How come they don't put a rotary engine in the Miata? It would seem a great fit, and since they're already put all the money and effort into designing the renesis... It's not that I want one, it just seems curious to me.

Discuss amongst yourselves.

Krankor
05 Shinka 6MT

 

Because of costs? The Renesis is assembled by a bunch of experienced technicians. If Mazda did offer the MX-5 with a rotary motor, the plant probably wouldn't be able to assemble/produce enough motors to keep up with the demand.

 

yep, most likely cost related issue, they want mx5 to be priced compeitively.

 

theres a conversion kit out there to make your miata a rotary... do a search, it's there

 

Yeah, this topic comes up a lot. Short answer IMHO: because Mazda is dumb.

The Renesis in the NC would be faster than an s2000 and actually practical to do. The NA chassis (and thus the NB) was designed to make a rotary swap difficult due to the location of the k-member and firewall. Yeah, there's a kit, but its still a reasonably difficult swap. Mazda is probably at the point where they will need to consider another rotary engine plant if they plan to offer more than 1 car with the Renesis engine, unless they stop 8 production, which I wouldn't expect.

 

Because they are waiting for me to do it in an NC chassis (Third gen MX-5).
Paul.

 

If they do that, you might as well forget about a new RX-7...unless they de-tuned it significantly. Coupes with rotary engines shouldn't be mx-5's, but should be an RX something.

 

18mpg

 

I would take a rotary Miata over my S2000 any day. However, that car would trounce the rx8 in every performance aspect, and in turn become the flagship. It seems nice from a performance standpoint, but MPG will suffer greatly, and change whole concept of a long time successful Miata. Calling it a risk would be an understatement. I do think it will fit well, and would have been a better way to bring back the rotary. I think a Mazdaspeed Miata should come with a rotary, and be called something other then the MX-5. I see that engine as the perfect fit for a Miata, but I guess an RX8 convertible will happen before that does. Imagine an RX8 minus 500+lbs. WOW. No more bashing on sub par performance that's for sure.

 

I was hoping with the platform sharing between the NC and the 8 that a swap would be easier, but Sport Compact Car had a chance to test the NC, they found that the NC's front subframe will have issues with the Renesis due to the fact on of the front cross members would cut our oil pan in half.

Looking in the engine bay of the NC, to me the spacing looks like it would work from the top. I guess you could premix to get around that problem, but still its going to be a bitch of a swap.

 

putting the renesis in a miata, i guess it would become a RX-5? would probably yield better mpg due to lighter weight. i think it would be sick. Mazda would have their own version of the Elise.

 

They should make a limited edition MX-5R, like 500 or so, maybe at the end of the production run of this model. That would be kickass

 

I've read a lot about miata's with rotaries and i remember reading in some magazine that they dont do it for cost related issues. Because if a miata would get a rotary engine, then that would mean that the cost of the miata would bump up and miata's are known for their great performance for a very reasonable price. And it said that if they get a rotary, another few thousand dollars would be added to the cost and blah blah blah.

Also, and us RX owners wouldnt feel that special anymore cause we're not the only ones with rotaries =X (haha, just kidding)

 

wouldnt it have to be a RX something? because RX stands for rotary expierement.....i like the sound of rx-5r. that would be killer

 

I keep hoping they will do a hardtop rotary Miata and make that the new RX-7 (or RX-9?). Only problem is, I think a lot of RX-7 guys (and other car enthusiasts) would snicker because hey, it's just a Miata hurrrr. Never mind that it's an awesome platform, and the power to weight ratio would match the FD (N/A renesis) or exceed it (turbo renesis). I bet you could sell a N/A version for the same price as the RX-8...which might be why they aren't doing it. Two similar cars at the same price point--it probably makes more sense to just work on a turbo'd Mazdaspeed RX-8.

 

The rotary engine would put an inexpensive, meant to be fun sports car into the same class as the Lotus Elan, BMW Z4 class - expensive to buy and maintain as well as un-foreseen reliability issues.

Also, it appears to be easier and cheaper to FI a piston engine than a rotary one.

 

So why is the rotary more expensive than piston engines? I understand the renesis is assembled by hand, but is that really necessary? Is there a reason they can't pump out rotaries on an automated assembly line? You would think that the same arguments made for reliability, such as fewer moving parts, would also make it easier to mass produce.

 

It is necessary. The answer as to why what you ask cannot happen is rather obvious. Is there a mass amount of people wanting a rotary in their car? I'll let someone else take it from here. I'll just say two words. BANDWAGON JUMPERS. Imagine what SONY would have been faced with if no one grasped the concept of a cd player., or a VCR.

 

Viking is correct. As much as most enthusiast on here love the rotary most folks don't grasp it or care to learn about it. Sales would suffer.

Take Sony and SACD for instance. Better format but most folks won't care. Cd is good enough for them.

 

i think its more of the marketing issue.
the original mx5 was a 1.6 litre piston engine 4 banger, and was regarded as one of the best handling car in its class. putting a rotary in it will involve change of name to ...... rx5? there is already a rx5 in the mazda's range (not in production atm). i quite like the new mx5, i think itd be perfect for a daily :D

having said that, i'd love to see a factory fitted rotary spec mx5 :D

 

The fact that few people would even consider transporting a rotary into an MX-5 (let alone any other cars) shows the lack of confidence and interest in it.

 

there seems to be more people trying to transplant LS1 into miatas

 

And RX7s!

 

The RX-8 isn't as expensive as those cars, and it's a 4-door car. Stick the renesis in a Miata (I assume the actual platform is cheaper to build), and you could probably sell it for a little less than an RX-8. This is assuming a N/A renesis of course.

But the real question is, which would be a better Mazdaspeed miata: a Renesis powered model, or a turbo'd version of the new NC motor. 170 base HP + a turbo could reach 238 HP I'd bet, with better gas mileage. On the other hand, maintenance/durability isn't bad for N/A rotaries, and you'd have slightly better weight and balance. But then again, the development costs would surely be higher to plug in a renesis, versus slapping on a turbo.

A turbo'd rotary Miata though...that would be a hell of a car, but there's probably not much of a market for a Miata in that price range. I don't think it would be up to Lotus or BMW prices, but maybe S2000 prices. Which is why they shouldn't sell it as a Miata at all--give it a hardtop and some cosmetic enhancements and sell it as a RX-7. :D

That's assuming Mazda can finally get their **** together with turbo'd rotaries. I know the factory versions have had problems, but is that just sloppy engineering, or are all rotaries just inherently short-lived when turbo'd? How do the FD's hold up with better cooling and single turbo setups, in terms of reliability?

 

Turbo / SC rotary's can be just as reliable as a NA if cooled properly and the turbo's aren't crap.

The 2nd gen turbo's were fine in terms of reliabilty but sucked from a performance standpoint. The 3rd gen's turbo's had crappy cooling and spun at ungodly high RPM's, therefore, were not reliable.

the newer generations of turbo's and s/c are much better in terms of flow and durability, and if cooled properly, would live long happy lives.