learned something new

On 2010-05-29, Chris D'Agnolo > wrote:

> really! The output shaft, eh?

Yup. The crankshaft of a Wankel is more-or-less in the center of the
engine. The crankshaft of a V-whatever or a vertical inline is at the
bottom. The crakshaft of a boxer is in the center, but a boxer isn't
very tall.

--
Grant

Chris D'Agnolo wrote:
>
> really! The output shaft, eh? If you know of any links to this project
> actually being done, post um up for us please. I always just figured
> that the compact size (of the rotary) would be simply wonderful under
> the hood of a Miata, interesting!
>
Allow me to offer a link to a not totally completed project :-)

http://www.timeattack.com.au/forum/viewtopic.php?p=1000

It's a pretty ambitious one I think going a bit beyond just a engine
swap. For a perhaps slightly smaller project simply google "Hansa 23R"
and you shall find the project of a German company which I think is
working towards selling a conversion kit. However this have been some
time coming since they completed the first conversion in December 2006.

Regards
Bruno


PS. Hi Chris :-)

On 2010-05-29 10:11:56 -0400, Grant Edwards > said:

> Yup. The crankshaft of a Wankel is more-or-less in the center of the
> engine. The crankshaft of a V-whatever or a vertical inline is at the
> bottom. The crakshaft of a boxer is in the center, but a boxer isn't
> very tall.

interesting. How does it work on the RX? A slope from the engine down
to the diff? An oddd tranny config.

In article >, Chris D'Agnolo
> wrote:

> "Lanny Chambers" > wrote in message
> ...
> > In article >,
> > "Chris D'Agnolo" > wrote:
> >
> >> A tech I met at an AZ dealership had plans to do the swap into his NB
> >> (iirc)
> >> but I don't know if he ever followed thru.
> >
> > A few such conversions have been done, but the height of the rotary's
> > output shaft is a formidable challenge. A V-8 is probably easier.
> >
> > --
> > Lanny Chambers
> > St. Louis, MO
> > '94C
>
> really! The output shaft, eh? If you know of any links to this project
> actually being done, post um up for us please. I always just figured that
> the compact size (of the rotary) would be simply wonderful under the hood of
> a Miata, interesting!
>
> cd

Height of the output shaft is not really an issue.
Output shaft center is relative to the flywheel, and the flywheel
diameter on the 12A and 13B rotaries are very close to the same size as
the Miata. There is not a lot below the bottom of the flywheel on
either engine. Just checked a 13B that the younger son has rebuilt to
go into a project RX7, and the flywheel is about even or slightly below
the bottom of the block. Not sure how far the oil pan drops below the
bottom of the flywheel on the two engines - you may lose some ground
clearance to the oil pan.
I think you have to look at it the other way.
In a piston engine, most of the mass and weight are above the
crankshaft.
In a rotary, the mass and weight are pretty much centered on the drive
shaft which should lower the overall weight centerline, and increase
handling.
Engine mounts would definitely need work. My one son has gotten pretty
hard core rotary and has wanted to put a 12A in a Miata. I looked in
the engine compartments of a first generation RX7, and the NA Miata,
and it is pretty close. Should fit without any extreme measures, and
the bell housing/tranny are nearly identical. Depending on the choice
of tranny, the shift turret may be in a different place. Early RX7s
were forward (or maybe that is behind) of where the later, and Miata
turret is located. Apparently there are fixes for that out there from
others converting early 1st gen RX7s to the 13B engine with matching
tranny.
Best place to find out about it is the RX7 forums.
http://www.rx7club.com/forum/
Found this-
http://www.rx7club.com/forum/showthr...ight=miata+rot
ary
and this thread
http://www.rx7club.com/forum/showthr...ight=miata+rot
ary
That may get you started.
From a quick scan, how to deal with the front sub frame, and steering
rack are the main issues.
Next is choosing what to do for the rest of the drive train. The
questions are how much extra power and torque the Miata rear and drive
shafts can take.

