i-n-g h-a-p-p-e-n-s for about 2 seconds, but it feels like an age. And this is with a small modern petrol turbo. Turbodiesels retain a bit more pull when the turbo isn’t spooled up.
Mazda Press released the Alfa development on 18th January 2013 so quite rightly it should be common knowledge with their salesmen… But that is about as much as you are likely to hear - we will probably have a better handle on it in here with the input and interest of people following threads and news.
On the engine front - I’d imagine we will probably end up with a small turbo charged Ecoboost type engine probably with some form of twin-scroll turbo design to improve engine efficiency and emmissions, reduce lag and widen performance thtrough the rev range. But I’d imagine that the powerplant will me Mazda’s.
VW are again thinking about launching a Sports Car circa this time around £40k and at the moment one of the power plants under consideration is a diesel.
In the states where they do a lot of engine used oil analysis, a number of the SKYACTIV engines which have very low friction pistons and very high pressure direct fuel injection both diesel and petrol are showing in a number of cases high fuel content in the engine oil.
This tends to reduce the viscosity of the engine oil and in turn reduces the useful life of the oil so reduces the oil change interval.
Something that Mazda must be monitoring or maybe not.
It’s been well-observed that the latest Euro V diesels are likely to have expensive problems at > 3 years old (when company cars get offloaded). Diesel particulate filters and dual-mass flywheels (not all cars have the latter) are the usual culprits. Private buyers are increasingly advised to go for a petrol car unless they do absolutely huge mileages. Having said that, a petrol car with a turbo and direct injection (GDI) has a lot more to go wrong than any MX-5 to date. Fortunately petrol turbos are usually water-cooled now (diesel ones often aren’t and you can still carbonise the oil after switching off) and GDI hasn’t thrown up many serious problems yet. GDI and supermarket fuel seems risky though.
What’s the latest thinking on the date for the mk4 release?
I am contemplating a new car and want to get one before the mandatory GPS trackers are fitted in 2015 (thanks to the evil EU) in all new cars.
The Alfa version is sometime in 2015 but it has a different engine and panels.
That would suggest that at best it would be some time in late 2014 for the MK4.
Usually they stop production in car factories in late summer and that particular line is modified to manufacture the new car. Therefore a possible launch in say September or October. So no real numbers of cars available until late spring 2015.
what is the issue with a dual mass flywheel? I have one in my Corsa sxi+ cdti 1.3 turbo diesel which I use for teaching young uns to drive in…So I think you can say the car has had a “hard” life, the clutch/flywheel had to be replaced at 166,000 miles, which I think is not bad considering the life the car has had, with some 100 different people at least driving it. The fact the clutch lasted that long is good in my opinion
I often hear BMW diesels, and they are very smooth/quiet compared to the little lump in my corsa. Diesels have come on a massive amount in the last 20 years. Only a badly maintained, and poorly driven one is dirty these days, and would fail an MOT if it were. I have a V70 2.5 turbo diesel as a “family” runner, it does excess of 45 MPG on a run, has 142k on the clock, MOT a couple of weeks ago…passed no advisories…great
Both my diesels do exactly what they say on the tin, and I’m happy with them, but I doubt I would want one in an MX5, when I get into my “toy” I find it very different to the “thrum” of the oil burners, it is a load quieter at tick over, but with a roof off on a diesel?..who would want that?
On some cars the DMFs come apart (the rubber bit in the middle fails) which gives very rough running and poor performance. It’s obviously an expensive fix because the gearbox and clutch have to come off (worse on a FWD car because the driveshaft can’t simply be unbolted) and the DMF itself is not cheap.
Some people replace them with solid flywheels; there’s a little industry being created.
I have plenty of experience in regards to DMF’s failing mine did!
Not driven excessively hard or badly but still failed at 46,000 miles, or one side was going should I say.
The replacement was £300, I had the clutch done at £230, labour well £550 - lucky for me the car had a 4th year warranty I only picked up the clutch bill. I know the issue as I actually had a good relationship with the former Volvo dealership person handling warranty issues and got to see the car in person.
His view on DMF’s - “An over engineered piece of crap”.
He was saying that my car was one of two the other being Jaguar in around the same period. The most expensive DMF they handled £600.
Majority of them failed in regards to one side failing generally the one going against the motion of drive majority of the time, the other side then attempts to compensate in the process the whole thing fails.
Hi
Personally I hope they stay with a normally aspirated petrol engine. Throttle response is a rapidly disappearing positive trait in cars.
Trouble is that is twice the torque at half the rpm, so you need twice as high gearing to get it at the same road speed. Which halves the torque at the wheels, wiping out the benefit.
The number of times each day I see a diesel move off and throwing out a large amount of smoke out of the back puts me off them (well, puts me off them even more, I don’t like the power delivery with torque dropping off rapidly). Presume it is part of the emissions fiddle as with careful driving (as on an emissions test when homologating new cars) they can easily avoid the belching smoke when it might fail the emissions test.
All the best
Keith
I’ve often wondered about the effect of a nice torquey mid-range diesel engine in my MK3, esp.overtaking from about 35-40mph upwards on a twisty road … (I have been out-done many times by turboed diesels in Golfs, Astra twin-tops etc.)
Plus of course the potential for long-distance, economical cruising. Would need a bit more sound insulation though…
As far as the black smoke is concerned this is often, I beleive, the system de-coking itself after a bit of around-town use where the exhaust doesn’t get very hot …
So a tie up with Alfa, that will solve the tin worm problems! NOT.
You get the same problem on long motorway runs. The reason why diesel engines are so fuel efficient (or so it was explained to me by my mechanic) is that when not under load they lean off the mixture, but that does cause soot build-up which in turn starts to impact the economy. I do a 200 mile round-trip twice a week and I was advised to boot it when given the opportunity. The result of flooring it and running it up the revs in 3rd a couple of times each way was an increase in MPG of over 10%. You do get a hefty cloud of ‘smoke’ out the back though after an hour of motorway cruising.