[CometCyclone]

I used to see quite a few RX-7's on the road back in the 80's, and the first generation had rotary engines, but I'm not aware of any other cars that had them....

I've heard that they have less vibration than a piston engine, but they suffer from incomplete combustion when running.

Anyone ever own one or know anything else about them?

[T-bucket23]

They ran very smooth, unfortunately like everything else, oddball stuff just doesnt seem to catch on.

[Joe G]

My best friend is a Mazda rotary nut and currently drives an RX-8. As I understand it, the drawbacks of a Mazda rotary engine as compared to modern piston engines of similar output are:
1. Bad fuel economy (his stock RX-8 gets about 15-18 MPG).
2. Minimal low-end torque.
3. Poor longevity.

The advantages are:
1. Light weight.
2. Far fewer moving parts.
3. Minimal vibration.
4. ?????

[327NUT]

I had an older Mazda truck with the rotary...and yes it got lousy gas mileage. It did haul butt though ......probably why the chit mileage.

[DoubleVision]

Maybe this will explain it all:
http://www.youtube.com/watch?v=zxsY4lEGRBI

[SDLuck]

My 1984 GSL SE RX7 got in the low 20,the 1985 had a taller overdrive and got a little better.Don't know about the RX8.The 1995 turbo model stock was 250 hp from 80 ci.

[sweet willy]

What I remember is that there was a cooling problem with the tips of the rotors. They would get overheated and prematurely wear and that caused the loss of compression. FYI: Suzuki made a motorcycle with a Rotary engine. The funny part was since a rotary engine is always on a compression stroke you couldn't kick start the thing even though it had a kick starter. I weighed about 175 lbs. back then and I couldn't get the kick starter to even move.

[sbchevfreak]

Another benefit of the rotary design is that you are not changing reciprocating motion to rotational motion. Any time you have a change of direction, you lose power. The rotary uses a rotational impetus to produce a rotational output.

With newer tech, and advanced materials, new generations of rotary engines should easily overcome the problems of the early designs.

[malc]

RO80, history.
"Second hand Ro80s were virtually worthless in the 1970s due to the well-publicised engine problems, and a common "cure" for an ailing rotary engine was to simply swap it for a Ford V4 "Essex" engine (as found in Mk1 Transits) since it was one of the few engines compact enough to fit in the Ro80's engine bay.Thus in an ironic twist, one of the smoothest engines in the world was replaced by one of the roughest."

Sister in law had a Mazda RX-8 rotory, came with a driving course included.
Biggest drawback was oil consumption, sold the car having had it only one year.

[Shelby1]

Over heating and distortion of engine case led to wipe out of the rotor tips and resulting in loss of compression....rev like there was no tomorrow but that was about it.
by the way the owner of the patient on the rotary engine was Volkswagen AG...which tru their research decided it was not a viable power plant...which kind of tells you something....The Germans did not think that it was worth the effort to continue with ......soooo they licensed it to the Japanese for manufacture
Kenny

[Dave57210]

I never have owned one, only ever drove one once or twice. As has been noted, low-end torque was very precisely defined as being Pi squared times 1/3 of the cube root of zero, but they could scream out the RPM's and were silky-smooth.

If memory serves, the original Felix Wankel engine design was initially developed by a German company - (NSU????) and then licensed to Mazda

GM decided to use it, too and developed a few cars around it - I think the Monza was slated to get it. GM also agreed to sell rotaries to AMC and the AMC Pacer was developed specifically around that engine.

GM, being GM, declined to buy the rights from Mazda (which would have allowed them access to Mazda's development and refinement of it) and chose to get a license from (NSU???)

After GM spent "a zillion dollars" on trying to get it work at least as well as the Mazda version, they ashcanned the project. The Monza then got various 4's V6's and V8's and the Pacer wound up with a 6 that never quite fit in the engine room properly.

I seem to recall that way back (early 70's?) Car & Driver raced a very fast Mazda rotary in the showroom stock sports car series with great success - so much so that the engine got effectively legislated out of competition in that series.

[matts37chev]

Originally Posted by DoubleVision

Maybe this will explain it all:
http://www.youtube.com/watch?v=zxsY4lEGRBI

i had asked about rx-7s a while back because my son wants one
so this thread caught my attention
that u-tube video is great i am laughing out loud, and my wife is wondering what the heck are you watching
it will be showed to the boy

[oldschool hero]

If I recall these were Wrankle engines,named after the engineer who devolped it. And the big problem was loss of compression due to the tips of the rotors failing.

[Dragonoake]

Originally Posted by Dave57210

I seem to recall that way back (early 70's?) Car & Driver raced a very fast Mazda rotary in the showroom stock sports car series with great success - so much so that the engine got effectively legislated out of competition in that series.

A little more info on that: http://www.racingbeat.com/manuals/RBHistory.pdf

[Everett II]

I bought a brand new '80 RX-7 GS with a 5 speed in November of '79. I kept that car for 10 years and well over a 100,000 miles. Never had an issue with the 100 cubic inch rotary. Not much low end torque, but you could easily spin it past 7 grand. Mileage was fair, around 20 but definitely a fun ride. In about '85 I installed a Miarah wide body kit, Racing Beat exhaust and air filter. Unique sound it made when WFO.

The only problem I had, which I got repaired under warranty was a cracked second gear synchronizer, which I did racing in Orlando. (Told the dealer my girlfriend did it!!!). I traded it in 1990 for a Jeep. Wish I still had that RX-7, it was actually the most reliable auto I have owned.