--
-------
Stephen Toth
white '93 220k mi. now rolled and dead
'06 Galaxy Grey GT 6AT

"Grant Edwards" > wrote in message
...
> On 2010-05-29, Chris D'Agnolo > wrote:
>
>> really! The output shaft, eh?
>
> Yup. The crankshaft of a Wankel is more-or-less in the center of the
> engine. The crankshaft of a V-whatever or a vertical inline is at the
> bottom. The crakshaft of a boxer is in the center, but a boxer isn't
> very tall.
>
> --
> Grant

That makes sense, never thought about it like that.

cd
99BBB

On 5/20/2010 1:43 AM, Chris D'Agnolo wrote:
>
> "pws" > wrote in message >
>> I can see some people preferring the older style, (not me!), but I
>> could not believe that Mazda would have done this for such a small
>> market.
>>
>> Unless some engineer figured out at the last minute what could be fit
>> where, and within budget............Anyone know for sure why this
>> hardtop exists at all?
>>
>> Pat
>
> I would have to call it an anomaly. One of those goof ups big companies
> sometimes make. I can't imagine how few were sold or how much $ was
> spent in the R&D and build process.
>
> Chris
> 99BBB
>
I really think that the detachable NC hard top is a concession to the
racing fraternity. It allows the rules to permit a lighter racing
version as a "stock production" version.

"Chuck" > wrote in message > I really think that the
detachable NC hard top is a concession to the
> racing fraternity. It allows the rules to permit a lighter racing version
> as a "stock production" version.
>
>

That's a possibility I guess. Hey Pat, check out the thread Bruno listed,
that NC has a hard top on it. I'll have to take a look at Stephen's links.
Obviously their are people out there working on this but Mazda could do it
in a heartbeat!

Here's my suggestion to Mazda; New Mazdaspeed Miata with the 13b rotary in
it and if MX-5 bothers you call it an RX-5 Mazdaspeed ;-) This could be a
wonderful performance car with the 'right' price since Mazda would be mostly
digging into their parts bin!

Come on Mazda!

We can try!
Chris
99BBB

Chris D'Agnolo wrote:
>
> "Chuck" > wrote in message > I really think that the
> detachable NC hard top is a concession to the
>> racing fraternity. It allows the rules to permit a lighter racing
>> version as a "stock production" version.
>>
>>
>
> That's a possibility I guess. Hey Pat, check out the thread Bruno
> listed, that NC has a hard top on it. I'll have to take a look at
> Stephen's links. Obviously their are people out there working on this
> but Mazda could do it in a heartbeat!
>
> Here's my suggestion to Mazda; New Mazdaspeed Miata with the 13b rotary
> in it and if MX-5 bothers you call it an RX-5 Mazdaspeed ;-) This could
> be a wonderful performance car with the 'right' price since Mazda would
> be mostly digging into their parts bin!
>
> Come on Mazda!
>
> We can try!
> Chris
> 99BBB

That looks cool! I will have to check it out later in more detail when I
have some time. That Mazdaspeed front bumper looks very cool.

Pat

"Bruno, Copenhagen - Denmark" > wrote in
message ...
> Chris D'Agnolo wrote:
>>
>> really! The output shaft, eh? If you know of any links to this project
>> actually being done, post um up for us please. I always just figured that
>> the compact size (of the rotary) would be simply wonderful under the hood
>> of a Miata, interesting!
>>
> Allow me to offer a link to a not totally completed project :-)
>
> http://www.timeattack.com.au/forum/viewtopic.php?p=1000
>
> It's a pretty ambitious one I think going a bit beyond just a engine swap.
> For a perhaps slightly smaller project simply google "Hansa 23R" and you
> shall find the project of a German company which I think is working
> towards selling a conversion kit. However this have been some time coming
> since they completed the first conversion in December 2006.
>
> Regards
> Bruno
>
>
> PS. Hi Chris :-)

Bruno, LIFE IS TOO SHORT! Either that or I'm simply too slow at everything I
want to do! I've spent hours following the 13B into NC build! I haven't
caught up yet but I'm still in there. This deserves it's own post my friend!
Thanks for linking it, this guy is amazingly talented and has spent
unbelievable hours documenting everything! I love this guy!

Thanks again!
Chris
99BBB

"pws" > wrote in message . That Mazdaspeed front
bumper looks very cool.
>
> Pat

Fixes that nasty GRIN everybody hates!

Chris
99BBB